Kahle Amber, Feng Yongmei, A Nelson Mark
Department of Pathology, Room 5208, Arizona Cancer Center, University of Arizona, 1501 N. Campbell Avenue, Tucson, AZ 85724, United States.
Gene. 2005 Jan 3;344:53-60. doi: 10.1016/j.gene.2004.10.020. Epub 2004 Dec 10.
CDK11 (cyclin-dependent kinase 11, formerly known as PITSLRE) is a member of the p34cdc2-related kinases. It has been previously shown to be involved in a variety of different cellular processes including RNA processing, apoptosis, and cell cycle progression. It is encoded by two different but highly similar genes, Cdc2L1 (cell division control 2 like 1) and Cdc2L2 (cell division control 2 like 2). Previous studies from our group identified and characterized the transcriptional regulation of the human Cdc2L2 gene promoter. The current studies identify and characterize the Cdc2L1 gene promoter. We cloned the promoter and elucidated the different transcriptional regulatory elements that reside within the 5' region of the gene. Deletion analysis of the promoter showed a region of nucleotides -152 to +11 to be necessary for basal transcription of the Cdc2L1 gene. Sequencing analysis found this region of the promoter to be highly GC-rich but is lacking both TATA and CAAT boxes. There are several different transcription factor binding sites that are consensus or near consensus found within this region. The potential binding sites include two Ets-1 sites, one Skn-1 site, and one E2F-1 site. Transfection studies of various site-directed mutagenesis clones for these different sites revealed that both Ets-1 sites play critical roles in sustained transcriptional activity as well as Skn-1. Chromatin immunoprecipitation of the endogenous promoter with Ets-1 and Skn-1 verified an in vivo association of Ets-1 and Skn-1 transcription factors with the endogenous promoter. These results, in addition to our Cdc2L2 results, lead to the further comprehension of the fundamental mechanisms dictating CDK11 gene expression through the Cdc2L1 gene promoter.
细胞周期蛋白依赖性激酶11（CDK11，以前称为PITSLRE）是与p34cdc2相关的激酶成员。先前已表明它参与多种不同的细胞过程，包括RNA加工、细胞凋亡和细胞周期进程。它由两个不同但高度相似的基因Cdc2L1（细胞分裂控制2样1）和Cdc2L2（细胞分裂控制2样2）编码。我们小组先前的研究鉴定并表征了人类Cdc2L2基因启动子的转录调控。当前的研究鉴定并表征了Cdc2L1基因启动子。我们克隆了启动子并阐明了位于该基因5'区域内的不同转录调控元件。启动子的缺失分析表明，核苷酸-152至+11区域对于Cdc2L1基因的基础转录是必需的。测序分析发现该启动子区域富含GC，但缺乏TATA盒和CAAT盒。在该区域内发现了几个不同的转录因子结合位点，这些位点是共有序列或接近共有序列。潜在的结合位点包括两个Ets-1位点、一个Skn-1位点和一个E2F-1位点。对这些不同位点的各种定点诱变克隆进行转染研究表明，两个Ets-1位点以及Skn-1位点在持续转录活性中都起着关键作用。用Ets-1和Skn-1对内源启动子进行染色质免疫沉淀，验证了Ets-1和Skn-1转录因子与内源启动子在体内的关联。这些结果，连同我们关于Cdc2L2的结果，使我们对通过Cdc2L1基因启动子决定CDK11基因表达的基本机制有了更深入的理解。
