Characterization of Small Heat Shock Proteins Associated with Maize Tolerance to Combined Drought and Heat Stress
Characterization of Small Heat Shock Proteins Associated with Maize Tolerance to Combined Drought and Heat Stress
复制标题
与玉米对干旱和热应激的联合耐受性相关的小热激蛋白的表征
DOI：
10.1007/s00344-010-9157-9
复制
发表时间：
2010-12-01
影响因子：
4.8
通讯作者：
Lu, Minghui
中科院分区：
文献类型：
--
作者：
Hu, Xiuli;Li, Yanhui;Lu, Minghui
为了研究小热激蛋白（sHSPs）在调节玉米叶片应对干旱和热胁迫组合时的机制，采用蛋白质组学方法对遭受干旱和热胁迫组合的玉米植株的叶片蛋白质模式进行了监测。利用双向电泳（2 - DE）来鉴定玉米叶片中对干旱和热胁迫组合有响应的蛋白质斑点。考马斯亮蓝染色后，在每张凝胶上可重复检测到约450个蛋白质斑点，其中7个蛋白质斑点仅在热胁迫以及干旱和热胁迫组合下表达，而在对照和干旱条件下几乎未检测到。通过基质辅助激光解吸电离飞行时间质谱（MALDI - TOF MS），共鉴定出7种蛋白质，包括细胞色素b6 - f复合物铁硫亚基、sHSP17.4、sHSP17.2、sHSP26、鸟嘌呤核苷酸结合蛋白β亚基样蛋白、假定的未表征蛋白以及颗粒结合型淀粉合酶IIa。此外，在转录水平上分析了3种sHSPs的基因表达，结果表明这3种sHSPs在几种处理条件下均有表达，尽管它们在热胁迫以及干旱和热胁迫组合下的表达水平明显比在对照和干旱条件下更高。在研究脱落酸（ABA）对3种sHSPs的影响时，用100 μM ABA预处理在蛋白质水平上显著提高了3种sHSPs的表达，但在mRNA水平上仅有轻微提高。这些结果表明转录水平与翻译并不完全一致，并提示ABA诱导了sHSP17.2、sHSP17.4和sHSP26表达的转录后调控，这有助于更好地理解植物应对干旱和热胁迫组合的机制。
To investigate how the mechanisms of small heat shock proteins (sHSPs) in regulating maize leaves respond to the combination of drought and heat stress, leaf protein patterns were monitored using a proteomic approach in maize plants exposed to combined drought and heat stress. Two-dimensional electrophoresis (2-DE) was used to identify combined drought- and heat-responsive protein spots in maize leaves. After Coomassie brilliant blue staining, approximately 450 protein spots were reproducibly detected on each gel, wherein 7 protein spots were expressed only under heat and combined drought and heat stress but were almost undetected under control and drought. Using MALDI-TOF mass spectrometry, a total of seven proteins were identified, including cytochrome b6-f complex iron-sulfur subunit, sHSP17.4, sHSP17.2, sHSP26, guanine nucleotide-binding protein β-subunit-like protein, putative uncharacterized protein, and granule-bound starch synthase IIa. Moreover, the gene expression of three sHSPs was analyzed at the transcriptional level and indicated that all three sHSPs were expressed under several treatments although their expression levels were obviously more enhanced by heat and combined drought and heat stress than by control and drought. In investigations of the effect of abscisic acid (ABA) on the three sHSPs, pretreatment with 100 μM ABA enhanced substantially the expression of the three sHSPs at the protein level, but only slightly at the mRNA level. These results show that transcription levels are not completely concomitant with translation and suggest that ABA induces the post-transcriptional regulation of sHSP17.2, sHSP17.4, and sHSP26 expression, which can lead to a better understanding of the mechanisms of plant response to the combination of drought and heat stress.