【目的】了解重要蛋白质的表达模式进而探讨水稻耐盐的分子机理。【方法】采用基于抗体的蛋白质组学策略,用免疫印迹(western blotting)调查了5个PP2Ac类磷酸酶蛋白质在苗期盐胁迫条件下的表达。【结果】发现在耐盐水稻品种兰胜中,OsPP2Ac-4的表达上调,在盐敏感的水稻品种9311中,OsPP2Ac-2、OsPP2Ac-3和OsPP2Ac-5的表达也发生了上调,但OsPP2Ac-4的表达下调。比较2个品种间PP2Ac蛋白质的表达,发现在正常生长条件下,PP2Ac蛋白质的表达没有显著区别且基本保持恒定,其表达变化仅发生在盐胁迫条件下。分析水稻MPSS数据库提供的苗期盐胁迫的转录数据,发现OsPP2Ac-2、OsPP2Ac-3和OsPP2Ac-5在盐胁迫条件下转录水平下调。【结论】发现了4个盐胁迫条件下表达发生变化的PP2Ac蛋白质。
【Objective】The protein expression profiling and the mechanism of rice salt-tolerance were studied.【Method】 The expression patterns of five rice phospatase 2A catalytic subunits(PP2Ac) in seedlings under salt-stressed conditions were surveyed by Western blotting via antibody-based proteomics strategy.【Result】 The results indicated that the expression of OsPP2Ac-4 protein was up-regulated in salt-tolerant rice variety Lansheng,and the expressions of OsPP2Ac-2,OsPP2Ac-3 and OsPP2Ac-5 were up-regulated in salt-sensitive rice variety 9311,while the expression of OsPP2Ac-4 was down-regulated in 9311.The expression of PP2Ac proteins was stable and in a similar level for Lansheng and 9311 under normal growth conditions,but the abundance variations were occurred only under salt-stressed conditions.Based on the Massively Parallel Signature Sequencing(MPSS) data derived from salt-stressed rice seedlings,it was found that the transcription of OsPP2Ac-2,OsPP2Ac-3 and OsPP2Ac-5 were down-regulated by comparison with control seedlings without salt treatment.【Conclusion】Four salt stress-related rice PP2Ac proteins were identified.