RRC ID 48878
著者 Fukuda M.
タイトル Alternative splicing in the first alpha-helical region of the Rab-binding domain of Rim regulates Rab3A binding activity: is Rim a Rab3 effector protein during evolution?
ジャーナル Genes Cells
Abstract Rim1 and Rim2 were originally described as specific Rab3A-effector proteins involved in the regulation of secretory vesicle exocytosis. The putative Rab3A-binding domain (RBD) of Rim consists of two alpha-helical regions (named RBD1 and RBD2) separated by two zinc finger motifs. Although alternative splicing in the RBD1 of Rim is known to produce long and short forms of RBD (named Rim1 and Rim1Delta56-105, and Rim2(+40A) and Rim2, respectively), with the long form of Rim1 and short form of Rim2 being dominant in mouse brain, the physiological significance of the alternative splicing in RBD1 has never been elucidated. In the present study I discovered that alternative splicing in Rim RBD1 alters Rab3A binding affinity to Rims, and found that insertion of 40 amino acids into the RBD1 of Rim2 (i.e. Rim2(+40A)) dramatically reduced its Rab3A binding activity (more than a 50-fold decrease in affinity). Similarly, Rim1Delta56-105 exhibited higher affinity binding to Rab3A than the long form of Rim1. Expression of the short forms of the Rim RBD in PC12 cells co-localized well with endogenous Rab3A, whereas expression of the long forms of the Rim RBD in PC12 cells resulted in cytoplasimc and nuclear localization. Moreover, I found that Caenorhabditis elegans Rim/UNC-10 (ce-Rim) and Drosophila Rim (dm-Rim) do not interact with ce-Rab3 and dm-Rab3, respectively, indicating that the Rab3-effector function of Rim has not been retained during evolution. Based on these findings, I propose that the Rab3A-effector function of Rim during secretory vesicle exocytosis is limited to the short form of the mammalian Rim RBD alone.
巻・号 9(9)
ページ 831-42
公開日 2004-9-1
DOI 10.1111/j.1365-2443.2004.00767.x
PII GTC767
PMID 15330860
MeSH Alternative Splicing* Animals Binding Sites Biological Evolution* Caenorhabditis elegans Proteins / metabolism Carrier Proteins / metabolism Drosophila Proteins / genetics Drosophila Proteins / metabolism GTP-Binding Proteins / chemistry GTP-Binding Proteins / genetics* GTP-Binding Proteins / physiology Mice Molecular Sequence Data Nerve Tissue Proteins / chemistry Nerve Tissue Proteins / genetics* Nerve Tissue Proteins / physiology PC12 Cells Protein Structure, Secondary Protein Structure, Tertiary Rats Zinc Fingers rab3 GTP-Binding Proteins / chemistry rab3 GTP-Binding Proteins / genetics* rab3 GTP-Binding Proteins / metabolism* rab3A GTP-Binding Protein / analysis rab3A GTP-Binding Protein / metabolism*
IF 1.655
引用数 17
WOS 分野 GENETICS & HEREDITY CELL BIOLOGY
リソース情報
遺伝子材料 pEF-T7-mouse Rim2(+4A) (RDB15098) pEF-T7-mouse Rim2(+44A) (RDB15099) pEF-mouse FLAG-Munc13-1 (RDB15180).