Ask about this productRelated genes to: CHMP4B antibody
- Gene:
- CHMP4B NIH gene
- Name:
- charged multivesicular body protein 4B
- Previous symbol:
- C20orf178
- Synonyms:
- dJ553F4.4, Shax1, SNF7-2, VPS32B
- Chromosome:
- 20q11.22
- Locus Type:
- gene with protein product
- Date approved:
- 2001-07-17
- Date modifiied:
- 2015-08-27
Related products to: CHMP4B antibody
Related articles to: CHMP4B antibody
- Dendritic cells (DC) dysfunction impedes antitumor immunity, so understanding intrinsic regulators of DC antigen presentation and the resulting activation of antitumor CD8 T cells could benefit therapy. Here, we use a genome-wide CRISPR screen for antigen presentation-regulating genes in DCs, and identify estrogen receptor α (ERα) as an intrinsic checkpoint inhibiting antigen cross-presentation. ERα genomic deficiency or pharmacological degradation enhances antigen presentation and CD8 T cell priming in mouse and human DCs. Mechanistically, independently of canonical estrogen signaling, ERα sustains Galectin-3-mediated recruitment of CHMP4b to damaged phagosomes, thereby facilitating ESCRT-III-mediated membrane repair and restricting cytosolic antigen translocation. In vivo, ERα-deficient or ERα-degraded DC vaccines expand tumor-specific CD8 T cells to suppress tumor growth in mice bearing subcutaneous cancers. In vitro, FDA-approved ERα antagonists enhance human DC-mediated activation of antigen-specific human CD8 T cells. Our work thus uncovers a non-canonical role of ERα in phagosome integrity as a checkpoint for antigen cross-presentation in DCs, and implicates ERα-targeted DC vaccines as a potential immunotherapeutic strategy. - Source: PubMed
Publication date: 2026/05/05
Liu YaxinMa ZhongfeiLi XuelianDing YuanyuanLi ZhiqingZhang BinZhou YumeiZhou JunLiu ShuoLiu ShuxunZhang LianjunWang ChunmeiCao Xuetao - Toxin A and B from Clostridioides difficile are the main pathogenicity factors for clinical symptoms of C. difficile infections. Receptor-mediated endocytosis and endosomal escape are required for targeting substrate proteins of the Rho-GTPase family. We previously reported that Toxin B (TcdB) affects endo-lysosomal transport and autophagic flux of target cells. These effects are independent from pathogenic Rho inhibition. Here, we aimed at further characterization of this event by immunofluorescent characterization of the vesicular structures that are affected. We found large aggregates of damaged endolysosomal structures positive for EEA1, LAMP1, CHMP4B and TcdB, as well as an increase in perinuclear concentration of non-mature autophagosomes (amphisomes) positive for SQSTM, Rab7, and LC3B. We investigated whether Rab7, a regulator of late endosome transport, is causative for decreased lysosome function. Although TcdB induced an increase in active Rab7, as tested by an RILP pull-down assay, inhibition of Rab7 did not prevent TcdB-induced decrease in cathepsin D as a surrogate for lysosome dysfunction. It also indicates that the observed increase in Rab7 positive amphisomes is secondary to lysosomal dysfunction. By applying an autoproteolytic deficient mutant of TcdB we proved that the release of the glucosyltransferase domain is mandatory for triggering all of these effects. This suggests that after membrane perforation the toxin remnants leave an open leak in endolysosomes affecting ion homeostasis. Investigation of all large clostridial glucosyltransferases and other toxins revealed lysosomal dysfunction as a general effect of many but not of all toxins that integrate into the endosome membrane. - Source: PubMed
Publication date: 2026/04/15
Langejürgen AnnaSchmidt GudulaUnsöld LeonTatge HelmaOyson EthelGerhard Ralf - Cells actively maintain complex lipidomes that encompass thousands of lipids; however, many of the roles of these lipids remain unexplored. Specific interactions between lipids and membrane proteins are a likely reason for lipidome complexity. Here we report the development of a technique, named lipid-trap mass spectrometry (LTMS), to systematically study lipid-protein interactions directly captured from mammalian cells. LTMS uses immunoprecipitation of GFP-tagged proteins expressed in HeLa cells, followed by lipidomic analysis of lipids bound to the GFP-tagged protein. We applied LTMS to cell division to illustrate the technique. We chose this process because membranes regulate their lipid composition as they undergo major changes during cytokinesis, and many cytokinetic proteins, including RACGAP1 and ESCRT-III components CHMP4B and CHMP2A, are membrane-associated. Using LTMS, we found that RACGAP1 and CHMP4B associate with specific lipid species in dividing compared with non-dividing cells. We expand our understanding of lipid diversity during cell division and present a general approach to explore lipid-protein interactions to further our knowledge of the roles of lipids in mammalian cells. - Source: PubMed
Publication date: 2026/04/13
Paquola AndreaBenson Clare EDesale Smita EknathOzbalci CagakanStorck Elisabeth MTerry Stephen JRao Bhagyashree DasariNwite Kelechi NFerrentino FedericaEggert Ulrike S - Endomembrane damage of intracellular vesicles triggers signals that activate membrane repair in mammalian cells to restore homeostasis. However, the signals that drive diverse membrane repair recruitment at the individual organelle level are unknown. Here by recording Ca leakage history with a newly developed Ca probe in human macrophages, we discovered that Ca²⁺ leakage serves as a conserved signal that triggers ATG8/LC3 lipidation after different types of sterile membrane damage. The damaged compartments consisted of both single membrane and multilayered membrane structures undergoing extensive membrane remodelling. We show the complexity and acidification of these ATG8/LC3-positive compartments depends on the nature of the membrane damage trigger. Functionally, the formation of these multimembrane ATG8/LC3-positive compartments restricted membrane damage independently of canonical autophagy and the recruitment of ESCRT components CHMP2A/CHMP4B. Altogether, we show that endolysosomal Ca²⁺ leakage triggers non-canonical LC3 lipidation on damaged membranes to promote membrane repair in human macrophages. - Source: PubMed
Publication date: 2026/03/20
Chen DiFearns AntonyPeddie Christopher JGutierrez Maximiliano G - Transverse tubules (T-tubules) are invaginations of the plasma membrane crucial for excitation-contraction coupling. Disruptions in T-tubule organization are frequently observed in heart diseases and are associated with impaired contractile function and malignant arrhythmias. In mammalian cells, the ESCRT (endosomal sorting complex required for transport) proteins mediate a fundamental mechanism for membrane deformation. This study aimed to elucidate the roles of key ESCRT proteins, including Chmp4b (charged multivesicular body protein 4b) and Tsg101 (tumor susceptibility gene 101), in the formation and maintenance of T-tubules. - Source: PubMed
Publication date: 2026/03/20
Wang XinjianHan ShuxianZhang GeHuang XiaozhiXu ChenZhang JiayinZheng YuyuanZhao PengweiLin TaoFeng ZijianHall Duane DSun QimingZhou ChunWu Hong-KunSong Long-ShengHan Peidong