11q14.2 View the map and BAC clones (data from UCSC genome browser).
RAB38 (NM_022337): 3 exons, 62,169bp, Chr11: 87,534,584 - 87,596,752.
The figure below shows the structure of the known isoform (data from UCSC genome browser).
Search the 5'UTR and 1kb upstream regions (seq1=human SNAPAP, seq2=mouse Snapap) by CONREAL with 80% Position Weight Matrices (PWMs) threshold (view results here).
Tissue specificity: Expressed highly in melanocytes. The mRNA and the native protein were expressed in a tissue-specific manner, e.g., in the lung, skin, stomach, liver, and kidney. Freshly isolated rat alveolar type II cells were highly positive for the mRNA signal, but the signal was rapidly lost over time (Osanai, et al).
BMR: Bone marrow; SPL: Spleen; TMS: Thymus; BRN: Brain; SPC: Spinal cord; HRT: Heart; MSL: Skeletal muscle; LVR; Liver; PNC: Pancreas; PST: Prostate; KDN: Kidney; LNG: Lung. (data from GeneCards )
|Protein||NP_082514 (211aa)||NP_665717 (211aa)||04204 (167aa)||Q86PD0 (222aa)|
|Identities||97% /205aa||96% /203aa||73% /114aa||72% /127aa|
View multiple sequence alignment (PDF file) by ClustalW and GeneDoc.
(1) Domains predicted by SMART:
a) RAB: 10 - 180
(2) Transmembrane domains predicted by SOSUI: none.
(3) Graphic view of InterPro domain structure.
(1) Predicted results by ScanProsite:
a) Protein kinases ATP-binding region signature :
18 - 49: LGVGKTSIIKrYvhqnfsshyratigvd..FALK
b) ATP/GTP-binding site motif A (P-loop) : [occurs frequently]
16 - 23: GdlgvGKT
c) N-myristoylation site : [occurs frequently]
19 - 24: GVgkTS, 43 - 48: GVdfAL.
d) N-glycosylation site : [occurs frequently]
33 - 36: NFSS, 74 - 77: NMTR.
e) Protein kinase C phosphorylation site : [occurs frequently]
159 - 161: SaK, 199 - 201: SpK.
f) Casein kinase II phosphorylation site : [occurs frequently]
159 - 162: SakE.
(2) Predicted results of subprograms by PSORT II:
a) N-terminal signal peptide: none
b) KDEL ER retention motif in the C-terminus: none
c) ER Membrane Retention Signals: Found KKXX-like motif in the C-terminus: GCAK
d) VAC possible vacuolar targeting motif: none
e) Actinin-type actin-binding motif: type 1: none; type 2: none
f) Prenylation motif: S-farnesyl cysteine at 208
g) memYQRL transport motif from cell surface to Golgi: none
h) Tyrosines in the tail: none
i) Dileucine motif in the tail: none
(1) ModBase entry found, results here.
(2) ModBase predicted comparative 3D structure of P57729 from UCSC Genome Sorter.
From left to right: Front, Top, and Side views of predicted protein
This protein does not exist in the current release of SWISS-2DPAGE.
Computed theoretical MW=23,712Da, pI=7.65 (NP_071732).
(1) Biological process: intracellular protein transport
(2) GTPase activity.
(3) ATP binding; GTP binding
Immunofluorescence staining demonstrated that expressed GST-tagged Rab38 was mainly co-localized with endoplasmic reticulum-resident protein and also partly with intermittent vesicles between the endoplasmic reticulum and the Golgi complex. (Osanai, et al). Rab38 localizes to perinuclear vesicles carrying tyrosinase and tyrosinase-related protein 1 (Wasmeier, et al).
The RAB family of proteins is comprised of small GTP-binding proteins that transition between the cytoplasm and organelle membranes and are believed to regulate vesicle transport. The two-cysteine carboxy terminal motif important for the binding of lipid moieties differs from the consensus sequence found in other RAB proteins and is more like that found in RAS proteins. Varp (VPS9-ankyrin-repeat protein)/Ankrd27 specifically binds two small GTPases, Rab32 and Rab38. A conserved Val residue in the switch II region of Rab32(Val-92) and Rab38(Val-78) is required for Varp binding activity (Tamura, et al (2009); Tamura, et al (2011)).
RAB38 drosophila homolog CG8024/Rab-RP1 interaction information in CuraGen interaction database.
RAB38 is important in the vesicular trafficking that moves TYRP1 from the trans-Golgi network to the end-stage melanosome (Luftus, et al). Rab38 and Rab32 regulate a critical step in the trafficking of melanogenic enzymes, in particular, tyrosinase and TYRP1, from the TGN to melanosomes (Wasmeier, et al).