两个水稻硝酸还原酶基因的克隆及其在不同环境刺激下的表达分析

Expression Analysis of Two NR Genes Responding to Various Environmental Factors

克隆并分析了水稻中两个可能的硝酸还原酶基因在多种非生物胁迫和重力刺激下的表达变化。AK102363(OsNR1)和AK102178(OsNR2)是水稻中两个可能的硝酸还原酶基因。在盐胁迫处理下,两基因均下调表达。OsNR1在100 mmol/L NaCl处理24 h时表达下调最显著,而OsNR2也是在100 mmol/L NaCl处理24 h时表达下调最显著。用15%PEG模拟干旱处理,两基因表达下调,24 h时差异最显著。低温处理24 h后,基因OsNR1同样下调表达。不同浓度的NO供体SNP处理,两基因均受诱导而上调表达,在0.1 mmol/L的SNP处理12 h时表达量最高。向重性刺激处理0.5 h后基因OsNR1在地上部基部下部分表达高于在地上部基部上部分的表达。在处理6 h时地上部基部上下两侧表达量的差异达到最大。

Two putative natrate reducases coding genes AK102363（OsNR1）and AK102178（OsNR2）in rice were cloned and further qRT-PCR assays were performed to profile their expression responding to various environmental stimuli.Our results showed that both of genes OsNR1 and OsNR2 were down regulated by the treatments of NaCl and 15% PEG which we used to mimic the salt and drought stresses and were down regulated significantly responding to low temperature.Both of two genes were able to be induced by SNP which was used as a NO releaser.They displayed an asymmetric expression in shoot base of rice after gravistimulation.The expression of OsNR1 and OsNR2 were up regulated in the lower half of rice shoot base,at 6 hours after gravistimulation more than six-fold increase in expression of OsNR1 and OsNR2 were observed in the lower half shoot base compared to the upper half shoot base.Our data provided here showed that the two genes related to the generation of NO in vivo were dynamically regulated by environment factors including abio-stresses and gravistimulation suggested an essential role of NO to enhance plant fitness to withstand a variety of environmental constraints like salt,drought,cold and gravity.