The Dictyostelium discoideum family of Rho-related proteins
The Dictyostelium discoideum family of Rho-related proteins
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DOI：
10.1093/nar/29.5.1068
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发表时间：
2001-03-01
影响因子：
14.9
通讯作者：
Noegel, AA
中科院分区：
文献类型：
--
作者：
Rivero, F;Dislich, H;Noegel, AA
利用正在进行的盘基网柄菌基因组测序项目，我们在 15 个重叠群中组装了 >73kb 的基因组 DNA，其中包含 15 个基因和一个 Rho 相关蛋白的假基因。与 EST 序列的比较表明，每个基因都被至少 1 个、最多 4 个内含子打断。对于racC，已鉴定出广泛的选择性剪接。 Northern印迹分析表明，racA、racE、racG、racH和racl的mRNA存在于发育的所有阶段，而racJ和racL仅在晚期表达。氨基酸序列已在其他生物体的Rho相关蛋白的背景下进行了分析，Rac1a/1b/1c、RacF1/F2以及较小程度的RacB和RacA的GTPase结构域可以分组在Rac中亚科。其他盘基网柄菌 Rho 相关蛋白都不属于任何明确的亚家族，如 Rac、Cdc42 或 Rho，RacD 和 RacA 的独特之处在于它们缺乏 Rho 蛋白特有的异戊二烯化基序。 RacD：拥有 50 个残基 C 端延伸，RacA a：400 个残基 C 端延伸，其中包含：富含脯氨酸的区域、两个 BTB 结构域和一个新的 C 端结构域。我们还鉴定了果蝇和哺乳动物中 RacA 的同源物，从而定义了 Rho 蛋白的新亚家族 RhoBTB。
Taking advantage of the ongoing Dictyostelium genome sequencing project, we have assembled >73kb of genomic DNA in 15 contigs harbouring 15 genes and one pseudogene of Rho-related proteins, Comparison with EST sequences revealed that every gene is interrupted by at least one and up to four introns. For racC extensive alternative splicing was identified. Northern blot analysis showed that mRNAs for racA, racE, racG, racH and racl were present at all stages of development, whereas racJ and racL were expressed only at late stages, Amino acid sequences have been analysed in the context of Rho-related proteins of other organisms, Rac1a/1b/1c, RacF1/F2 and to a lesser extent RacB and the GTPase domain of RacA can be grouped in the Rac subfamily. None of the additional Dictyostelium Rho-related proteins belongs to any of the well-defined subfamilies, like Rac, Cdc42 or Rho, RacD and RacA are unique in that they lack the prenylation motif characteristic of Rho proteins. RacD: possesses a 50 residue C-terminal extension and RacA a: 400 residue C-terminal extension that contains: a proline-rich region, two BTB domains and a novel C-terminal domain. We have also identified homologues: for RacA in Drosophila and mammals, thus defining a new subfamily of Rho proteins, RhoBTB.