RAB2B

RAB2B 3D structure (2A5J)

RAB2B is a protein required for protein transport from the endoplasmic reticulum to the Golgi complex. It belongs to the small GTPase superfamily, specifically to the RAB protein family.

Structure

RAB2B is a human protein which gene is located in the fourteenth chromosome. It has a core made of basic elements such as oxygen, carbon, nitrogen, phosphorus and magnesium. Its tertiary structure disposes the 216 amino acids this protein is made of in eight alpha helix and six beta strands. A mature RAB2B suffers three post-translational modifications, a phosposerine is found in the location 202 instead of a normal serine, and two lipidations can be found in locations 215-216. It has a motif domain between the amino acids 35 and 43. Due to the alternative splicing, two isoforms of this same protein exist.

Biological activity

Small GTPases of the RAB superfamily are recognized as key players of the protein machinery involved in vesicular transport and organelle dynamics in eukaryotic cells. RAB2B follows mainly exocytic pathways, from the endoplasmic reticulum to Golgi complex. RAB proteins are involved in docking and fusion of transport vesicles with their target membranes.

Relevance

The results of the latest research show that RAB2B isoform knockdown affected the morphology of the Golgi complex in mammls, inducing its fragmentation. Even though these RAB family proteins are highly homologous to each other (RAB2A and RAB2B have 85.8% amino acid identity), the knockdown of any of them (from RAB1A to RAB8A) causes Golgi complex to disperse throgh cytoplasm.