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Details on Person UniProt:P23640 Rab27a

Class:IdReferenceGeneProduct:99672
_chainChangeLoginitiator methionine:1 added on Fri February 6 2015;chain:2-221 added on Fri February 6 2015;initiator methionine:1 for 99672 removed on Fri Nov 03 2023;initiator methionine: for 99672 added on Fri Nov 03 2023;initiator methionine: for 99672 removed on Fri Aug 15 2025;initiator methionine:1 for 99672 added on Fri Aug 15 2025
_displayNameUniProt:P23640 Rab27a
_timestamp2026-02-20 22:15:03
chaininitiator methionine:1
chain:2-221
checksum6A3125DCC4738C80
commentFUNCTION The small GTPases Rab are key regulators of intracellular membrane trafficking, from the formation of transport vesicles to their fusion with membranes. Rabs cycle between an inactive GDP-bound form and an active GTP-bound form that is able to recruit to membranes different sets of downstream effectors directly responsible for vesicle formation, movement, tethering and fusion. RAB27A regulates homeostasis of late endocytic pathway, including endosomal positioning, maturation and secretion. Plays a role in cytotoxic granule exocytosis in lymphocytes. Required for both granule maturation and granule docking and priming at the immunologic synapse.CATALYTIC ACTIVITY GTP + H2O = GDP + phosphate + H(+)COFACTOR Regulated by guanine nucleotide exchange factors (GEFs) including DENND10, which promote the exchange of bound GDP for free GTP. Regulated by GTPase activating proteins (GAPs) which increase the GTP hydrolysis activity. Inhibited by GDP dissociation inhibitors (GDIs).SUBUNIT Binds SYTL1, SLAC2B, MYRIP, SYTL3, SYTL4 and SYTL5. Interacts with RPH3A and RPH3A (By similarity). Binds MLPH and SYTL2. Interacts with UNC13D. Does not interact with the BLOC-3 complex (heterodimer of HPS1 and HPS4) (By similarity). Interacts (GDP-bound form preferentially) with DENND10 (By similarity). Interacts with FBXO28; this interaction promotes RAB27A ubiquitination and proteasomal degradation (By similarity).SUBCELLULAR LOCATION Identified by mass spectrometry in melanosome fractions from stage I to stage IV. Localizes to endosomal exocytic vesicles.TISSUE SPECIFICITY High levels in eye, intestine, lung, pancreas and spleen, and low or absent in brain, liver, heart, kidney, and skeletal muscle.DOMAIN Switch I, switch II and the interswitch regions are characteristic of Rab GTPases and mediate the interactions with Rab downstream effectors. The switch regions undergo conformational changes upon nucleotide binding which drive interaction with specific sets of effector proteins, with most effectors only binding to GTP-bound Rab.PTM Ubiquitinated in a FBXO28-dependent manner; leading to proteasomal degradation.SIMILARITY Belongs to the small GTPase superfamily. Rab family.
descriptionrecommendedName: Ras-related protein Rab-27A shortName: Rab-27 ecNumber evidence="2"3.6.5.2 alternativeName: GTP-binding protein Ram alternativeName: fullName evidence="7"Ram p25
geneNameRab27a
Rab27
identifierP23640
isSequenceChangedFALSE
keywordAcetylation
Disulfide bond
Endosome
Exocytosis
GTP-binding
Hydrolase
Lipoprotein
Lysosome
Magnesium
Membrane
Metal-binding
Methylation
Nucleotide-binding
Phosphoprotein
Prenylation
Reference proteome
Ubl conjugation
modified[InstanceEdit:143527] Schmidt, EE, 2004-11-12 07:45:10
[InstanceEdit:217385] Schmidt, EE, 2008-03-27 06:23:53
[InstanceEdit:354386] Schmidt, EE, 2008-06-18 04:45:12
[InstanceEdit:384350] Kanapin, AA, 2008-11-26 14:00:39
[InstanceEdit:392885] Kanapin, AA, 2009-03-09 12:07:18
[InstanceEdit:400710] Schmidt, EE, 2009-03-25 05:33:35
[InstanceEdit:423310] Kanapin, AA
[InstanceEdit:435478] Kanapin, AA
[InstanceEdit:435871] Kanapin, AA
[InstanceEdit:447347] Kanapin, AA
[InstanceEdit:525883] Kanapin, AA
[InstanceEdit:613449] Kanapin, AA
[InstanceEdit:797602] Kanapin, AA
[InstanceEdit:937368] Yung, CK
[InstanceEdit:1042053] Yung, CK
[InstanceEdit:1220657] Yung, CK
[InstanceEdit:1300696] Yung, CK
[InstanceEdit:1301627] Yung, CK
[InstanceEdit:1551960] Weiser, JD
[InstanceEdit:1995863] Weiser, JD
[InstanceEdit:2132304] Weiser, JD
[InstanceEdit:2265580] Weiser, JD
[InstanceEdit:5263031] Weiser, JD
[InstanceEdit:5433710] Weiser, JD
[InstanceEdit:5618415] Weiser, JD
[InstanceEdit:5634237] Weiser, JD
[InstanceEdit:5673015] Weiser, JD
[InstanceEdit:8934940] Weiser, JD
[InstanceEdit:9037114] Weiser, JD
[InstanceEdit:9637257] Weiser, JD
[InstanceEdit:9657908] Weiser, JD
[InstanceEdit:9666080] Weiser, JD
[InstanceEdit:9676415] Weiser, JD
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9939033] Weiser, Joel, 2025-02-21
[InstanceEdit:9963647] Weiser, Joel, 2025-08-15
[InstanceEdit:9983091] Weiser, Joel, 2026-02-20
nameRab27a
referenceDatabase[ReferenceDatabase:2] UniProt
secondaryIdentifierRB27A_RAT
Q4KMA7
sequenceLength221
species[Species:48895] Rattus norvegicus
(referenceEntity)[EntityWithAccessionedSequence:8931588] Rab27a [cytosol] [Rattus norvegicus]
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