Ras-related protein Rab-33B (RAB33B)

The protein contains 229 amino acids for an estimated molecular weight of 25718 Da.

 

Protein transport. Acts, in coordination with RAB6A, to regulate intra-Golgi retrograde trafficking. It is involved in autophagy, acting as a modulator of autophagosome formation. (updated: April 1, 2015)

Protein identification was indicated in the following studies:

  1. Goodman and co-workers. (2013) The proteomics and interactomics of human erythrocytes. Exp Biol Med (Maywood) 238(5), 509-518.
  2. Hegedűs and co-workers. (2015) Inconsistencies in the red blood cell membrane proteome analysis: generation of a database for research and diagnostic applications. Database (Oxford) 1-8.
  3. Wilson and co-workers. (2016) Comparison of the Proteome of Adult and Cord Erythroid Cells, and Changes in the Proteome Following Reticulocyte Maturation. Mol Cell Proteomics. 15(6), 1938-1946.
  4. Chu and co-workers. (2018) Quantitative mass spectrometry of human reticulocytes reveal proteome-wide modifications during maturation. Br J Haematol. 180(1), 118-133.

Methods

The following articles were analysed to gather the proteome content of erythrocytes.

The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.

PublicationIdentification 1Uniprot mapping 2Not mapped /
Obsolete
TrEMBLSwiss-Prot
Goodman (2013)2289 (gene list)227853205992269
Lange (2014)123412347281224
Hegedus (2015)2638262202352387
Wilson (2016)165815281702911068
d'Alessandro (2017)18261817201815
Bryk (2017)20902060101081942
Chu (2018)18531804553621387

1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry

The compilation of older studies can be retrieved from the Red Blood Cell Collection database.

The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.

No sequence conservation computed yet.

Interpro domains
Total structural coverage: 100%
Model score: 99

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VariantDescription
SMC2
SMC2

The reference OMIM entry for this protein is 605950

Ras-associated protein rab33b; rab33b

DESCRIPTION

Small GTP-binding proteins of the RAB family, such as RAB33B, play important roles at defined steps of vesicular transport in protein secretion and the endocytosis pathway (Zheng et al., 1998).

CLONING

Zheng et al. (1998) cloned and characterized mouse Rab33b, a small GTP-binding protein closely related to RAB33A (300333), especially in the GTP-binding domain. The Rab33b gene encodes a 229-amino acid protein. Unlike mouse and human RAB33A, which have tissue-specific expression, Northern blot analysis indicated that mouse Rab33b is ubiquitously expressed. Using immunofluorescence studies, Zheng et al. (1998) showed that Rab33b is localized to the medial Golgi cisternae, suggesting that it may play a role in intra-Golgi transport.

GENE STRUCTURE

Zheng et al. (1998) determined that the mouse Rab33b gene contains 2 exons.

MAPPING

Gross (2013) mapped the RAB33B gene to chromosome 4q31.1 based on an alignment of the RAB33B sequence (GenBank GENBANK AF350420) with the genomic sequence (GRCh37).

MOLECULAR GENETICS

By exome sequencing of the proband in a consanguineous Saudi family segregating Smith-McCort syndrome linked to chromosome 4 (SMC2; 615222), Alshammari et al. (2012) identified a homozygous missense mutation in the RAB33B gene (K46Q; 605950.0001). Immunoblot analysis showed severe deficiency of RAB33B in patient cells compared with control cells, and patient fibroblasts also displayed a marked reduction in the immunofluorescence signal corresponding to RAB33B but comparable signal intensity to the Golgi marker giantin (602500). In a 22-year-old Turkish man with Smith-McCort syndrome-2, who had previously been reported by Neumann et al. (2006), Dupuis et al. (2013) identified a homozygous missense mutation in the RAB33B gene (N148K; 605950.0002). By Western blot analysis and immunofluorescence studies, Dupuis et al. (2013) found marked reduction of the RAB33B protein. ... More on the omim web site

Subscribe to this protein entry history

Feb. 2, 2018: Protein entry updated
Automatic update: Uniprot description updated

Dec. 19, 2017: Protein entry updated
Automatic update: Uniprot description updated

June 20, 2017: Protein entry updated
Automatic update: comparative model was added.

March 25, 2017: Additional information
No protein expression data in P. Mayeux work for RAB33B

March 16, 2016: Protein entry updated
Automatic update: OMIM entry 605950 was added.