RAB27

RAB27A, member RAS oncogene family
Identifiers
Symbol	RAB27A
Entrez	5873
HUGO	9766
OMIM	603868
RefSeq	NM_004580
UniProt	P51159
Other data
Locus	Chr. 15 q21

RAB27B, member RAS oncogene family
Identifiers
Symbol	RAB27B
Entrez	5874
HUGO	9767
OMIM	603869
RefSeq	NM_004163
UniProt	O00194
Other data
Locus	Chr. 18 q21.2

Rab27 is a member of the Rab subfamily of GTPases. Rab27 is post translationally modified by the addition of two geranylgeranyl groups on the two C-terminal cysteines.

Pathology

Mutations that prevent the expression of Rab27 ('knock out' mutations) cause the hypopigmentation and immunodefficiency disorder known as type II Griscelli syndrome, while a decrease in Rab27 prenylation is thought to be involved in choroideremia.

The symptoms of type II Griscelli syndrome have shown that Rab27 is involved in melanosome transport in melanocytes and in cytotoxic killing activity in cytotoxic T lymphoblasts. In melanocytes Rab27 binds the melanosome. The melanosome is transported along the microtubule. Rab27 then recruits Slac2A and myosin Va, these enzymes are essential for the transfer of the melanosomes from the microtubules to actin filaments. The melanosomes can now continue on their path towards the cell periphery. If either Rab27, Slac2A or myosin Va are absent then the melansomes remain in the perinuclear region of the cell. This disruption in pigmentation results in the hypopigmentation seen in the silvery hair colour of patients with Griscelli syndrome.

External links

RAB27A protein, human at the US National Library of Medicine Medical Subject Headings (MeSH)
RAB27B protein, human at the US National Library of Medicine Medical Subject Headings (MeSH)

Hydrolases: acid anhydride hydrolases (EC 3.6)

3.6.1

3.6.2

3.6.3-4: ATPase

3.6.3

Cu++ (3.6.3.4)	Menkes/ATP7A Wilson/ATP7B

Ca+ (3.6.3.8)	SERCA ATP2A1 ATP2A2 ATP2A3 Plasma membrane ATP2B1 ATP2B2 ATP2B3 ATP2B4 SPCA ATP2C1 ATP2C2

Na+/K+ (3.6.3.9)	ATP1A1 ATP1A2 ATP1A3 ATP1A4 ATP1B1 ATP1B2 ATP1B3 ATP1B4

H+/K+ (3.6.3.10)	ATP4A

Other P-type ATPase	ATP8B1 ATP10A ATP11B ATP12A ATP13A2 ATP13A3

3.6.4

3.6.5: GTPase

3.6.5.1: Heterotrimeric G protein	G_αs G_αi GNAI1 GNAI2 GNAI3 G_αq/11 GNAQ GNA11 G_α12/13 GNA12 GNA13 Transducin GNAT1 GNAT2 Gustducin GNAT3

3.6.5.2: Small GTPase > Ras superfamily	Rho family of GTPases: Cdc42 CDC42 TC10 TCL RhoUV RhoU RhoV Rac Rac1 2 3 RhoG RhoBTB 1 2 RhoH Rho A B C Rnd 1 2 3 RhoDF RhoF RhoD other: Ras HRAS KRAS NRAS Rab RAB23 RAB27 Arf ARF6 SAR1B ARL13B ARL6 Ran Rheb Rap RGK

3.6.5.3: Protein-synthesizing GTPase	Prokaryotic IF-2 EF-Tu EF-G Eukaryotic

3.6.5.5-6: Polymerization motors	Dynamin Tubulin

Enzymes

Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Catalytically perfect enzyme Coenzyme Cofactor Enzyme catalysis Enzyme kinetics Lineweaver–Burk plot Michaelis–Menten kinetics

Regulation	Allosteric regulation Cooperativity Enzyme inhibitor

Classification	EC number Enzyme superfamily Enzyme family List of enzymes

Types	EC1 Oxidoreductases (list) EC2 Transferases (list) EC3 Hydrolases (list) EC4 Lyases (list) EC5 Isomerases (list) EC6 Ligases (list)

This article is issued from Wikipedia - version of the 1/27/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.