Nguyen Thomas B, Manova Katia, Capodieci Paola, Lindon Catherine, Bottega Steve, Wang Xiang-Yuan, Refik-Rogers Jale, Pines Jonathon, Wolgemuth Debra J, Koff Andrew
Department of Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10021, USA.
J Biol Chem. 2002 Nov 1;277(44):41960-9. doi: 10.1074/jbc.M203951200. Epub 2002 Aug 15.
We report the identification and expression pattern of a full-length human cDNA and a partial mouse cDNA encoding cyclin B3. Cyclin B3 (CCNB3) is conserved from Caenorhabditis elegans to Homo sapiens and has an undefined meiotic function in female, but not male Drosophila melanogaster. We show that H. sapiens cyclin B3 interacts with cdk2, is localized to the nucleus, and is degraded during anaphase entry after the degradation of cyclin B1. Degradation is dependent on sequences conserved in a destruction box motif. Overexpression of nondegradable cyclin B3 blocks the mitotic cell cycle in late anaphase, and at higher doses it can interfere with progression through G(1) and entry into S phase. H. sapiens cyclin B3 mRNA and protein are detected readily in developing germ cells in the human testis and not in any other tissue. The mouse cDNA has allowed us to further localize cyclin B3 mRNA to leptotene and zygotene spermatocytes. The expression pattern of mammalian cyclin B3 suggests that it may be important for events occurring in early meiotic prophase I.
我们报告了编码细胞周期蛋白B3的全长人类cDNA和部分小鼠cDNA的鉴定及表达模式。细胞周期蛋白B3（CCNB3）从秀丽隐杆线虫到智人均保守存在，在雌性黑腹果蝇中有未明确的减数分裂功能，而在雄性中则没有。我们发现人类细胞周期蛋白B3与细胞周期蛋白依赖性激酶2（cdk2）相互作用，定位于细胞核，并在细胞周期蛋白B1降解后的后期进入阶段被降解。降解依赖于破坏盒基序中保守的序列。不可降解的细胞周期蛋白B3的过表达在后期阻滞有丝分裂细胞周期，在更高剂量时它会干扰G1期进程并阻止进入S期。人类细胞周期蛋白B3的mRNA和蛋白质在人类睾丸发育中的生殖细胞中易于检测到，而在任何其他组织中均未检测到。小鼠cDNA使我们能够将细胞周期蛋白B3的mRNA进一步定位到细线期和偶线期精母细胞。哺乳动物细胞周期蛋白B3的表达模式表明它可能对减数分裂前期I早期发生的事件很重要。
