Ask about this productRelated genes to: VAPB antibody
- Gene:
- VAPB NIH gene
- Name:
- VAMP associated protein B and C
- Previous symbol:
- -
- Synonyms:
- VAP-B, VAP-C, ALS8
- Chromosome:
- 20q13.32
- Locus Type:
- gene with protein product
- Date approved:
- 1999-03-19
- Date modifiied:
- 2019-04-23
Related products to: VAPB antibody
Related articles to: VAPB antibody
- Amyotrophic lateral sclerosis type 8 (ALS8), caused by the p.Pro56Ser mutation, is a rare familial motor neurone disease with an incompletely characterized profile. We aimed to characterize the clinical phenotype, upper motor neurone (UMN) sign prevalence, survival, and functional milestones. - Source: PubMed
Publication date: 2026/05/21
Marques Couto ChristianDe Melo Queiroz ElisaSouza Lima WaneskaCamilla De Lima Santos SavanaJosé Moreira Nascimento Osvaldo - In neurons, the endoplasmic reticulum (ER) forms an extensive network that establishes membrane contact sites (MCSs) with various organelles including the plasma membrane (PM). While MCSs are known to regulate lipid exchange and Ca signaling, their specific roles in synaptic transmission remain poorly understood. Here, we demonstrate that the ER resident proteins VAPA and VAPB are essential for organizing presynaptic Ca exchange and mobilizing synaptic vesicles. We show that the loss of VAP impairs Ca loading into both the ER and mitochondria during electrical activity. This regulation occurs primarily through VAP interactions with voltage-gated potassium channels (Kv2) at the PM. Our data suggest that the Kv2-VAP complex organizes presynaptic Ca signaling outside of the active zone. Without this scaffold, synaptic vesicles become trapped in the reserve pool and fail to participate in exocytosis. These findings reveal a novel role for Kv2-VAP MCSs in coordinating organelle Ca signaling and the synaptic vesicle cycle. - Source: PubMed
Publication date: 2026/05/07
Paton Cameron DHoppa Michael B - The endoplasmic reticulum (ER) is a highly dynamic intracellular organelle that forms close contact sites with other organelles and the plasma membrane. These membrane contact sites play essential roles in lipid exchange and calcium homeostasis. ER membrane proteins from the VAP, ORP, and ESYT families are key players in the formation and function of these contacts. Numerous interactions between these proteins are likely critical for their activity. We investigate the interactome between these protein families in live cells by analyzing two members from each family, using Förster Resonance Energy Transfer (FRET) between pairs of proteins labeled with fluorescent proteins (FP). FRET is detected by Fluorescence Lifetime Imaging Microscopy (FLIM). Our quantitative approach shows that all tested proteins clusterize and sometimes interact within their respective families, and that their organization at the nanometer scale can be disrupted by specific mutations or domain deletions. In particular, we show that the coiled-coil domains of ORP5 and ORP8 are required for the formation of both homomeric and heteromeric complexes. Moreover, we demonstrate that FRET-FLIM can detect intra-molecular conformational changes in response to alterations in the cellular environment, such as variations in Ca concentration, as observed for ESYT1. We also identify novel inter-family organization, including clustering between VAPB and ORP8, and between ESYT2 and ORP5/8. Finally, our approach highlights the broad interaction network (interactome) of VAPA/B, and shows how various potential binding partners can influence FRET efficiency. - Source: PubMed
Publication date: 2026/05/13
Zamiati DouniaAbdesselem MounaNüsse OliverErard Marie - People living with HIV develop persistent neurocognitive impairment despite viral suppression through incompletely defined mechanisms. HIV-1 Tat disrupts VAPB-PTPIP51 coupling at mitochondria-associated ER membranes via PTPIP51 tyrosine phosphorylation, causing VAPB relocalization away from MAMs, a causal mechanism established in our prior work. Here, we define the downstream metabolic consequences and establish VAPB as the critical determinant of neuronal lipid pathology. Lipidomic profiling identified triglycerides as the dominant altered species, comprising polyunsaturated forms normally destined for membrane synthesis or mitochondrial oxidation, consistent with membrane catabolism rather than de novo lipogenesis. Targeted metabolomics revealed bioenergetic collapse consistent with impaired mitochondrial oxidative function. The resulting lipid imbalance, including lipid droplet accumulation, produced secondary organellar dysfunction, including Golgi dispersal and ER stress. Critically, Tat failed to induce lipid droplet accumulation in shRNA-VAPB cells, while PTPIP51 silencing had no such protective effect, establishing that VAPB relocalization is the obligate trigger. Guanosine supplementation reduced lipid droplet accumulation, suggesting a link to bioenergetic failure that warrants further investigation. In postmortem HIV-infected frontal cortex, VAPB was paradoxically elevated yet correlated with worsening dementia severity, consistent with transcriptional upregulation that cannot overcome posttranslational blockade of VAPB-MAM localization. The polyunsaturated triglycerides, depleted plasmalogens, and elevated ceramides documented here closely parallel lipid signatures reported in PLWH with cerebrovascular complications, implicating Tat-driven lipid dysregulation as a candidate mechanism for the incompletely explained elevation in stroke risk in this population. - Source: PubMed
Publication date: 2026/05/04
Santerre MarylineArjona Sterling PCai Kathy QShcherbik NataliaSawaya Bassel E - Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a poor prognosis, in which the role of lipophagy, a selective autophagic process degrading lipid droplets (LDs), remains poorly characterized. This study investigated lipophagy and its key regulator, , in PDAC progression. Through immunofluorescence analysis of patient samples, transgenic mouse tissues, and cell lines, we find that lipophagy is elevated in PDAC and correlates with poor prognosis. Single-cell transcriptomic analysis identified as a critical lipophagy regulator and an independent clinicopathological indicator. Functional assays, including orthotopic and subcutaneous xenografts, demonstrated that promotes tumor growth. Mechanistically, OSBPL10 functionally cooperates with VAPA/VAPB to facilitate rapid lysosomal repair via ATG2A, thereby promoting lipophagy and lipid mobilization. Inhibition of lysosomal function abrogated the pro-lipophagic and pro-tumorigenic effects of OSBPL10. Collectively, our findings demonstrate that upregulated drives PDAC progression by enhancing lipophagy through ATG2A-mediated rapid lysosomal repair, highlighting OSBPL10 as a potential therapeutic target in PDAC. - Source: PubMed
Publication date: 2026/03/25
Duan ZonghaoMa XueshiyuYu FengZhang JunfengHua RongLiu WeiLiu DejunYang JianyuFu XueliangYang MinweiYao HongfeiJiang ShuhengHu LipengMutailifu MusitabaYang XiaomeiSun YongweiYao LinliHuo Yanmiao