Wagner A C, Strowski M Z, Göke B, Williams J A
Department of Gastroenterology, Philipps University, Marburg, Germany.
Biochem Biophys Res Commun. 1995 Feb 27;207(3):950-6. doi: 10.1006/bbrc.1995.1277.
Members of the Rab family of low molecular weight GTP-binding (LMWG) proteins regulate vesicular transport; distinct Rab proteins are located in specific vesicular compartments within the exocytotic and endocytotic pathway. Pancreatic zymogen granules possess multiple LMWG. Rab 3A, however, which has been suggested to regulate exocytosis of synaptic vesicles, is not present in rat pancreatic acinar cells or on zymogen granules (BBRC 1994,269:542-548). To look for homologues of Rab 3A we have screened a rat pancreatic cDNA library using Rab 3A as a probe. We now report the cDNA and deduced amino acid sequence of a new member of the Rab protein family. Rab 26 is a 190 AA protein with a predicted molecular mass of 21,459 Dalton. It is expressed in pancreas, kidney, brain, submandibular gland, and lung. It is most closely related to Rab 8. There is also close homology to Rab 15, Sec4 and Rab 3.
低分子量GTP结合（LMWG）蛋白的Rab家族成员调节囊泡运输；不同的Rab蛋白位于胞吐和胞吞途径中的特定囊泡区室。胰腺酶原颗粒含有多种LMWG。然而，有人提出调节突触小泡胞吐作用的Rab 3A在大鼠胰腺腺泡细胞或酶原颗粒中不存在（《生物化学与生物物理研究通讯》1994年，269:542 - 548）。为了寻找Rab 3A的同源物，我们用Rab 3A作为探针筛选了大鼠胰腺cDNA文库。我们现在报告Rab蛋白家族一个新成员的cDNA及推导的氨基酸序列。Rab 26是一种由190个氨基酸组成的蛋白质，预测分子量为21459道尔顿。它在胰腺、肾脏、大脑、下颌下腺和肺中表达。它与Rab 8关系最为密切。与Rab 15、Sec4和Rab 3也有密切的同源性。
