植物学报 ›› 2011, Vol. 46 ›› Issue (4): 379-385.DOI: 10.3724/SP.J.1259.2011.00379

• 研究报告 • 上一篇    下一篇

拟南芥GATL12基因影响叶绿体的形成

苏延萍1,2, 路小铎2,3, 沈颂东1, 张春义2,4*   

  1. 1苏州大学基础医学与生物科学学院, 苏州 215123;
    2中国农业科学院生物技术研究所, 北京 100081
    3中国科学院植物研究所信号转导与代谢组学研究中心, 北京 100093;
    4国家农作物基因资源与遗传改良重大科学工程, 北京 100081
  • 收稿日期:2011-03-09 修回日期:2011-04-13 出版日期:2011-07-01 发布日期:2011-07-01
  • 通讯作者: 张春义
  • 基金资助:

    国家自然科学基金

GATL12 is Essential for Chloroplast Biogenesis in Arabidopsis

Yanping Su1,2, Xiaoduo Lu2,3, Songdong Shen1, Chunyi Zhang2,4*   

  1. 1College of Basic Medicine and Biological Sciences, Soochow University, Suzhou 215123, China

    2Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China

    3Center of Metabolism and Signal Transduction, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China

    4 National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Beijing 100081, China
  • Received:2011-03-09 Revised:2011-04-13 Online:2011-07-01 Published:2011-07-01
  • Contact: Chunyi Zhang

摘要: 谷氨酰胺氨基转移酶(GATase)能够将谷氨酰胺上的氨基基团转移到底物上形成新的一碳氮基团。GATase有两种类型, 即Class-I (trpG型)和Class-II(purF型)。拟南芥(Arabidopsis thaliana)基因组中有13个基因编码Class-I类似蛋白(GATLs), 其生物学功能尚不清楚。首先分离到拟南芥GATL12基因的2个T-DNA插入突变体, 分别命名为gatl12-1gatl12-2。然后观察发现在这2个突变体的杂合植株中, 大部分植株的胚珠发育到第8天时, 由于叶绿体的积累而呈现绿色, 其余植株(约有25%)的胚珠为白色。将从杂合突变体植株上收获的种子播种在1/2MS培养基上, 有25%的幼苗发育成黄化苗。经PCR检测, 这些黄化苗为GATL12的纯合突变体, RT-PCR法在黄化苗中检测不到GATL12基因的转录本。电镜观察表明, 突变体中的叶绿体不能正常发育。上述结果表明, GATL12基因在拟南芥的叶绿体发育过程中具有重要作用。

Abstract: Glutamine amidotransferase (GATase) catalyses the removal of the ammonia group from glutamine and then transfers this group to a substrate to form a new carbon-nitrogen group. Two classes of GATase domains have been identified: Class I (also known as trpG-type or triad) and Class II (also known as purF-type or Ntn). Arabidopsis genome contains 13 genes encoding Class-I-like proteins (GATLs) and their biological functions have not been reported. We isolated two T-DNA insertion mutants of GATL12 (gatl12-1 and gatl12-2) in which most of the ovules in the heterozygous mutants turned green on day 8 due to the chloroplast accumulation, but about 25% of the ovules were white. About 25% of heterozygous plant seeds cultured in 1/2MS medium developed into albino seedlings, which were homozygous mutants demonstrated by PCR. The transcripts of GATL12 could not be detected in the albino seedlings. Electron microscopy analysis showed that the chloroplasts could not develop in the mutants. Our results suggest that GATL12 plays an important role in chloroplast development in Arabidopsis.