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SUGT1

Protein SGT1 homolog · UniProt Q9Y2Z0

Length
365 aa
Mass
41.0 kDa
Annotated
2026-04-28
100 papers in source corpus 39 papers cited in narrative 37 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

SUGT1 (SGT1) is a conserved co-chaperone that bridges HSP90 and HSC70 chaperone systems to diverse client proteins, orchestrating the assembly and stabilization of multiprotein complexes required for kinetochore function, SCF ubiquitin ligase activity, and innate immune receptor (NLR) signaling. Through its CS domain, SUGT1 binds the HSP90 N-terminal domain at a site distinct from the p23 co-chaperone, while its TPR domain engages Skp1 and its SGS domain interacts with HSC70, enabling SUGT1 to coordinate chaperone-assisted folding with ubiquitin-proteasome-mediated substrate turnover (PMID:14761955, PMID:18818696, PMID:18065690, PMID:10445024). In mitosis, Plk1 phosphorylates SUGT1 at Ser331 to enhance HSP90–SUGT1 association with the MIS12 complex and promote NDC80 recruitment for stable kinetochore–microtubule attachment, while PHLPP1-mediated dephosphorylation of SUGT1 prevents RNF41-dependent ubiquitination and degradation, coupling SUGT1 protein stability to kinetochore integrity (PMID:22869522, PMID:28696259, PMID:15133482). In innate immunity, SUGT1–HSP90 stabilizes NLR proteins including NLRP3, IPAF, Nod1, and Nod2, and MAPK-mediated phosphorylation of SUGT1 regulates its nucleocytoplasmic partitioning and potentiates SCF-dependent degradation of immune suppressors to activate defense responses (PMID:17435760, PMID:17420470, PMID:32976518, PMID:39066482).

Mechanistic history

Synthesis pass · year-by-year structured walk · 16 steps
  1. 1999 High

    Identification of SGT1 as a Skp1-interacting protein established it as a component of the SCF ubiquitin ligase and a factor required for yeast kinetochore (CBF3) assembly, revealing that a single protein could link ubiquitination to chromosome segregation.

    Evidence Dosage suppressor screen, reciprocal co-IP, in vitro ubiquitination, and cross-species complementation in S. cerevisiae and human cells

    PMID:10445024

    Open questions at the time
    • Mechanism by which SGT1 activates Ctf13 was unclear
    • Whether SGT1 functions as a chaperone rather than a stoichiometric SCF subunit was not resolved
    • No structural information on the SGT1-Skp1 interface
  2. 2002 High

    Discovery that plant SGT1 interacts with RAR1 and SCF/COP9 signalosome components during pathogen resistance generalized SGT1 function beyond cell division to innate immunity and established its role in NLR-mediated defense signaling.

    Evidence Yeast two-hybrid, co-IP, and virus-induced gene silencing in Arabidopsis and tobacco

    PMID:11847307

    Open questions at the time
    • Whether SGT1 acted as a chaperone cofactor or as a signaling adaptor was unknown
    • Direct interaction with NLR receptors was not shown
  3. 2003 High

    Structural determination of the SGT1 CS domain and its HSP90-binding mode showed that SGT1 is an HSP90 co-chaperone using a p23-like fold but with a distinct, ATP-independent binding mechanism, redefining SGT1 as a chaperone pathway component rather than a simple scaffold.

    Evidence NMR structure of human SGT1 CS domain, binding assays with domain deletions, and pharmacological/genetic demonstration that HSP90 is essential for R-protein resistance

    PMID:14504384 PMID:14583611 PMID:14761955

    Open questions at the time
    • Atomic details of the HSP90-CS interface were not resolved
    • Role of the TPR and SGS domains remained uncharacterized
  4. 2004 High

    RNAi depletion of human SGT1 demonstrated its essential role in kinetochore assembly in mammalian cells — preventing localization of Hec1, CENP-E, CENP-F, and CENP-I — directly translating the yeast kinetochore phenotype to human mitosis and revealing SGT1 acts upstream of outer kinetochore assembly.

    Evidence siRNA knockdown in HeLa cells with immunofluorescence for kinetochore protein localization and spindle checkpoint assay

    PMID:15133482

    Open questions at the time
    • Which kinetochore subcomplexes are direct SGT1 clients was unknown
    • Whether HSP90 is required alongside SGT1 in mammalian kinetochore assembly was not tested
  5. 2004 High

    Demonstration that HSP90 binding to yeast Sgt1 stimulates the Sgt1-Skp1 interaction and promotes stepwise CBF3 assembly established a chaperone-driven assembly pathway rather than passive scaffolding.

    Evidence Co-IP, genetic analysis of sgt1 mutants, and in vitro binding reconstitution in S. cerevisiae

    PMID:15340069

    Open questions at the time
    • Whether HSP90 ATPase activity is required for the stimulatory effect was not determined
    • No reconstitution with purified components
  6. 2007 High

    Multiple studies converged to show that SGT1–HSP90 directly stabilizes mammalian NLR proteins (NLRP3, IPAF, Nod1, Nod2) and that SGT1 depletion abrogates inflammasome and NF-κB signaling, establishing the SGT1–HSP90 axis as a general NLR maturation/activation platform in innate immunity.

    Evidence Co-IP of SGT1 with multiple NLRs, siRNA knockdown ablating Nod1/Nod2/NLRP3 responses, HSP90 inhibition in mouse inflammation models

    PMID:17420470 PMID:17435760

    Open questions at the time
    • Whether SGT1 acts on NLR folding, assembly, or conformational activation was not distinguished
    • Stoichiometry of SGT1-NLR complexes was unknown
  7. 2007 High

    Identification of HSC70 as a second chaperone partner of SGT1 (via the SGS domain) and demonstration that this interaction controls SGT1 nuclear accumulation expanded the co-chaperone network beyond HSP90 and revealed a role for SGT1 in nucleocytoplasmic partitioning.

    Evidence AP-MS, reciprocal co-IP, domain deletion, and confocal microscopy in Arabidopsis

    PMID:18065690

    Open questions at the time
    • Whether HSC70 and HSP90 form a ternary complex with SGT1 or act sequentially was unclear
    • Mammalian HSC70-SGT1 interaction was not validated
  8. 2007 High

    NMR mapping of the CS domain showed RAR1-CHORD II and HSP90 bind opposite CS faces, and MAPK-mediated phosphorylation of SGT1 was shown to regulate its nuclear accumulation and NLR resistance, establishing phosphorylation as a regulatory input into the SGT1 chaperone cycle.

    Evidence NMR surface mapping, random mutagenesis, in planta functional assays; mass spectrometry identification of MAPK phospho-site with phospho-mutant analysis

    PMID:18032631 PMID:23731343

    Open questions at the time
    • Identity of the MAPK phosphorylation site in mammalian SGT1 was not determined
    • Whether phosphorylation directly affects HSP90 or client binding was not resolved
  9. 2008 High

    Crystal structures of the Hsp90–Sgt1 CS-domain complex and characterization of Sgt1 dimerization via the TPR domain provided the first atomic framework for how SGT1 bridges HSP90 to SCF substrates, with dimerization shown to be essential for Skp1 binding and kinetochore function.

    Evidence X-ray crystallography of Hsp90-CS complex, NMR of HSP90 binding surface, analytical ultracentrifugation, compensatory mutagenesis validated in plants and yeast

    PMID:18818696 PMID:18833289 PMID:19073600

    Open questions at the time
    • No structure of full-length SGT1 or a complete SGT1-Skp1-HSP90 ternary complex
    • How dimerization is regulated in vivo was unknown
  10. 2008 High

    Drosophila Sgt1 was shown to stabilize Polo kinase and be required for centrosome maturation, identifying a kinase as a direct SGT1–HSP90 client and broadening SGT1's mitotic roles beyond kinetochores.

    Evidence Genetic mutant analysis, immunofluorescence, rescue by Polo overexpression in Drosophila

    PMID:19131964

    Open questions at the time
    • Whether SGT1 directly chaperones Polo or acts indirectly was not biochemically resolved
    • Mammalian Plk1 as a client was not tested
  11. 2009 High

    CK2 phosphorylation of Sgt1 at Ser361 was shown to inhibit dimerization, providing the first kinase-mediated regulatory switch for SGT1 oligomeric state and thus its capacity to bind Skp1.

    Evidence In vitro kinase assay, phospho-site mutagenesis, dimerization assay in yeast

    PMID:19398558

    Open questions at the time
    • Physiological conditions triggering CK2-dependent SGT1 monomerization were not identified
    • Whether CK2 regulation is conserved in mammals was not tested
  12. 2010 High

    Crystal structure of the Hsp90–CS–CHORD ternary complex and identification of the Mis12 complex as an HSP90–SGT1 client at kinetochores defined the architectural basis for NLR receptor recruitment and directly linked SGT1 to outer kinetochore stabilization in human cells.

    Evidence X-ray crystallography with mutagenesis; co-IP of HSP90-SGT1-Mis12, RNAi phenotyping of chromosome alignment

    PMID:20404110 PMID:20670895

    Open questions at the time
    • Whether SGT1 acts catalytically or stoichiometrically at kinetochores was unresolved
    • How SGT1 is recruited to kinetochores in the first place was not known
  13. 2012 High

    Plk1-mediated phosphorylation of SGT1 at Ser331 at kinetochores was shown to enhance HSP90–SGT1 interaction with MIS12 and promote NDC80 recruitment, establishing a direct kinase-regulated mechanism linking SGT1 co-chaperone activity to microtubule attachment competence during prometaphase.

    Evidence In vitro kinase assay, phospho-site mutagenesis, co-IP, kinetochore localization and chromosome alignment in human cells

    PMID:22869522

    Open questions at the time
    • Whether Plk1 phosphorylation affects SGT1 dimerization or HSP90 ATPase cycle was not tested
    • Temporal coordination with CK2 phosphorylation was unknown
  14. 2017 High

    Structural determination of the yeast Sgt1 TPR–Skp1 complex, characterization of SGT1–HSP90 in CENP-A deposition, and discovery that PHLPP1 dephosphorylation protects SGT1 from RNF41-mediated ubiquitination collectively revealed how SGT1 protein stability and client engagement are coupled through phosphorylation-dependent degradation control.

    Evidence X-ray crystallography of TPR-Skp1, siRNA/ChIP for CENP-A deposition, in vitro phosphatase and ubiquitination assays with mutagenesis

    PMID:28139700 PMID:28696259 PMID:28816574

    Open questions at the time
    • Full-length SGT1 structure in complex with HSP90 and a client remains unavailable
    • Whether PHLPP1-SGT1 regulation operates at kinetochores specifically or globally was unclear
    • CENP-A deposition mechanism confirmed by single lab only
  15. 2020 Medium

    Diverse new SGT1 client relationships emerged: SUGT1 stabilizes microtubule plus-ends via EB1/acetylation to promote HIV-1 trafficking; necdin recruits SGT1–HSP90 to stabilize the circadian clock protein BMAL1; and the lncRNA SAM stabilizes Sugt1 protein to maintain kinetochore integrity during myoblast proliferation, expanding the functional scope of SGT1 beyond classical chaperone clients.

    Evidence siRNA with live-cell imaging and HIV infectivity; Y2H/co-IP with circadian reporter; RNA-protein pulldown with mouse knockout and kinetochore assays

    PMID:32483152 PMID:32514048 PMID:32667666

    Open questions at the time
    • Microtubule plus-end stabilization mechanism is from a single lab and lacks reconstitution
    • BMAL1 stabilization pathway not validated in vivo in mammals
    • SAM lncRNA interaction domain on SGT1 not mapped
  16. 2024 Medium

    SGT1 was shown to promote SCF-dependent degradation of the immune suppressor NSL1 downstream of MAPK phosphorylation, demonstrating that SGT1 controls NLR activation not only through receptor stabilization but also through targeted elimination of negative regulators.

    Evidence TurboID proximity labeling, co-IP, degradation assays, phospho-site mutagenesis, NLR resistance assays in plants

    PMID:39066482

    Open questions at the time
    • Whether analogous negative-regulator degradation pathways exist in mammalian NLR signaling is untested
    • Single-lab finding awaiting independent replication

Open questions

Synthesis pass · forward-looking unresolved questions
  • Key open questions include: the structure of a full-length SGT1 in complex with HSP90 and a bona fide client; how SGT1 selects among its diverse clients (kinetochore, NLR, SCF substrates); the mechanistic basis for SGT1's microtubule-stabilizing activity; and whether the multiple phosphorylation inputs (Plk1, CK2, MAPK, PHLPP1/RNF41) are integrated in a coherent regulatory circuit during mitosis.
  • No full-length SGT1-HSP90-client ternary structure
  • Client selectivity mechanism unknown
  • Integration of phosphorylation inputs not systematically studied

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0044183 protein folding chaperone 6 GO:0060090 molecular adaptor activity 5 GO:0098772 molecular function regulator activity 4
Localization
GO:0005694 chromosome 4 GO:0005634 nucleus 3 GO:0005829 cytosol 2
Pathway
R-HSA-1640170 Cell Cycle 8 R-HSA-168256 Immune System 7 R-HSA-392499 Metabolism of proteins 7
Partners
HSP90MIS12PHLPP1PLK1RAR1RNF41S100A6SKP1
Complex memberships
CBF3 kinetochore complexHSP90-SGT1 co-chaperone complexSCF ubiquitin ligase complex

Evidence

Reading pass · 37 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
1999 SGT1 (yeast ortholog) physically associates with Skp1p in vivo and in vitro, is a novel subunit of the SCF (Skp1p/Cdc53p/F-box protein) ubiquitin ligase complex, and is required for assembling the yeast kinetochore complex CBF3 via activation of Ctf13p. Human SGT1 rescues the yeast null mutation, demonstrating functional conservation. Dosage suppressor screen, in vivo and in vitro co-immunoprecipitation/pulldown, conditional mutant phenotypic analysis, in vitro ubiquitination assay, cross-species complementation Molecular cell High 10445024
2002 Plant SGT1 orthologs interact with RAR1 and associate with SKP1 and CUL1 (SCF ubiquitin ligase subunits) as well as two COP9 signalosome components, linking disease resistance signaling to ubiquitination machinery. Yeast two-hybrid, co-immunoprecipitation, virus-induced gene silencing (VIGS) functional assay Science High 11847307
2003 Human SGT1 binds HSP90 through its CS (CHORD-SGT1) domain, not through its tetratricopeptide repeat (TPR) domain, and this interaction does not require ATP (unlike p23-HSP90 binding). The CS domain adopts a beta-sandwich fold structurally similar to p23 but functionally distinct. NMR spectroscopy, 3D structure determination, binding assays with domain deletions The Journal of biological chemistry High 14761955
2003 HSP90 interacts with SGT1 (via SGT1's TPR motif and p23-like domain) and with RAR1, forming a chaperone complex that is essential for R protein (RPS2, N)-mediated plant disease resistance; HSP90 inhibition abrogates resistance responses. Yeast two-hybrid, co-immunoprecipitation, pharmacological inhibition (geldanamycin), loss-of-function genetics Proceedings of the National Academy of Sciences of the United States of America High 14504384 14583611
2004 Human Sgt1 depletion by RNAi in HeLa cells causes defective kinetochore assembly, preventing localization of Hec1, CENP-E, CENP-F, and CENP-I (but not CENP-C) to mitotic kinetochores, weakening the spindle checkpoint and causing chromosome alignment defects. RNA interference, immunofluorescence microscopy, mitotic checkpoint assay EMBO reports High 15133482
2004 In budding yeast, Sgt1 interacts with Hsp90 (Hsc82) via its N-terminal TPR-containing region; Hsp90 binding to Sgt1 stimulates Sgt1-Skp1 interaction, and together Sgt1 and Hsp90 promote Skp1-Ctf13 binding to assemble the CBF3 kinetochore complex. Co-immunoprecipitation, genetic analysis of sgt1 mutants, in vitro binding assays Molecular and cellular biology High 15340069
2007 Many mammalian NLR proteins (NALP3, IPAF, Nod2) interact with SGT1 and HSP90; siRNA knockdown of SGT1 abrogates inflammasome activity, and HSP90 inhibition blocks Nod2-mediated NF-κB activation and NALP3-mediated inflammation in mice. Co-immunoprecipitation, siRNA knockdown, in vivo mouse inflammation model, pharmacological inhibition Nature immunology High 17435760
2007 SGT1 is required for Nod1 activation: siRNA depletion of SGT1 prevents multiple Nod1-dependent cellular responses without affecting Nod1 protein stability; HSP90 depletion destabilizes Nod1 protein. Rar1 ortholog Chp1 is not required for Nod1 function. siRNA knockdown, functional cellular assays, immunoblot Proceedings of the National Academy of Sciences of the United States of America High 17420470
2007 Arabidopsis SGT1a and SGT1b associate with HSC70 chaperones in the cytosol and nucleus in vivo; the C-terminal SGS domain of SGT1b is required for HSC70 interaction and for nuclear accumulation of SGT1b. SGT1 functions as an HSC70 cofactor. Affinity purification-mass spectrometry, co-immunoprecipitation, subcellular fractionation, domain-deletion analysis, confocal microscopy The Plant cell High 18065690
2007 NMR-based mapping of the plant SGT1 CS domain shows that RAR1 CHORD II and the HSP90 N-terminal domain interact on opposite faces of the CS domain. Mutagenesis confirms that the SGT1-HSP90 interaction is required for accumulation of the R protein Rx. RAR1 may enhance the SGT1-HSP90 interaction by promoting ternary complex formation. NMR surface mapping, random mutagenesis, biochemical reconstitution, in planta functional assay The Plant cell High 18032631
2007 Tobacco SGT1 undergoes MAPK (SIPK)-mediated phosphorylation at a canonical MAPK motif; phospho-mimic and phospho-null mutations at this site alter SGT1 nuclear accumulation and impair N-mediated TMV resistance. SGT1 controls nucleocytoplasmic partitioning of the N resistance protein. Mass spectrometry, site-directed mutagenesis, confocal microscopy, pathogen resistance assay The New phytologist High 23731343
2008 Crystal structure of the core Hsp90-Sgt1 complex reveals a distinct interaction site on the Hsp90 N-terminal domain. Interface mutations in Sgt1 that abrogate Hsp90 binding disrupt Sgt1-dependent functions in plants and yeast. Sgt1 bridges the Hsp90 chaperone system to SCF ubiquitin ligase complexes. X-ray crystallography, site-directed mutagenesis, in vivo functional assays in plants and yeast The EMBO journal High 18818696
2008 NMR and mutational analysis of HSP90 define the binding surface for the SGT1 CS domain. Full-length SGT1 can displace p23 from HSP90, yet CS and p23 bind non-competitively to different HSP90 regions. RAR1 partly overlaps the CS-domain binding site on HSP90. A compensatory mutant pair between SGT1 and HSP90 that restores Rx-mediated virus resistance was identified. NMR spectroscopy, site-directed mutagenesis, in vivo virus resistance assay EMBO reports High 18833289
2008 Drosophila Sgt1 stabilizes Polo kinase protein levels; loss of Sgt1 reduces total Polo protein, prevents centrosome maturation and pericentriolar material recruitment, and causes highly abnormal mitotic spindles. Overexpression of Polo substantially rescues the sgt1 centrosome defects. Drosophila genetic mutant analysis, immunofluorescence, rescue by Polo overexpression The EMBO journal High 19131964
2008 Yeast Sgt1 forms homodimers via its N-terminal Skp1-binding domain (aa 1–211); dimerization is required for Sgt1-Skp1 binding and kinetochore assembly. Restoring dimerization of a dimerization-deficient mutant via a heterologous dimerization domain rescues kinetochore function. In vitro and in vivo co-immunoprecipitation, analytical ultracentrifugation, domain deletion, functional complementation The Journal of biological chemistry High 19073600
2009 Protein kinase CK2 phosphorylates yeast Sgt1 at Ser361, and this phosphorylation inhibits Sgt1 dimerization. In vitro kinase assay, phospho-site mutagenesis, dimerization assay The Journal of biological chemistry High 19398558
2010 Crystal structure of Hsp90-CS-CHORD ternary complex defines the architecture for recruiting NLR receptors; mutational and biochemical analyses show that CHORD and CS domains independently bind Hsp90 and can coexist in complexes, controlling the ATPase-dependent conformational cycle of the chaperone. X-ray crystallography, mutagenesis, biochemical binding assays Molecular cell High 20670895
2010 Human Hsp90-Sgt1 interacts with the Mis12 kinetochore complex; inhibition of Hsp90 or Sgt1 destabilizes the Mis12 complex and delays chromosome alignment due to inefficient microtubule-binding site formation. Coinhibition of Sgt1 and Skp1 increases Mis12 at kinetochores, suggesting competitive regulation. Co-immunoprecipitation, RNAi knockdown, chromosome alignment and kinetochore localization assays The Journal of cell biology High 20404110
2012 Plk1 phosphorylates Sgt1 at Ser331 at kinetochores during prometaphase; this phosphorylation enhances the association of the Hsp90-Sgt1 chaperone with the MIS12 complex to stabilize it at kinetochores and recruit the NDC80 complex, promoting stable microtubule attachment. Loss of this phosphorylation causes chromosome misalignment. In vitro kinase assay, phospho-site mutagenesis, co-immunoprecipitation, kinetochore localization assay, chromosome alignment analysis Molecular and cellular biology High 22869522
2012 In Drosophila neuroblasts, Sgt1 acts through an LKB1/AMPK pathway to establish apical cortical polarity at prophase; activated AMPKα rescues the sgt1 cortical polarity defect. Sgt1 and Hsp90 (Hsp83) act in the same pathway upstream of LKB1-AMPK. Drosophila genetic screen, double-mutant epistasis, rescue by activated AMPKα Developmental biology Medium 22248825
2012 Scrib (mammalian Scribble) associates with Sgt1 via its LRR domain; Sgt1 and HSP90 are required to maintain proper Scrib protein levels. Loss of Sgt1-HSP90 destabilizes Scrib and reduces the Scrib-βPix-PAK complex, blocking HGF-mediated epithelial morphogenesis. Co-immunoprecipitation, siRNA knockdown, 3D epithelial morphogenesis assay, immunoblot Journal of cell science Medium 22623728
2013 The Salmonella effector SspH2 interacts with SGT1 specifically through SGT1's NLR co-chaperone function (not its cell-cycle function); SspH2 ubiquitinates Nod1, and SGT1 interaction enhances SspH2 in vitro ubiquitination activity and protein stability. Catalytically active SspH2 can induce Nod1 activity in an agonist-independent manner. Co-immunoprecipitation, in vitro ubiquitination assay, siRNA knockdown, domain-specificity analysis PLoS pathogens High 23935490
2013 Human SGT1 regulates Akt signaling in gastric cancer cells by promoting beta-TrCP-mediated degradation of PHLPP1 (the Akt Ser473 phosphatase); SGT1 enhances the PHLPP1-beta-TrCP interaction, reducing PHLPP1 levels and increasing Akt Ser473 phosphorylation. siRNA knockdown, co-immunoprecipitation, immunoblot for phosphorylation status, colony formation assay Molecular biology reports Medium 23440515
2017 Crystal structure of the yeast Sgt1 TPR domain in complex with the Skp1 BTB/POZ domain at 2.8 Å reveals that Skp1 binds the concave surface of the Sgt1 TPR domain via conserved residues. Sgt1 dimerization in yeast occurs via a TPR insertion absent from monomeric human Sgt1. Skp1 binding is an essential function of Sgt1 in yeast. X-ray crystallography, mutagenesis, in vitro binding assay, yeast complementation Scientific reports High 28139700
2017 The SGT1-HSP90 complex is required for CENP-A deposition at centromeres; SGT1-HSP90 promotes recognition of CENP-A by COPS8 (part of the CUL4A-RBX1-COPS8 E3 ligase), enabling CENP-A K124 ubiquitylation required for centromeric CENP-A deposition. siRNA knockdown, co-immunoprecipitation, chromatin immunoprecipitation, ubiquitylation assay Cell cycle Medium 28816574
2017 PHLPP1 interacts with SGT1 and stabilizes it by dephosphorylating SGT1 at Ser-17, Ser-249, Ser-289, and Thr-233, preventing SGT1 association with the E3 ligase RNF41 and consequent ubiquitin-mediated SGT1 degradation. Loss of PHLPP1 causes SGT1 degradation and defective kinetochore assembly. Co-immunoprecipitation, in vitro dephosphorylation assay, ubiquitination assay, site-directed mutagenesis, kinetochore assembly assay The Journal of biological chemistry High 28696259
2020 The bacterial effector RipAC associates with SGT1, inhibits its interaction with MAP kinases, and prevents MAPK-mediated phosphorylation of a canonical MAPK motif in the C-terminal domain of SGT1. This phosphorylation is enhanced upon immune activation and contributes to NLR (RPS2)-mediated immunity. Co-immunoprecipitation, in vitro kinase assay, phospho-site mutagenesis, bacterial pathogen resistance assay PLoS pathogens High 32976518
2020 SUGT1 stabilizes microtubule plus-ends of host cells through modulation of microtubule acetylation and EB1 comet formation; this promotes HIV-1 retrograde trafficking and nuclear import of the viral genome, making SUGT1 a permissive factor for HIV-1 infection. siRNA knockdown, live-cell imaging, microtubule acetylation assay, EB1 comet analysis, HIV-1 infectivity assay Cell death and differentiation Medium 32514048
2020 Necdin recruits the SGT1-HSP90 chaperone machinery to stabilize BMAL1, a core circadian clock component; depletion of necdin or SGT1/HSP90 leads to BMAL1 degradation via the ubiquitin-proteasome system and disrupts circadian rhythms. Yeast two-hybrid, co-immunoprecipitation, siRNA knockdown, cycloheximide chase, circadian reporter assay Nucleic acids research Medium 32667666
2020 lncRNA SAM interacts with and stabilizes Sugt1 protein in proliferating myoblasts; loss of SAM or Sugt1 disrupts kinetochore assembly (mislocalization of Dsn1 and Hec1) and impairs myoblast proliferation and muscle regeneration. RNA-protein pulldown, co-immunoprecipitation, kinetochore localization assay, genetic deletion in mice Nature communications Medium 32483152
2023 Sugt1 promotes ubiquitination of p21 via the E3 ligase Trim21; loss of Sugt1 in muscle stem cells causes p21 accumulation, G2/M cell cycle arrest, and cellular senescence, impairing muscle regeneration. Co-immunoprecipitation, ubiquitination assay, cell cycle analysis, in vivo genetic deletion Life medicine Medium 39872547
2024 SGT1 interacts with NSL1 (a negative regulator of SA-mediated defense) and promotes SCF-dependent degradation of NSL1 to facilitate NLR immune activation; SIPK-mediated phosphorylation of SGT1 potentiates this NSL1 degradation. This SGT1-NSL1 module functions downstream of multiple NLRs. TurboID proximity labeling, co-immunoprecipitation, degradation assays, phospho-site mutagenesis, NLR resistance assay Molecular plant Medium 39066482
2003 Sgt1 interacts with S100A6 (calcyclin) and other S100 proteins (S100B, S100P) in a calcium-regulated manner; the S100A6-binding domain maps to the 71 C-terminal residues of Sgt1. S100A6 binding inhibits casein kinase II-mediated phosphorylation of this domain and does not interfere with Skp1-Sgt1 binding. Affinity chromatography, chemical cross-linking, co-immunoprecipitation from cell extract, in vitro kinase assay The Journal of biological chemistry Medium 12746458
2007 Sgt1 interacts with Hsp70 in addition to Hsp90; the C-terminal region of Sgt1 is required for both interactions. S100A6 overexpression decreases Hsp70 and Hsp90 binding to Sgt1 in a calcium-dependent manner. Co-immunoprecipitation, affinity chromatography, ELISA, deletion mutant analysis Biochemical and biophysical research communications Medium 17466273
2010 S100A6 in its Ca2+-bound form mediates nuclear translocation of Sgt1 upon heat shock; dephosphorylation of Sgt1 at Ser299 (and Ser249) promotes nuclear translocation, likely through disruption of the Sgt1-Hsp90 complex, while non-phosphorylatable Sgt1 mutants show enhanced S100A6 interaction and reduced Hsp90 binding. siRNA knockdown of S100A6, phospho-mutant transfection, subcellular fractionation, co-immunoprecipitation Amino acids / The international journal of biochemistry & cell biology Medium 20213445 21864708
2015 The D2 and D3 domains of eEF1A1 interact with the TPR domain of Sgt1; Sgt1 competes with viral RNA for binding to eEF1A1 in vitro. Co-immunoprecipitation with purified proteins and cell lysates, domain mapping, in vitro competition assay Biochimie Low 26545799
2015 Sgt1 heterozygous knockout suppresses Hras-mediated transformation in vitro and tumor formation in p53-/- MEFs; Sgt1 depletion destabilizes the EWS-FLI1 and PAX3-FOXO1 oncogenic fusion proteins in Ewing sarcoma and rhabdomyosarcoma cells, respectively. Sgt1 heterozygous knockout mouse, in vitro transformation assay, siRNA knockdown, protein stability assay Oncogenesis Medium 25985210

Source papers

Stage 0 corpus · 100 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2002 The RAR1 interactor SGT1, an essential component of R gene-triggered disease resistance. Science (New York, N.Y.) 469 11847307
2003 HSP90 interacts with RAR1 and SGT1 and is essential for RPS2-mediated disease resistance in Arabidopsis. Proceedings of the National Academy of Sciences of the United States of America 358 14504384
2007 A crucial function of SGT1 and HSP90 in inflammasome activity links mammalian and plant innate immune responses. Nature immunology 356 17435760
2002 Ubiquitin ligase-associated protein SGT1 is required for host and nonhost disease resistance in plants. Proceedings of the National Academy of Sciences of the United States of America 319 12119413
2002 Regulatory role of SGT1 in early R gene-mediated plant defenses. Science (New York, N.Y.) 318 11847308
1999 SGT1 encodes an essential component of the yeast kinetochore assembly pathway and a novel subunit of the SCF ubiquitin ligase complex. Molecular cell 315 10445024
2009 The HSP90-SGT1 chaperone complex for NLR immune sensors. Annual review of plant biology 286 19014346
2003 Molecular chaperone Hsp90 associates with resistance protein N and its signaling proteins SGT1 and Rar1 to modulate an innate immune response in plants. The Journal of biological chemistry 235 14583611
2006 Role of SGT1 in resistance protein accumulation in plant immunity. The EMBO journal 188 16619029
2003 Recognition specificity and RAR1/SGT1 dependence in barley Mla disease resistance genes to the powdery mildew fungus. The Plant cell 167 12615945
2007 Interaction between SGT1 and cytosolic/nuclear HSC70 chaperones regulates Arabidopsis immune responses. The Plant cell 158 18065690
2007 Structural and functional analysis of SGT1 reveals that its interaction with HSP90 is required for the accumulation of Rx, an R protein involved in plant immunity. The Plant cell 132 18032631
2007 SGT1 is essential for Nod1 activation. Proceedings of the National Academy of Sciences of the United States of America 121 17420470
2005 Molecular genetic evidence for the role of SGT1 in the intramolecular complementation of Bs2 protein activity in Nicotiana benthamiana. The Plant cell 119 15749757
2004 Expression of RPS4 in tobacco induces an AvrRps4-independent HR that requires EDS1, SGT1 and HSP90. The Plant journal : for cell and molecular biology 112 15447648
2007 The MI-1-mediated pest resistance requires Hsp90 and Sgt1. Plant physiology 106 17351050
2004 Human Sgt1 binds HSP90 through the CHORD-Sgt1 domain and not the tetratricopeptide repeat domain. The Journal of biological chemistry 101 14761955
2008 Structural and functional coupling of Hsp90- and Sgt1-centred multi-protein complexes. The EMBO journal 96 18818696
2020 A bacterial effector protein prevents MAPK-mediated phosphorylation of SGT1 to suppress plant immunity. PLoS pathogens 93 32976518
2010 Structural basis for assembly of Hsp90-Sgt1-CHORD protein complexes: implications for chaperoning of NLR innate immunity receptors. Molecular cell 89 20670895
2013 The Salmonella type III effector SspH2 specifically exploits the NLR co-chaperone activity of SGT1 to subvert immunity. PLoS pathogens 81 23935490
2004 Sgt1 is required for human kinetochore assembly. EMBO reports 71 15133482
2004 Sgt1 associates with Hsp90: an initial step of assembly of the core kinetochore complex. Molecular and cellular biology 69 15340069
2012 The Hsp90 co-chaperone Sgt1 governs Candida albicans morphogenesis and drug resistance. PloS one 66 22970302
2007 Plant signalling components EDS1 and SGT1 enhance disease caused by the necrotrophic pathogen Botrytis cinerea. The New phytologist 63 17547673
2003 Calcium-regulated interaction of Sgt1 with S100A6 (calcyclin) and other S100 proteins. The Journal of biological chemistry 59 12746458
2003 Role of SGT1 in the regulation of plant R gene signalling. Microbes and infection 59 12941389
2008 Structural and functional analysis of SGT1-HSP90 core complex required for innate immunity in plants. EMBO reports 51 18833289
2013 Nucleocytoplasmic partitioning of tobacco N receptor is modulated by SGT1. The New phytologist 50 23731343
2010 Hsp90-Sgt1 and Skp1 target human Mis12 complexes to ensure efficient formation of kinetochore-microtubule binding sites. The Journal of cell biology 49 20404110
2009 Sgt1, a co-chaperone of Hsp90 stabilizes Polo and is required for centrosome organization. The EMBO journal 46 19131964
2008 The mammalian CHORD-containing protein melusin is a stress response protein interacting with Hsp90 and Sgt1. FEBS letters 45 18474241
2007 Hsp70 is a new target of Sgt1--an interaction modulated by S100A6. Biochemical and biophysical research communications 44 17466273
2016 SGT1 is required in PcINF1/SRC2-1 induced pepper defense response by interacting with SRC2-1. Scientific reports 42 26898479
2010 SGT1 positively regulates the process of plant cell death during both compatible and incompatible plant-pathogen interactions. Molecular plant pathology 42 20695999
2008 Sgt1, but not Rar1, is essential for the RB-mediated broad-spectrum resistance to potato late blight. BMC plant biology 41 18215301
2020 Necdin regulates BMAL1 stability and circadian clock through SGT1-HSP90 chaperone machinery. Nucleic acids research 32 32667666
2010 SGT1 regulates wounding- and herbivory-induced jasmonic acid accumulation and Nicotiana attenuata's resistance to the specialist lepidopteran herbivore Manduca sexta. The New phytologist 31 21118264
2012 Plk1 phosphorylates Sgt1 at the kinetochores to promote timely kinetochore-microtubule attachment. Molecular and cellular biology 30 22869522
2021 Ralstonia solanacearum Type III Effector RipAC Targets SGT1 to Suppress Effector-Triggered Immunity. Plant & cell physiology 29 32991707
2020 Long noncoding RNA SAM promotes myoblast proliferation through stabilizing Sugt1 and facilitating kinetochore assembly. Nature communications 29 32483152
2007 TPR-Mediated self-association of plant SGT1. Biochemistry 27 17877371
2008 Sgt1 has co-chaperone properties and is up-regulated by heat shock. Biochemical and biophysical research communications 26 18358234
2008 Staying in the fold: The SGT1/chaperone machinery in maintenance and evolution of leucine-rich repeat proteins. Plant signaling & behavior 26 19513219
2009 Sgt1 dimerization is negatively regulated by protein kinase CK2-mediated phosphorylation at Ser361. The Journal of biological chemistry 25 19398558
2008 Sgt1 dimerization is required for yeast kinetochore assembly. The Journal of biological chemistry 25 19073600
2009 Enhanced defense responses in Arabidopsis induced by the cell wall protein fractions from Pythium oligandrum require SGT1, RAR1, NPR1 and JAR1. Plant & cell physiology 24 19304739
2010 SGT1 contributes to coronatine signaling and Pseudomonas syringae pv. tomato disease symptom development in tomato and Arabidopsis. The New phytologist 23 20854394
2023 1,8-cineole ameliorates colon injury by downregulating macrophage M1 polarization via inhibiting the HSP90-NLRP3-SGT1 complex. Journal of pharmaceutical analysis 22 37842654
2022 Melatonin Promotes SGT1-Involved Signals to Ameliorate Drought Stress Adaption in Rice. International journal of molecular sciences 22 35054782
2019 HSP90 and Its Novel Co-Chaperones, SGT1 and CHP-1, in Brain of Patients with Parkinson's Disease and Dementia with Lewy Bodies. Journal of Parkinson's disease 22 30741686
2014 Pathogen-induced SGT1 of Arachis diogoi induces cell death and enhanced disease resistance in tobacco and peanut. Plant biotechnology journal 21 25236372
2013 SGT1 regulates Akt signaling by promoting beta-TrCP-dependent PHLPP1 degradation in gastric cancer cells. Molecular biology reports 21 23440515
2006 Density of Sgt1-immunopositive neurons is decreased in the cerebral cortex of Alzheimer's disease brain. Neurochemistry international 21 16698122
2013 The Hv-SGT1 gene from Haynaldia villosa contributes to resistances towards both biotrophic and hemi-biotrophic pathogens in common wheat (Triticum aestivum L.). PloS one 20 24019872
2012 Sgt1 acts via an LKB1/AMPK pathway to establish cortical polarity in larval neuroblasts. Developmental biology 20 22248825
2014 Rpi-blb2-Mediated Hypersensitive Cell Death Caused by Phytophthora infestans AVRblb2 Requires SGT1, but not EDS1, NDR1, Salicylic Acid-, Jasmonic Acid-, or Ethylene-Mediated Signaling. The plant pathology journal 19 25289011
2024 Proxitome profiling reveals a conserved SGT1-NSL1 signaling module that activates NLR-mediated immunity. Molecular plant 18 39066482
2013 SGT1 interacts with the Prf resistance protein and is required for Prf accumulation and Prf-mediated defense signaling. Biochemical and biophysical research communications 18 23333384
2017 The crystal structure of the Sgt1-Skp1 complex: the link between Hsp90 and both SCF E3 ubiquitin ligases and kinetochores. Scientific reports 17 28139700
2015 The oncogenic role of the cochaperone Sgt1. Oncogenesis 17 25985210
2023 miR-141-3p alleviates ulcerative colitis by targeting SUGT1 to inhibit colonic epithelial cell pyroptosis. Autoimmunity 16 37317573
2021 Characterization of the Roles of SGT1/RAR1, EDS1/NDR1, NPR1, and NRC/ADR1/NRG1 in Sw-5b-Mediated Resistance to Tomato Spotted Wilt Virus. Viruses 16 34452313
2011 For security and stability: SGT1 in plant defense and development. Plant signaling & behavior 16 21897126
2022 Polycistronic baculovirus expression of SUGT1 enables high-yield production of recombinant leucine-rich repeat proteins and protein complexes. Protein expression and purification 15 35131438
2018 Molecular Co-Chaperone SGT1 Is Critical for Cell-to-Cell Movement and Systemic Infection of Tomato Spotted Wild Virus in Nicotiana benthamiana. Viruses 15 30453630
2018 Current view on cellular function of S100A6 and its ligands, CacyBP/SIP and Sgt1. Postepy biochemii 15 30656909
2015 Molecular chaperons and co-chaperons, Hsp90, RAR1, and SGT1 negatively regulate bacterial wilt disease caused by Ralstonia solanacearum in Nicotiana benthamiana. Plant signaling & behavior 14 25482800
2012 Scrib regulates HGF-mediated epithelial morphogenesis and is stabilized by Sgt1-HSP90. Journal of cell science 14 22623728
2004 Characterization of Rad6 from a higher plant, rice (Oryza sativa L.) and its interaction with Sgt1, a subunit of the SCF ubiquitin ligase complex. Biochemical and biophysical research communications 14 14733924
2020 SUGT1 controls susceptibility to HIV-1 infection by stabilizing microtubule plus-ends. Cell death and differentiation 13 32514048
2015 Translation elongation factor eEF1A1 is a novel partner of a multifunctional protein Sgt1. Biochimie 13 26545799
2014 Mutation of essential Hsp90 co-chaperones SGT1 or CNS1 renders yeast hypersensitive to overexpression of other co-chaperones. Current genetics 13 24923785
2012 Binding mechanism between Hsp90 and Sgt1 explored by homology modeling and molecular dynamics simulations in rice. Journal of molecular modeling 12 22653607
2021 Disruption of barley immunity to powdery mildew by an in-frame Lys-Leu deletion in the essential protein SGT1. Genetics 11 33724411
2020 SGT1 is not required for plant LRR-RLK-mediated immunity. Molecular plant pathology 11 33174685
2017 SGT1-HSP90 complex is required for CENP-A deposition at centromeres. Cell cycle (Georgetown, Tex.) 11 28816574
2014 Nematode Sgt1-homologue D1054.3 binds open and closed conformations of Hsp90 via distinct binding sites. Biochemistry 11 24660900
2013 Hsp90 and its co-chaperone, Sgt1, as autoantigens in dilated cardiomyopathy. Heart and vessels 11 22286152
2010 S100A6 mediates nuclear translocation of Sgt1: a heat shock-regulated protein. Amino acids 11 20213445
2017 Evaluation of Solasonine Content and Expression Patterns 
of SGT1 Gene in Different Tissues of Two Iranian Eggplant (Solanum melongena L.) Genotypes. Food technology and biotechnology 10 28867954
2017 Antifungal Effect of Arabidopsis SGT1 Proteins via Mitochondrial Reactive Oxygen Species. Journal of agricultural and food chemistry 10 28871788
2014 Emerging role of SGT1 as a regulator of NB-LRR-receptor nucleocytoplasmic partitioning. Plant signaling & behavior 10 24731991
2021 Genome-Wide Identification and Characterization of HSP90-RAR1-SGT1-Complex Members From Arachis Genomes and Their Responses to Biotic and Abiotic Stresses. Frontiers in genetics 9 34512718
2017 Interplay between the phosphatase PHLPP1 and E3 ligase RNF41 stimulates proper kinetochore assembly via the outer-kinetochore protein SGT1. The Journal of biological chemistry 9 28696259
2016 Characterization and abiotic stress-responsive expression analysis of SGT1 genes in Brassica oleracea. Genome 9 26966988
2010 Overexpression of SUGT1 in human colorectal cancer and its clinicopathological significance. International journal of oncology 9 20126976
2022 SGT1-Specific Domain Mutations Impair Interactions with the Barley MLA6 Immune Receptor in Association with Loss of NLR Protein. Molecular plant-microbe interactions : MPMI 8 34889653
2018 The Stoichiometric Interaction of the Hsp90-Sgt1-Rar1 Complex by CD and SRCD Spectroscopy. Frontiers in molecular biosciences 8 29387685
2005 The expression and function of Sgt1 protein in eukaryotic cells. Acta neurobiologiae experimentalis 8 15960300
2025 Wheat MAPK cascade mediates SGT1 nuclear entry targeted by a stripe rust effector. Journal of integrative plant biology 7 40062713
2016 Thermotolerance and molecular chaperone function of an SGT1-like protein from the psychrophilic yeast, Glaciozyma antarctica. Cell stress & chaperones 7 27154490
2023 Sugt1 loss in skeletal muscle stem cells impairs muscle regeneration and causes premature muscle aging. Life medicine 6 39872547
2016 Application of SGT1-Hsp90 chaperone complex for soluble expression of NOD1 LRR domain in E. coli. Biochemical and biophysical research communications 6 27591899
2014 Low-resolution structure of the full-length barley (Hordeum vulgare) SGT1 protein in solution, obtained using small-angle X-ray scattering. PloS one 6 24714665
2011 Nuclear translocation of Sgt1 depends on its phosphorylation state. The international journal of biochemistry & cell biology 6 21864708
2021 The role of chaperone complex HSP90-SGT1-RAR1 as the associated machinery for hybrid inviability between Nicotiana gossei Domin and N. tabacum L. Gene 5 33484759
2004 Molecular cloning and characterization of SGT1.2, a novel splice variant of Homo sapiens SGT1. DNA sequence : the journal of DNA sequencing and mapping 5 15346769
2025 The Role of Sgt1 in Methamphetamine/Hyperthermia-induced Necroptosis. Current medicinal chemistry 2 38204230
2024 SUGT1 regulates the progression of ovarian cancer through the AKT/PI3K/mTOR signaling pathway. Translational oncology 2 39167956