Chen Xu, Wang Yaofeng, Lv Bo, Li Jie, Luo Liqiong, Lu Songchong, Zhang Xuan, Ma Hong, Ming Feng
State Key Laboratory of Genetic Engineering, Institute of Genetics, Institute of Plant Biology, School of Life Science, Fudan University, Shanghai 200433, China.
Plant Cell Physiol. 2014 Mar;55(3):604-19. doi: 10.1093/pcp/pct204. Epub 2014 Jan 6.
Plants respond to environmental stresses by altering gene expression, and several genes have been found to mediate stress-induced expression, but many additional factors are yet to be identified. OsNAP is a member of the NAC transcription factor family; it is localized in the nucleus, and shows transcriptional activator activity in yeast. Analysis of the OsNAP transcript levels in rice showed that this gene was significantly induced by ABA and abiotic stresses, including high salinity, drought and low temperature. Rice plants overexpressing OsNAP did not show growth retardation, but showed a significantly reduced rate of water loss, enhanced tolerance to high salinity, drought and low temperature at the vegetative stage, and improved yield under drought stress at the flowering stage. Microarray analysis of transgenic plants overexpressing OsNAP revealed that many stress-related genes were up-regulated, including OsPP2C06/OsABI2, OsPP2C09, OsPP2C68 and OsSalT, and some genes coding for stress-related transcription factors (OsDREB1A, OsMYB2, OsAP37 and OsAP59). Our data suggest that OsNAP functions as a transcriptional activator that plays a role in mediating abiotic stress responses in rice.
植物通过改变基因表达来响应环境胁迫，已经发现多个基因介导胁迫诱导的表达，但还有许多其他因素有待确定。OsNAP是NAC转录因子家族的成员；它定位于细胞核，并在酵母中表现出转录激活活性。对水稻中OsNAP转录水平的分析表明，该基因受脱落酸（ABA）和非生物胁迫（包括高盐度、干旱和低温）的显著诱导。过表达OsNAP的水稻植株没有表现出生长迟缓，但水分流失率显著降低，在营养生长阶段对高盐度、干旱和低温的耐受性增强，并且在开花期干旱胁迫下产量提高。对过表达OsNAP的转基因植株进行微阵列分析发现，许多与胁迫相关的基因上调，包括OsPP2C06/OsABI2、OsPP2C09、OsPP2C68和OsSalT，以及一些编码与胁迫相关转录因子的基因（OsDREB1A、OsMYB2、OsAP37和OsAP59）。我们的数据表明，OsNAP作为转录激活因子，在介导水稻非生物胁迫响应中发挥作用。
