Detailed entry information

Protein Information (annotations from UniProt)

Database IDHIV0004253
UniProt IDQ7LBR1
Primary gene name(s)CHMP1B
Synonym gene name(s)C18orf2
Protein nameCharged multivesicular body protein 1b
Protein functionProbable peripherally associated component of the endosomal sorting required for transport complex III, ESCRT-III which is involved in multivesicular bodies, MVBs formation and sorting of endosomal cargo proteins into MVBs. MVBs contain intraluminal vesicles, ILVs that are generated by invagination and scission from the limiting membrane of the endosome and mostly are delivered to lysosomes enabling degradation of membrane proteins, such as stimulated growth factor receptors, lysosomal enzymes and lipids. The MVB pathway appears to require the sequential function of ESCRT-O, -I,-II and -III complexes. ESCRT-III proteins mostly dissociate from the invaginating membrane before the ILV is released. The ESCRT machinery also functions in topologically equivalent membrane fission events, such as the terminal stages of cytokinesis and the budding of enveloped viruses, HIV-1 and other lentiviruses. ESCRT-III proteins are believed to mediate the necessary vesicle extrusion and/or membrane fission activities, possibly in conjunction with the AAA ATPase VPS4. Involved in cytokinesis. Involved in recruiting VPS4A and/or VPS4B and SPAST to the midbody of dividing cells. Involved in HIV-1 p6- and p9-dependent virus release. {ECO:0000269|PubMed:14519844, ECO:0000269|PubMed:19129479}.
Subcellular locationCytoplasm, cytosol. Endosome. Late endosome membrane {ECO:0000305};
Peripheral membrane protein {ECO:0000305}. Note=Localizes to the midbody of dividing cells, colocalizing with CEP55 and CHMP5. Localized at the periphery of the Fleming body.
ECO codeClick here for more information.
Amino acid sequence
FASTA format: Q7LBR1
Gene Ontology
(Biological Process)
Complete annatation
cell division [GO:0051301];
cell separation after cytokinesis [GO:0000920];
ESCRT III complex disassembly [GO:1904903];
establishment of protein localization [GO:0045184];
mitotic metaphase plate congression [GO:0007080];
multivesicular body assembly [GO:0036258];
nucleus organization [GO:0006997];
protein transport [GO:0015031];
regulation of centrosome duplication [GO:0010824];
regulation of mitotic spindle assembly [GO:1901673];
vacuolar transport [GO:0007034];
viral budding via host ESCRT complex [GO:0039702]
Gene Ontology
(Molecular Function)
Complete annatation
protein domain specific binding [GO:0019904]
Gene Ontology
(Cellular Component)
Complete annatation
cytosol [GO:0005829];
endosome membrane [GO:0010008];
ESCRT III complex [GO:0000815];
extracellular exosome [GO:0070062];
late endosome membrane [GO:0031902];
membrane coat [GO:0030117]
Protein-protein interaction121394
Phylogenetic treeQ7LBR1
HIV replication factor status Zhou et al., Cell. Host. Microbe., 2008
Brass et al., Science, 2008
Smith et al., J. Immunol, 2010
gene status
Lu et al., J. Virol., 2011
      Folds changes 8h: unknown; Folds changes 16h: unknown; Tested: unknown;
Schoggins JW and Rice CM, Curr. Opin. Virol., 2011
      Targeted viruses: unknown
      Viral life cycle: unknown
      Mechanism related to antiviral activity: unknown
Anti-viral restriction factor Liu et al., Retrovirology, 2011
      unknown (Triplicates)

Gene Expression Profile       top

            Up-regulated;            Down-regulated

For brief introduction to each study, please go to the help page.

Gene expression during HIV latency

(1). Mohammadi et al., PLoS Pathog., 2014

Differentially expressed transcripts (Pairwise) during latency and subsequent viral reactivation using several agents - Primary CD4+ T-cell based model

DMSO: Dimethyl suloxyde (negative control) - 0.0033% final
SAHA: Vorinostat (Histone deacetylase inhibitor) - 0.5 μM
CD3: TCR Stimulation by IL-2+ antiCD3/anti-CD28 antibodies
IL7: Interleukin-7 based stimulation
DISU: Disulfiram (alcohol dehydrogenase inhibitor) - 0.5 μM
AZA: 5-azacytidine (AZA; DNA methylation inhibitor) - 1 μM
Experimental Condition Log2 Fold Change P value Adjusted P value
AZA vs. CD3-0.2161265934629090.5092382492001870.625324987122797
AZA vs. DISU-0.02284509150611020.9280385984031960.995042856396371
AZA vs. IL7-0.1870704263937080.3316410732029630.999311006273513
AZA vs. SAHA0.06501192449600330.7899099356613710.944558334932533
DISU vs. CD30.1802719779211490.618757660084770.726815407703122
DISU vs. IL7-0.1734695802968670.4914048931343130.821205737251711
DISU vs. SAHA0.08940893080377180.7588752831129420.932068474683465
DMSO vs. AZA-0.02496158673900660.881803688784531
DMSO vs. CD30.1793691794654930.574822780605460.674694599908162
DMSO vs. DISU-0.004066000803438750.9867040427800220.997977034037055
DMSO vs. IL7-0.1549304138924530.3900673213244470.839677976433821
DMSO vs. SAHA0.08350769154883910.7232286185055610.918804561198458
HIV vs. Mock in Activation0.05530903564909820.9291383326829960.999983755607037
HIV vs. Mock in Latency0.1231054090700570.4557574093385350.999834320637052
IL7 vs. CD30.03644214865741290.9096453280280990.942731300149033
SAHA vs. CD30.2567511462274180.4674078152672770.579094777803539
SAHA vs. IL70.24867759578290.3078622071660440.556817355911322
(2). Iglesias-Ussel et al., J. Virol., 2013

Up and Downregulated transcripts during Latency (Latently infected CD4+ T cells vs Uninfected)- Primary CD4+Tcell based model
Log2 Fold Change P Value
unknown unknown

Gene expression during HIV infection and replication

(1). Imbeault et al., PloS Pathog., 2012

Transcriptomic profiling of HIV-1 infected CD4+ T cells - Primary CD4+ T cells
Experiment type Log2 Fold Change P Value Adjusted P Value
Infected vs. Mock unknown unknown unknown
Infected vs. Bystander unknown unknown unknown
(2). Lefebvre et al., J. Virol., 2011

Transcriptome analysis of T-cell line (Sup T1)
Log2 Fold Change unknown
(3). Li et al., J. Immunol., 2013

Lymphatic tissue
Acute Fold Change Acute P Value Asymt Fold Change Asypt P Value AIDS Fold Change AIDS P Value
unknown unknown unknown unknown unknown unknown
(4). Chang et al., MBio., 2011

Transcriptome analysis of T-cell line (Sup T1)

Derived from Sherrill-Mix et al., BMC Retrovirol., 2015 cross validation
Up-regulated (True) unknown
(5). Sherrill-Mix et al., BMC Retrovirol., 2015

Deep RNA-seq analysis of primary human T cell infected with low passage HIV isolate HIV89.6 - Primary CD4+ T cell based
Test Status Log2 Fold Change P Value
OK -0.28641 0.0497843
(6). Rotger et al., PLoS Pathog., 2010

Genome-wide mRNA expression of CD4+ T cells from HIV-infected patient
(Genes differentially expressed (at adjusted p<0.01) according to the empirical Bayes approach)
Log2 Fold Change P Value
unknown unknown

Proteomic/Transcriptomics studies indicating differentially expressed genes mediated by HIV

(1). Greenwood et al., Elife, 2016

Activated (CD3/CD28) Primary human CD4+ T cells infected with pNL4-3-dE-EGFP. The table shows the complete (unfiltered) TMT (tandem mass tag)-based proteomic time course dataset
6 h 24 h 48 h 72 h RTi
1.035 1.088 1.082 1.263 1.34
(2). Navare et al., Virology, 2012

SUP-T1 cell line
FC-4hpi P-value FC-8hpi P-value FC-20hpi P-value Category
unknown unknown unknown unknown unknown unknown unknown
(3). Hyrcza et al., J. Virolo., 2007

Primary human CD4+ and CD8+ T Cells
Affymetrix Prob ID Fold Change In CD8? Category
218177_at 1.4 No downregulated in CD8+ cells
218178_s_at 1.49 No downregulated in CD8+ cells

Protein Overview       top

Drug-protein Interaction       (annotations from DrugBank)      top

not found

Protein Secondary Structure       (annotations from PDB)      top

PDB Accession Method Resolution Chain Structure Preview
3EAB X-ray 2.5Å G/H/I/J/K/L=148-197.
3JC1 EM 4.0Å Ab/Ad/Af/Ah/Aj/Al/An/Ap/Ar/At/Av/Ax/Az/Bb/Bd/Bf/Bh/Bj/Bl/Bn/Bp/Br/Bt/Bv/Bx/Bz/Cb/Cd/Cf/Ch=4-163.
4TXQ X-ray 2.2Å C/D=176-199.
4TXR X-ray 1.0Å B=176-199.

HIV-1 Interaction       (annotations from NCBI HIV-1 Interaction Database)      top

HIV Partner Interaction Type PubMed
Pr55(Gag) co-localizes with 21394083

Metabolic/Signalling Pathway       (annotations from KEGG database)      top

Pathway Accession Number Description
hsa04144 Endocytosis - Homo sapiens (human)