Krebber H, Ponstingl H
Division for Molecular Biology of Mitosis, German Cancer Research Center, Heidelberg, Germany.
Gene. 1996 Nov 21;180(1-2):7-11. doi: 10.1016/s0378-1119(96)00389-7.
RanGAP1 is the activator of the Ras-related nuclear GTPase Ran, which is involved in the nucleo-cytoplasmic transport of both, proteins and mRNAs, and also in cell cycle regulation. Here, we report a 2970-bp cDNA clone of RanGAP1 isolated from a HeLa lambda gt11 cDNA library. It contains a 215-bp 5' untranslated region (UTR) with a G + C-content of 68%, followed by a 1764-bp open reading frame and a 989-bp 3' UTR preceding a 77-bp poly(A)+ tail. RanGAP1 shows differential patterns of expression in human tissues. In addition to the 3.5-kb transcript present in all tissues and highly expressed in brain, thymus and testis, we found a second transcript of 2.8 kb in testis. In order to analyze this shorter transcript, we screened a human testis lambda gt10 cDNA library and cloned an alternatively polyadenylated RanGAP1 transcript. Taking the 3' UTR of RanGAP1, which lies downstream of the first polyadenylation signal, as a probe in Northern blot analysis, we confirmed that this second transcript found in testis results from a distinct 3' UTR.
RanGAP1是Ras相关核GTP酶Ran的激活剂，Ran参与蛋白质和mRNA的核质运输，也参与细胞周期调控。在此，我们报道了从HeLa λgt11 cDNA文库中分离得到的RanGAP1的一个2970 bp的cDNA克隆。它包含一个215 bp的5'非翻译区（UTR），G + C含量为68%，接着是一个1764 bp的开放阅读框和一个989 bp的3' UTR，在其前面有一个77 bp的聚腺苷酸（A）+尾巴。RanGAP1在人体组织中呈现出不同的表达模式。除了在所有组织中都存在且在脑、胸腺和睾丸中高表达的3.5 kb转录本外，我们在睾丸中还发现了一个2.8 kb的第二转录本。为了分析这个较短的转录本，我们筛选了一个人睾丸λgt10 cDNA文库，并克隆了一个选择性聚腺苷酸化的RanGAP1转录本。以位于第一个聚腺苷酸化信号下游的RanGAP1的3' UTR作为探针进行Northern印迹分析，我们证实了在睾丸中发现的这个第二转录本来自一个不同的3' UTR。
