Moritani Kosho, Tagashira Hideki, Shimotori Taishin, Sakamoto Naoaki, Tanaka Shin, Takata Kazuko, Mitsunaga-Nakatsubo Keiko, Bojiiwa Yuto, Yamamoto Takashi, Shimada Hiraku, Akasaka Koji
Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.
Dev Growth Differ. 2004 Aug;46(4):335-41. doi: 10.1111/j.1440-169x.2004.00750.x.
We report the identification and characterization of Unichrom, a gene encoding a new G-stretch-DNA-binding protein in the sea urchin embryo. The derived amino acid sequence of Unichrom contains plant homeodomain (PHD) finger and high mobility group (HMG) motifs as well as motifs required for cell-cycle-dependent degradation. The expression of a Unichrom-green fluorescent protein (GFP) fusion protein in sea urchin embryonic cells indicates that Unichrom protein accumulates in nuclei during interphase and disperses into the cytoplasm at mitosis. Overexpression of dominant negative Unichrom, which contains the DNA binding domain lacking the motif for cell-cycle-dependent degradation, causes impairment of chromosome segregation. These results suggest that Unichrom binds to genome DNA at G-stretch and that degradation of Unichrom is required for segregation of chromosomes.
我们报告了对Unichrom的鉴定和表征，Unichrom是一种在海胆胚胎中编码新型G-链DNA结合蛋白的基因。Unichrom推导的氨基酸序列包含植物同源结构域（PHD）指状结构和高迁移率族（HMG）基序以及细胞周期依赖性降解所需的基序。Unichrom-绿色荧光蛋白（GFP）融合蛋白在海胆胚胎细胞中的表达表明，Unichrom蛋白在间期积累于细胞核中，并在有丝分裂时分散到细胞质中。显性负性Unichrom（其包含缺乏细胞周期依赖性降解基序的DNA结合结构域）的过表达会导致染色体分离受损。这些结果表明，Unichrom在G-链处与基因组DNA结合，并且Unichrom的降解是染色体分离所必需的。
