多聚胞嘧啶结合蛋白结构与功能研究进展

Research progress in the structure and function of poly(c)-binding proteins

Poly(c)-结合蛋白[Poly(c)-binding proteins,PCBPs]是RNA结合蛋白的重要分支,包含与核不均一蛋白hnRNP K同源的KH(the K homology domain)结构域,该结构域可识别并结合RNA。以PCBP1为例,它的KH结构域内,KH1与KH2之间的连接区均存在相对集中的纯化选择位点。PCBP能够在转录水平调控多种基因的表达并调控mRNA的稳定性,如对遗传性乳腺卵巢癌易感基因brca1(breast cancer 1,early onset)、细胞周期依赖性激酶抑制因子p21等的调控。近年来,PCBP作为铁的分子伴侣,与铁蛋白(Ferritin)、二价金属转运因子(DMT1)、铁转运蛋白(Ferroportin)、脱氧辅蛋白羟化酶(Deoxyhypusine hydroxylase,DOHH)相互作用,参与细胞内铁代谢成为研究热点。对PCBP调节多个基因转录、mRNA稳定性及在铁代谢中的最新研究进展进行综述。

Poly（ c）-binding proteins （ PCBPs） is an important branch of RNA binding proteins, containing the homologous hnRNP K KH domain （ the K homology domain） which can recognize and bind RNA.Taking PCBP1 as an example, the purifing selection site of amino acids exist in three KH domains and the linker motif between KH1 and KH2.PCBPs play important roles in gene expression reg-ulation on the transcriptional and translational level that are involved in breast cancer genes like brca1 （ breast cancer 1, early onset） , it can also stabilize mRNA of several genes like p21.In recent years, as an iron molecular chaperone, PCBP has been reported to in-teract with ferritin, DMT1, ferriportin, deoxyhypusine hydroxylase （DOHH） and participate in cellular iron delivery.This article re-views the progress in the function of PCBPs in transcriptional regulation, mRNA stabilization and iron delivery.