青稞根质膜水通道蛋白基因对冷胁迫的响应

The Response of RootHvPIPs to Chilling Stress in Tibetan Hulless Barley Seedling

为深入研究青稞冷胁迫引发水分生理变化的分子机理,以青海青稞主栽品种肚里黄为材料,采用荧光定量PCR(qRT-PCR)技术对根水通道蛋白PIPs基因在冷胁迫下的表达模式进行分析,同时对根的水导度(Lpr)和叶片净光合速率(Pn)进行测定。结果表明,青稞幼苗冷胁迫后主要影响了苗的生长速率,Lpr和Pn均表现为胁迫期下降、恢复期上升,但Lpr的变化差异不显著,而Pn的变化达到显著标准。冷胁迫后HvPIPs基因表达量总体下降,温度恢复后大多数Hv PIPs基因仍然保持下降趋势,但Hv PIP1;1基因和Hv PIP1;2基因的表达量变化略有区别。因此,可推测青稞由于其高抗寒性而导致HvPIPs在抗冷反应中的响应有其特殊之处。

The aim of this study is to reveal the response characteristics of plasma membrane aquaporin （plasma membrane intrinsic proteins,PiPs） genes under chilling stress in Tibetan hulless barley. In this study, Dulihuang, a Qinghai Tibetan hulless barley cultivar, was used to investigate the expression of PIPs in root under 4℃ chilling stress with quantitative real-time reverse transcriptase PCR （qRT- PCR） ,the hydraulic conductivity （Lpr） of root and net photosynthetic rate （Pn） of leaf were also in- vestigated at the same time. The results showed that the growth of Tibetan hulless barley seedlings was significantly inhibited under 4 ~C stress. Lpr and Pn were decreased under chilling stress and in- creased as the chilling stress was removed,the difference in Lpr was not significant,but in Pn was sig- nificant. The results of qRT-PCR showed the expression levels of HvPIPs were decreased overall after cold treatment and the expression levels of most HvPIPs were decreasing continuously in recovery pe- riod. But the expression patterns of HvPIP1;1 and HvPIP 1;2 were different. It can be inferred that the specific response of HvPIPs in Tibetan hulless barley under chilling stress is the cause of its high cold resistance.