细胞黏菌盘基网柄菌线粒体中大肠杆菌RecA的同源物。

A homolog of Escherichia coli RecA in mitochondria of the cellular slime mold Dictyostelium discoideum.

作者信息

Hasegawa Yasuna, Wakabayashi Masayuki, Nakamura Shogo, Kodaira Ken-ichi, Shinohara Hiroaki, Yasukawa Hiro

机构信息

Division of Bioengineering, Faculty of Engineering, Toyama University, Toyama 930-8555, Japan.

出版信息

DNA Repair (Amst). 2004 May 4;3(5):515-25. doi: 10.1016/j.dnarep.2004.01.014.

DOI:10.1016/j.dnarep.2004.01.014

PMID:15084313

Abstract

The cellular slime mold Dictyostelium discoideum expresses a gene encoding a 452-amino-acid polypeptide that is 47% identical to Escherichia coli RecA. A recA-deficient E. coli, JE6651, was transformed by pYSN1, which was designed to express the truncated form of the D. discoideum gene, and used in suppression assays. The viability of the transformant, JE6651(pYSN1), increased following UV irradiation or mitomycin C treatment. Phage lambda (red(-) gam(-)), which required RecA activity for DNA packaging, formed plaques on a lawn of JE6651(pYSN1). These results indicate that the gene product has a DNA recombination activity. Fluorescence of D. discoideum protein fused with GFP was detected in mitochondria. The gene disruption mutant was hypersensitive to UV-light (254nm), mitomycin C and H(2)O(2), indicating that D. discoideum recA is important for survival following exposure to DNA damaging agents.

摘要

细胞黏菌盘基网柄菌表达一种编码452个氨基酸多肽的基因，该多肽与大肠杆菌RecA的同源性为47%。用设计用于表达盘基网柄菌基因截短形式的pYSN1转化recA缺陷型大肠杆菌JE6651，并用于抑制试验。紫外线照射或丝裂霉素C处理后，转化体JE6651(pYSN1)的活力增加。需要RecA活性进行DNA包装的噬菌体λ(red(-)gam(-))在JE6651(pYSN1)菌苔上形成噬菌斑。这些结果表明该基因产物具有DNA重组活性。与绿色荧光蛋白融合的盘基网柄菌蛋白的荧光在线粒体中被检测到。基因敲除突变体对紫外线(254nm)、丝裂霉素C和H2O2高度敏感，表明盘基网柄菌recA在暴露于DNA损伤剂后对生存很重要。