Characterization of three cDNA species encoding plastid RNA polymerase sigma factors in Arabidopsis thaliana: evidence for the sigma factor heterogeneity in higher plant plastids

FEBS Letters

Nagatani, Akira¹  Takahashi, Hideo⁴  Tozawa, Yuzuru³  Mochizuki, Nobuyoshi¹  Wakasa, Kyo³  Tanaka, Kan⁴  Shinozaki, Kazuo² 

[1] Molecular Genetic Resarch Laboratory, Science Building 7, University of Tokyo, Hongo, Tokyo 113, Japan;Tsukuba Life Science Center, Institute of Physical and Chemical Research (RIKEN), 3-1-1 Koyadai, Tsukuba 305, Japan;National Agricultural Research Center, 3-1-1 Kannondai, Tsukuba 305, Japan;Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113, Japan

关键词: Expression sequence Tag;    Sigma factor;    Arabidopsis thaliana;    Plant plastid;    Gene expression;   

DOI  :  10.1016/S0014-5793(97)00906-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

By database search analysis, we identified three Arabidopsis EST (Expression Sequence Tag) entries having similarity to eubacterial RNA polymerase sigma factors. cDNA clones corresponding to these partial sequences were isolated, and the complete nucleotide sequences were determined. All three sequences encode proteins highly homologous to cyanobacterial and plastid sigma factors, and the gene products have N-terminal extensions which are assumed to function as plastid-targeting transit peptides. Thus we have concluded that the gene products are RNA polymerase sigma factors of plastids, and named sigA, sigB and sigC, respectively. Expression of these genes was analyzed by RNA gel-blot analysis and shown to be induced by illumination after a short-term dark adaptation. This strongly suggests that light regulation of the nuclear encoded sigma factor genes is involved in light-dependent activation of plastid promoters.

【 授权许可】

Unknown