Lee H, Xiong L, Ishitani M, Stevenson B, Zhu J K
Department of Plant Sciences, University of Arizona, Tucson 85721, USA.
Plant J. 1999 Feb;17(3):301-8. doi: 10.1046/j.1365-313x.1999.00375.x.
Low temperature is an important environmental factor influencing plant growth and development. In this study, we report the characterization of a genetic locus, HOS2, which is defined by three Arabidopsis thaliana mutants. The hos2-1, hos2-2 and hos2-3 mutations result in enhanced expression of RD29A and other stress genes under low temperature treatment. Gene expression in response to osmotic stress or ABA is not affected in the hos2 mutants. Genetic analysis indicates that the hos2 mutations are recessive and in a nuclear gene. Compared with the wild-type plants, the hos2-1 mutant plants are less capable of developing freezing tolerance when treated with low non-freezing temperatures. However, the hos2-1 mutation does not impair the vernalization response. These results indicate that HOS2 is a negative regulator of low temperature signal transduction important for plant cold acclimation.
低温是影响植物生长发育的一个重要环境因素。在本研究中，我们报道了一个由三个拟南芥突变体所定义的基因位点HOS2的特征。hos2-1、hos2-2和hos2-3突变导致低温处理下RD29A和其他胁迫基因的表达增强。hos2突变体中对渗透胁迫或脱落酸的基因表达不受影响。遗传分析表明，hos2突变是隐性的，位于一个核基因中。与野生型植物相比，hos2-1突变体植物在非冰冻低温处理时形成抗冻性的能力较弱。然而，hos2-1突变并不损害春化反应。这些结果表明，HOS2是植物冷驯化过程中低温信号转导的负调控因子。
