Dovat S, Gilbert K A, Petrovic-Dovat L, Rannels D E
Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, C4723, 500 University Drive, Hershey, PA 17033, USA.
Biochim Biophys Acta. 1998 Nov 8;1442(2-3):380-8. doi: 10.1016/s0167-4781(98)00167-5.
Zinc-finger (ZF) proteins are widely distributed. The current study reports isolation, cloning and characterization of a novel ZF gene, RLZF-Y. Total RNA from rat lung was reverse transcribed. The 5' and 3' ends were isolated by rapid amplification of cDNA ends (RACE) using primers derived from a previously isolated partial clone. RACE products of 1.5 and 1.1 kb were cloned and sequenced. Identical overlapping sequence of 70 base pairs confirmed representation of the same cDNA approximately 2.5 kb in length. Probes derived from both 5' RACE and 3' RACE products independently hybridized to a 2.5 kb mRNA from rat lung. RLZF-Y mRNA is expressed in lung, brain, heart and kidney; expression is low in liver. Predicted amino acid sequence analysis defined three regions of similarity to known C2H2 ZF proteins: a region containing seven ZF structures characteristic of the Krüppel-like subfamily of ZF genes; a region with sequence similarity to the Krüppel-associated box A (KRAB-A) domain at the amino end; an amino-terminal leucine-rich region (LeR) adjacent to KRAB-A. The presence of KRAB-A and the adjacent LeR implies RLZF-Y protein may function as a transcriptional repressor.
锌指（ZF）蛋白分布广泛。当前研究报道了一种新型ZF基因RLZF - Y的分离、克隆及特性分析。从大鼠肺组织提取总RNA并进行逆转录。利用先前分离的部分克隆片段设计的引物，通过cDNA末端快速扩增（RACE）技术分离5'和3'末端。将1.5 kb和1.1 kb的RACE产物进行克隆和测序。70个碱基对的相同重叠序列证实了约2.5 kb长的同一cDNA的存在。来自5' RACE和3' RACE产物的探针分别与大鼠肺组织中的2.5 kb mRNA杂交。RLZF - Y mRNA在肺、脑、心脏和肾脏中表达；在肝脏中表达较低。预测的氨基酸序列分析确定了与已知C2H2锌指蛋白相似的三个区域：一个包含七个锌指结构的区域，这些结构是锌指基因Krüppel样亚家族的特征；一个在氨基末端与Krüppel相关盒A（KRAB - A）结构域具有序列相似性的区域；一个与KRAB - A相邻的富含亮氨酸的氨基末端区域（LeR）。KRAB - A和相邻LeR的存在表明RLZF - Y蛋白可能作为转录抑制因子发挥作用。
