RAB33B

This gene encodes a small GTP-binding protein of the Rab GTPase family, whose members function in vesicle transport during protein secretion and endocytosis. Rab GTPases are active, membrane-associated proteins that recruit effector proteins in the GTP-bound state and inactive cytosolic proteins when in a GDP-bound state. The protein encoded by this gene is ubiquitously expressed and has been implicated in Golgi to endoplasmic reticulum cycling of Golgi enzymes. In addition, this protein regulates Golgi homeostasis and coordinates intra-Golgi retrograde trafficking. Allelic variants in this gene have been associated with Dyggve-Melchior-Clausen syndrome and Smith-McCort dysplasia 2, which are autosomal recessive spondyloepimetaphyseal dysplasias characterized by skeletal abnormalities. [provided by RefSeq, Sep 2016]

Full Name

RAB33B, member RAS oncogene family

Function

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.

Biological Process

Biological Process autophagosome assemblyIEA:Ensembl
Biological Process intra-Golgi vesicle-mediated transportManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process negative regulation of constitutive secretory pathwayManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process protein localization to Golgi apparatusManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process protein transportIEA:UniProtKB-KW
Biological Process Rab protein signal transductionIEA:InterPro
Biological Process regulation of exocytosisManual Assertion Based On ExperimentIBA:GO_Central
Biological Process regulation of Golgi organizationManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process regulation of retrograde vesicle-mediated transport, Golgi to ERManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process skeletal system morphogenesisManual Assertion Based On ExperimentIMP:UniProtKB

Cellular Location

Golgi apparatus membrane
Golgi apparatus, cis-Golgi network
Under starvation conditions punctate RAB33B-positive structures are often observed in the cytoplasm.

Involvement in disease

Smith-McCort dysplasia 2 (SMC2):
A rare autosomal recessive osteochondrodysplasia with skeletal features identical to those of Dyggve-Melchior-Clausen syndrome, but with normal intelligence and no microcephaly. It is characterized by short limbs and trunk with barrel-shaped chest. The radiographic phenotype includes platyspondyly, generalized abnormalities of the epiphyses and metaphyses, and a distinctive lacy appearance of the iliac crest.