拟南芥At3g28220基因抗寒功能初步分析

Analysis on Cold Tolerance of At3g28220 Gene in Arabidopsis

采用RT-PCR分析、基因克隆、转化等方法对At3g28220基因功能进行了研究。结果发现At3g28220基因在拟南芥受到低温及盐胁迫时才会在拟南芥中表达,且在不同生长期不同器官中的表达量无明显差异。通过构建35s:At3g28220基因正反向表达载体转化拟南芥,T1植株经卡那霉素抗性筛选,RT-PCR检测,结果表明At3g28220基因已经整合到拟南芥基因组中,并在转录水平表达。正常生长条件下,转基因拟南芥与野生型拟南芥的生长未见明显区别,而经过低温胁迫研究发现,正向表达转基因拟南芥的冷冻耐受能力明显高于野生型植株。说明拟南芥hos10-1冷驯化能力的丧失是与At3g28220基因的表达下调有直接的关系。

Arabidopsis mutant hos10-1（for high expression of osmotically responsive gene） have reported,in which completely loss the capability of cold acclimation and more rapidly activated than in wild-type by low temperature or salt stress（NaCl）.Microarray analysis revealed that At3g28220 genes with lower expression in the hos10-1 plant by 2-fold.In this study,RT-PCR,gene clone,transformation were used to study the function of At3g28220 gene in Arabidopsis.The result showed that At3g28220 gene can induced by cold acclimation and salt stress,the gene expression haven′t obviously distinction in different organs of Arabidopsis in different time.An At3g28220 ORF amplified by RT-PCR form Arabidopsis was norientation and inverted cloned into the downstream of 35S promoter of vector pCAMAIA2301.The construct was introduced in Arabidopsis through an Agrobacterium-mediated transformation.T1-generation plants screened by Kan resistance,confirmed by RT-PCR proved that At3g28220 gene had integrated into the Arabidopsis and expressed at the transcriptional level.In additon,we also found that transgenic plants had no significant growth inhibiton under normal growth condition.After a transient freezing treatment,transgenic plants had a significantly higher survival rate than of wild type plants.These results suggest that loss the capability of cold acclimation in mutant hos10-1 have the direct relation with the lower expression of the At3g28220 gene.