Isolation, expression pattern of a novel human RAB gene RAB41 and characterization of its intronless homolog RAB41P
DNA SEQUENCE
Authors: Guo, JH; Chen, L; Chen, S; Liu, X; Saiyin, H; Deng, Q; Zhuang, Y; Wan, B; Yu, L; Zhao, SY
Abstract
Small GTPases form a big family including Ras, Rho, Rac, Rab, Sar1/Arf subfamilies and Ran homologs, playing important roles in diverse cellular processes. Through data mining, a novel human RAB41 gene was predicted and subsequently isolated from human testis. The open reading frame of RAB41 is 636 bp in length. RAB41 was composed of three exons, and it was mapped to chromosome 3q21.3 by comparing with the human genomic data. RAB41 protein contains a RAB domain. Similarity analysis indicated that RAB41 is closely similar to RAB19. The results of PCR amplification indicated that human RAB41 is widely expressed in brain, testis, lung, heart, ovary, colon, kidney, uterus and spleen but not in liver. By genomic searching, an intronless pseudogene homologous to RAB41 at chromosome 16 -- RAB41P was identified at human chromosome 16q11.2. Flanking the pseudogene RAB41P in human genome, there exist some transposable elements LINEs -- L1, whose contribution in the generation of this intronless homolog is discussed.
Toward a Comprehensive Map of the Effectors of Rab GTPases
DEVELOPMENTAL CELL
Authors: Gillingham, Alison K.; Sinka, Rita; Torres, Isabel L.; Lilley, Kathryn S.; Munro, Sean
Abstract
The Rab GTPases recruit peripheral membrane proteins to intracellular organelles. These Rab effectors typically mediate the motility of organelles and vesicles and contribute to the specificity of membrane traffic. However, for many Rabs, few, if any, effectors have been identified; hence, their role remains unclear. To identify Rab effectors, we used a comprehensive set of Drosophila Rabs for affinity chromatography followed by mass spectrometry to identify the proteins bound to each Rab. For many Rabs, this revealed specific interactions with Drosophila orthologs of known effectors. In addition, we found numerous Rab-specific interactions with known components of membrane traffic as well as with diverse proteins not previously linked to organelles or having no known function. We confirm over 25 interactions for Rab2, Rab4, Rab5, Rab6, Rab7, Rab9, Rab18, Rab19, Rab30, and Rab39. These include tethering complexes, coiled-coiled proteins, motor linkers, Rab regulators, and several proteins linked to human disease.