| 2013 |
Crystal structures of human SUV420H1 (KMT5B) and SUV420H2 in complex with SAM revealed a unique N-terminal domain and Zn-binding post-SET domain; both enzymes prefer monomethylated H4K20me1 as substrate and produce only dimethylated product in vitro; a conserved serine residue forms a hydrogen bond with the target lysine side-chain that limits methylation to the dimethyl level (no trimethylation detected). |
X-ray crystallography; radioactivity-based in vitro methyltransferase assay |
FEBS letters |
High |
24396869
|
| 2016 |
In vitro SPOT peptide array analysis defined the substrate sequence recognition motif of SUV420H1 as (RY)-Kme1-(IVLM)-(LFI)-X-D, confirming strong preference for monomethylated H4K20 and production of only dimethylated product; novel non-histone substrates including K1423 of CASZ1 were identified for SUV420H1; SUV420H1 was found NOT to methylate ERK1 at K302/K361 under these conditions. |
In vitro methylation assay with peptide substrates; SPOT peptide array |
Journal of molecular biology |
High |
27105552
|
| 2015 |
SUV420H1 was reported to trimethylate ERK1 at lysines 302 and 361 in cancer cells; substitution of these methylation sites diminished ERK1 phosphorylation; SUV420H1 knockdown reduced phosphorylated ERK1 protein and suppressed ERK1 at the transcriptional level. |
In vitro methyltransferase assay; site-directed mutagenesis of ERK1 methylation sites; siRNA knockdown with Western blot and qRT-PCR |
Oncotarget |
Low |
26586479
|
| 2019 |
Eight somatic cancer mutations in SUV420H1 modulate its catalytic activity: group 1 mutations (S255F, K258E, A269V) reduce activity on both peptide and nucleosome substrates implicating roles in AdoMet binding and H4-D24 recognition; group 2 mutations (E238V, D249N, E320K) reduce peptide activity but are partially rescued on nucleosome substrates; group 3 mutations (S283L, S304Y) enhance activity on peptides but not nucleosomes, implicating nucleosomal contacts in allosteric activation; seven of eight mutations reduce cellular H4K20me2/3. |
In vitro methyltransferase assay on peptide and nucleosome substrates; cellular assays after mutant expression |
Journal of molecular biology |
Medium |
31255706
|
| 2010 |
Two isoforms of SUV420H1 (i1 and i2) differ in subcellular localization: exogenous SUV420H1_i2 distributes throughout the nucleus independent of HP1α, while SUV420H1_i1 and SUV420H2 associate with constitutive heterochromatin and are further targeted to pericentromeric regions by HP1α co-expression. SUV420H1_i2 elevation increases global nuclear H4K20me3, whereas SUV420H1_i1/SUV420H2 preferentially increase pericentric H4K20me3. SUV420H1_i2 induces precocious myogenin expression, while SUV420H1_i1 cannot be expressed in C2C12 cells suggesting post-transcriptional/translational control. |
Immunofluorescence; co-expression with HP1α; overexpression in C2C12 myogenic model; immunoblot for H4K20me3 |
PloS one |
Medium |
21206904
|
| 2013 |
SUV420H1 physically binds FRG1 (FSHD region gene 1) when FRG1 is overexpressed; this interaction inhibits Suv4-20h1 histone methyltransferase activity; Suv4-20h1 knockdown mimics FRG1 overexpression in blocking myogenesis; Suv4-20h KO mice develop muscular dystrophy-like signs; the FRG1/Suv4-20h1 target gene Eid3 was identified as a myogenic inhibitor downstream of this pathway. |
Co-immunoprecipitation; in vitro methyltransferase assay; siRNA knockdown; KO mouse model; genetic epistasis |
Journal of molecular cell biology |
Medium |
23720823
|
| 2023 |
Cryo-EM structures of SUV420H1 bound to H2A.Z-nucleosome and H2A-nucleosome revealed that: (1) SUV420H1 contacts the H4 N-terminal tail (residues 1–24) in a lasso-shaped structure that projects H4K20 into the catalytic center; (2) SUV420H1 interacts with nucleosomal DNA and the acidic patch; (3) a KR loop (residues 214–223) of SUV420H1 contacts H2A.Z-specific residues D97/S98, providing the structural basis for preferential recognition of H2A.Z-nucleosome and enhanced H4K20me2 deposition. |
Cryo-EM structure determination; in vitro methyltransferase assay; mutagenesis of KR loop and H2A.Z-specific residues; in vivo ChIP |
Molecular cell |
High |
37536340
|
| 2023 |
Cryo-EM structures of SUV420H1 on H2A- and H2A.Z-nucleosomes showed SUV420H1 makes extensive contacts with histone and DNA; the C-terminal domain uses two arginine anchors to engage the H2A-H2B acidic patch, enabling H4K20 insertion for catalysis; additional residues near the H2A.Z interface enhance catalytic activity on H2A.Z-NCPs; disease-associated mutations at interfaces impair catalytic activity and chromatin state regulation in vitro and in vivo. |
Cryo-EM; in vitro methyltransferase assay; mutagenesis; in vivo functional assays |
Cell discovery |
High |
38052811
|
| 2023 |
Cryo-EM and biochemical analyses showed SUV420H1 binding to nucleosomes causes dramatic detachment of nucleosomal DNA from the histone octamer (a non-catalytic activity), and SUV420H1 can promote chromatin condensation (another non-catalytic activity); H2A.Z stimulates SUV420H1 catalytic activity; deletion and inhibition of SUV420H1 produce distinct phenotypes, supporting functionally significant non-catalytic roles. |
Cryo-EM; biochemical and biophysical assays; cellular assays comparing deletion versus catalytic inhibition |
Molecular cell |
High |
37595555
|
| 2018 |
SUV420H1 (Suv4-20h1) directly binds the promoter of the p21WAF1/CIP1 gene and deposits H4K20 methylation there; knockdown of Suv4-20h1 in K562 cells causes G1 arrest accompanied by increased p21 expression, demonstrating a role in G1-to-S phase transition via epigenetic repression of p21. |
siRNA knockdown; chromatin immunoprecipitation (ChIP); cell cycle analysis; Western blot |
Oncology letters |
Medium |
29616094
|
| 2021 |
SUV420H1 (Suv4-20h1) directly binds the 5′-upstream regulatory element of the Sod3 (superoxide dismutase 3) gene to repress its expression in cardiopulmonary progenitor cells; conditional Suv4-20h1 knockout in these progenitors causes increased SOD3 protein leading to elevated H2O2, vascular defects, impaired alveolarization, and a COPD-like/PH phenotype in mice. |
Conditional knockout mouse (Cre-lox); ChIP; biochemical assays for SOD3 and H2O2; histology and hemodynamic studies |
Circulation |
High |
34247492
|
| 2021 |
Knockdown of Kmt5b in mouse prefrontal cortex reduces H4K20me2, which impairs 53BP1-mediated DNA repair, leading to elevated p53 and its target Ddit4 (Redd1), resulting in reduced synaptic expression of glutamate receptor subunits, deficits in glutamatergic synaptic transmission, and social behavior deficits. |
In vivo shRNA knockdown in mouse PFC; Western blot; immunofluorescence; electrophysiology; RNA-seq |
Neuropsychopharmacology |
Medium |
34007043
|
| 2021 |
In vivo loss of Suv4-20h1 in skeletal muscle satellite cells abolishes H4K20me2 on the distal regulatory element of the Myod locus, relocating the Myod locus toward the nuclear center, reducing facultative H3K27me3-associated heterochromatin, and causing spontaneous satellite cell activation and failure of self-renewal upon muscle injury. |
Conditional knockout in satellite cells; immunofluorescence; ChIP; FISH; muscle injury/regeneration assay |
Stem cell investigation |
Medium |
27488816
|
| 2022 |
In vitro knockdown of Kmt5b in mouse primary cortical neurons decreases dendritic complexity and increases dendritic spine density, effects rescued by wild-type human KMT5B but not by pathogenic de novo missense variants; in utero electroporation knockdown of Kmt5b in embryonic cerebral cortex reduces neural progenitor proliferation and accelerates migration. |
shRNA knockdown in primary neurons; in utero electroporation; morphological analysis (Sholl analysis, spine density); rescue with WT vs. mutant KMT5B |
Journal of genetics and genomics |
Medium |
35331928
|
| 2023 |
Depletion of SUV420H1 alone in Xenopus embryos is sufficient to cause loss of cilia in multiciliated cells (MCCs); the catalytic activity of SUV420H1 is required for axoneme formation; MCC precursor specification and centriole amplification occur normally but ciliogenesis fails; overexpression of catalytically active PHF8 (H4K20me1 demethylase) rescues the ciliogenic defect, indicating that conversion of H4K20me1 to H4K20me2 by SUV420H1 is mechanistically critical for cilia formation. |
Morpholino knockdown in Xenopus; catalytic mutant rescue; PHF8 overexpression rescue; genome-wide transcriptome profiling; phenotypic analysis of cilia |
Life science alliance |
Medium |
37116939
|
| 2026 |
Single knockdown of KMT5B (not KMT5C) in Xenopus leads to aberrant transcription and downregulation of ciliary genes without globally compacting chromatin at ciliary gene loci (ATAC-seq shows few differentially accessible peaks); the phenotype is rescued by catalytically active PHF8 but not by multicilin overexpression, demonstrating KMT5B regulates multiciliogenesis through an alternative pathway independent of the canonical multicilin-driven program. |
Morpholino knockdown in Xenopus; ATAC-seq; RNA-seq; catalytic mutant rescue; PHF8 and multicilin overexpression |
Life science alliance |
Medium |
41946567
|
| 2025 |
Mutant p53(R280T) binds the KMT5B promoter and specifically upregulates KMT5B expression, leading to enhanced DNA repair capacity and 5-FU resistance in nasopharyngeal carcinoma; depletion of KMT5B restores 5-FU-induced DNA damage and improves chemosensitivity. |
Chromatin immunoprecipitation (p53 binding to KMT5B promoter); siRNA knockdown; Western blot; cell viability/clonogenic assays; xenograft model |
Cancer letters |
Medium |
40316196
|
| 2025 |
Two missense variants in KMT5B (p.Gly94Ser and p.Ala293Pro) significantly reduce KMT5B protein stability and expression; KMT5B knockdown in HEK293T cells upregulates DDR proteins p53, DDIT4, and γH2AX; overexpression of wild-type KMT5B normalizes these DDR proteins, but the variants fail to do so, with persistent γH2AX foci indicating impaired DNA damage response. |
Western blot; immunofluorescence; stable cell line overexpression; siRNA knockdown |
QJM |
Medium |
41442178
|
| 2025 |
Depletion of SUV420H1 in HPV-negative HNSCC cell lines decreases proliferation, cell cycling, and invasion; enzymatic inhibition decreases invasion but not proliferation/cell cycling, demonstrating catalytically-independent and -dependent functions; Suv420h1 knockout in MOC1 cells halted tumor growth and synergized with anti-PD-1 therapy; genome-wide H4K20me3 mapping showed enrichment at EMT, IFN-response, and myeloid-attracting chemokine gene loci. |
siRNA/shRNA depletion; enzymatic inhibitor treatment; invasion/proliferation assays; syngeneic mouse KO model; ChIP-seq for H4K20me3 |
bioRxivpreprint |
Medium |
41473330
|