| 1994 |
VIP36 (LMAN2) was purified from CHAPS-insoluble (glycolipid raft) fractions of MDCK cells and its cDNA was isolated; the N-terminal 31 kDa luminal domain shows homology to leguminous plant lectins. Transiently expressed VIP36 localizes to the Golgi apparatus, endosomal/vesicular structures, and the plasma membrane, consistent with a role in Golgi-to-cell-surface transport. |
Biochemical purification, cDNA cloning, immunofluorescence/subcellular localization of transiently expressed protein |
The EMBO journal |
Medium |
8157011
|
| 1996 |
The recombinant luminal/exoplasmic domain of VIP36 binds Ca2+ and can decorate internal membrane structures of MDCK cells in vitro; this binding requires Ca2+ and is specifically inhibited by N-acetyl-D-galactosamine. Glycopeptides from galactose-labeled cells bind to VIP36 and can be eluted with N-acetyl-D-galactosamine, demonstrating lectin activity. |
Recombinant protein production, Ca2+ binding assay, in vitro membrane-binding assay, affinity chromatography with competitive inhibition |
Journal of cell science |
Medium |
8834812
|
| 1999 |
Endogenous VIP36 localizes to the Golgi apparatus and the early secretory pathway (ER-Golgi intermediate compartment) of MDCK and Vero cells; it co-localizes with coatomer and ERGIC-53 and cycles in the early secretory pathway as shown by brefeldin A treatment and co-localization with anterograde cargo. |
High-resolution confocal microscopy, brefeldin A treatment, co-localization with marker proteins (endogenous protein) |
Journal of cell science |
Medium |
10444376
|
| 1999 |
VIP36 specifically recognizes high-mannose type glycans containing alpha1→2 mannosyl residues (Man7-9GlcNAc2) in a pH-optimum of 6.0; the interaction is Ca2+-independent and has an association constant of ~2.1×10^8 M^-1 with thyroglobulin glycans as measured by surface plasmon resonance. |
GST-fusion protein binding assay, inhibition studies with specific glycans, surface plasmon resonance biosensor |
Glycobiology |
High |
10406849
|
| 2002 |
VIP36 is localized to the apical membrane of polarized MDCK cells (apical/basolateral ratio ~2); overexpression of wild-type VIP36 increased apical transport and secretion of VIP36-recognized (high-mannose) glycoproteins (including clusterin), while a lectin-inactive mutant had no effect on glycoprotein distribution and inhibited secretion, demonstrating that VIP36 lectin activity is required for apical glycoprotein transport. |
VIP36 overexpression and lectin-dead mutant expression in polarized MDCK cells, measurement of apical/basolateral distribution and secretion rates |
The Journal of biological chemistry |
Medium |
11872745
|
| 2003 |
Endogenous VIP36 localizes to the trans-Golgi network, immature secretory granules, and mature secretory granules in rat parotid acinar cells, co-localizing with alpha-amylase in apical regions, indicating a post-Golgi secretory pathway role. |
Immunoelectron microscopy and double-staining immunofluorescence of rat parotid gland tissue (endogenous protein) |
The journal of histochemistry and cytochemistry |
Medium |
12871987
|
| 2004 |
VIP36 physically associates with alpha-amylase in parotid secretory vesicles via high-mannose type glycans; co-precipitation of alpha-amylase with VIP36 was abolished by endo H treatment (removing high-mannose glycans), and alpha-amylase in secretory vesicles carries high-mannose glycans. |
Subcellular fractionation (Percoll gradient), immunoelectron microscopy, co-immunoprecipitation with endo H treatment |
Glycobiology |
Medium |
15070860
|
| 2005 |
The carbohydrate recognition domain (CRD) of VIP36 selectively binds the deglucosylated trimannose of the D1 branch of high-mannose oligosaccharides with bell-shaped pH dependence (optimum ~6.5), consistent with binding in the cis-Golgi and releasing cargo in the ER (higher pH), suggesting a role in glycoprotein quality control. |
Frontal affinity chromatography (FAC) with pyridylaminated sugar library (21 oligosaccharides), recombinant CRD |
The Journal of biological chemistry |
High |
16129679
|
| 2007 |
Crystal structures of VIP36 luminal domain (CRD + stalk) in apo, Ca2+-bound, and mannosyl ligand-bound forms reveal a 17-stranded antiparallel beta-sandwich CRD; Ca2+ coordinates Asp131, Asn166, and His190 to enable carbohydrate binding; Man-α1,2-Man-α1,2-Man (D1 arm) is recognized by eight residues via extensive hydrogen bonds, explaining Ca2+-dependent and D1-arm-specific high-mannose glycoprotein recognition. |
X-ray crystallography of apo, Ca2+, and ligand-bound forms; structure-guided interpretation of substrate specificity |
The Journal of biological chemistry |
High |
17652092
|
| 2007 |
Frontal affinity chromatography comparing ERGIC-53, VIPL, and VIP36 CRDs showed that VIPL and VIP36 selectively bind deglucosylated trimannose of the D1 branch but with different pH dependence, while ERGIC-53 binds high-mannose oligosaccharides broadly. Structure-based mutagenesis showed that sugar-binding properties of these lectins can be switched by single amino acid substitutions. |
Frontal affinity chromatography with pyridylaminated sugar library; structure-based site-directed mutagenesis |
The Journal of biological chemistry |
High |
18025080
|
| 2007 |
VIP36 stably interacts with the ER chaperone BiP in an ATP-independent and carbohydrate-independent manner dependent on divalent cations; the interaction occurs in the ER (confirmed by immunoelectron microscopy) and is distinct from canonical chaperone-substrate interactions, suggesting a novel role for VIP36 in quality control of secretory proteins. |
Chemical crosslinking, co-immunoprecipitation, LC/MS/MS identification, immunoelectron microscopy, surface plasmon resonance with recombinant proteins; lectin-dead mutant used as control |
Glycobiology |
Medium |
17586539
|
| 2010 |
VIP36 interacts with alpha1-antitrypsin (alpha1-AT) specifically via its high-mannose glycans in Golgi and ER compartments (not the complex glycoform); silencing VIP36 accelerated alpha1-AT transport, arguing against an anterograde role and consistent with a post-ER quality control function where VIP36 recycles alpha1-AT from Golgi back to ER. |
YFP fragment complementation (bimolecular fluorescence complementation) screen of human liver cDNA library, mutagenesis of glycosylation sites, kifunensine treatment, VIP36 siRNA knockdown with transport kinetics |
Traffic (Copenhagen, Denmark) |
High |
20477988
|
| 2011 |
VIP36 is a target of ectodomain shedding on the cell surface (not in the Golgi/ER) in macrophages; the amount of VIP36 at the cell surface precisely regulates phagocytosis, and shedding of VIP36 is required for this regulation of phagocytic activity. |
Unbiased proteomic screening (LPS-stimulated macrophage conditioned media), cell surface shedding assay, VIP36 manipulation (overexpression/knockdown) with phagocytosis readout |
The Journal of biological chemistry |
Medium |
22016386
|
| 2012 |
VIP36 interacts with the receptor guanylyl cyclase GC-C; this interaction depends on glycosylation at specific sites that also allow GC-C to fold properly and bind ligand, identifying GC-C as the first receptor client of VIP36. |
Co-immunoprecipitation, mutagenesis of 10 glycosylation sites in GC-C, pharmacological inhibition of glycosylation |
The Journal of biological chemistry |
Medium |
23269669
|
| 2014 |
Crystal structure of ERGIC-53 CRD in complex with MCFD2 and α1,2-mannotriose revealed a shallower sugar-binding pocket in ERGIC-53 compared to VIP36 due to a single Asp-to-Gly substitution; this structural difference explains the broader sugar specificity of ERGIC-53 versus the D1-arm-specific binding of VIP36. |
X-ray crystallography of ERGIC-53 CRD/MCFD2/mannotriose complex; structural comparison with VIP36 |
PloS one |
High |
24498414
|
| 2016 |
LMAN2 (VIP36) is specifically required for the accumulation of the exosome cargo protein GPRC5B in the Golgi complex and restricts its transport along the exosomal pathway; LMAN2 may interfere with GGA1-mediated trans-Golgi network-to-endosome transport of GPRC5B. |
Inducible expression system for GPRC5B, LMAN2 knockdown, trafficking assay, co-localization, analysis of GGA1-mediated transport |
The Journal of biological chemistry |
Medium |
27765817
|
| 2024 |
LMAN2 co-expression with Kv1.2 causes a large depolarizing shift in channel activation voltage and deceleration of activation kinetics; shRNA knockdown of endogenous LMAN2 reduces Kv1.2 redox sensitivity and gating variability. Kv1.2 sensitivity to LMAN2 requires residues F251 and T252 in the intracellular S2-S3 linker, which also mediate redox-dependent gating, suggesting LMAN2 acts through the same pathway as extracellular redox modulation. |
Patch-clamp electrophysiology in CHO and L(tk-) cell lines, shRNA knockdown of endogenous LMAN2, Kv1.2 point mutations (F251, T252), functional screening of 52 candidate genes |
Function (Oxford, England) |
Medium |
39264045
|
| 2024 |
LMAN2 and the amino acid transporter Slc7a5 competitively modulate Kv1.2 gating in opposite directions; co-expression of both produces bimodal voltage-dependence suggesting two non-overlapping channel populations. Using Kv1.2:1.5 chimeras, distinct regions in S1-S3 of the voltage-sensing domain are required for LMAN2 versus Slc7a5 sensitivity, confirming that the two regulators compete for interaction with the Kv1.2 voltage sensor. |
Patch-clamp electrophysiology, Kv1.2:Kv1.5 chimeric channel approach, co-expression of LMAN2 and Slc7a5 |
FASEB journal |
Medium |
39659243
|
| 2024 |
VIP36 (LMAN2) is susceptible to ectodomain shedding followed by gamma-secretase-mediated intramembrane proteolysis (regulated intramembrane proteolysis, RIP); the C-terminal amino acids of its transmembrane domain regulate gamma-secretase susceptibility, as shown by substitution mutant analysis. VIPL, the close homolog, has different gamma-secretase susceptibility despite similar shedding. |
Substitution mutagenesis of transmembrane domain C-terminal residues, gamma-secretase processing assay, comparison with VIPL mutants |
Biochemical and biophysical research communications |
Medium |
38219489
|
| 2024 |
LMAN2 physically interacts with MAPK9 (JNK2) in breast cancer cells and activates the MAPK signaling pathway, promoting cisplatin resistance; knockdown of LMAN2 reduced MAPK pathway activation and sensitized drug-resistant cells to cisplatin in vivo. |
Co-immunoprecipitation, immunofluorescence co-localization, siRNA knockdown, tumor xenograft model |
Cancer medicine |
Low |
39618331
|