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为了进一步阐明与小麦生长期热胁迫有关的面团强度损失的分子机理，研究了热激蛋白（ＨＳＰ）的作用和麦谷蛋白基因上游的热激因子。不同的基因型在热胁迫过程中高分子量麦谷蛋白亚基（ＨＭＷ—ＧＳ）和ＨＳＰ的合成情况不同。小麦植株经过几天的热胁迫，致使其成熟种子中存留的ＨＳＰ７０的浓度增加。４５个基因型的热胁迫植株样品的成熟种子ＨＳＰ７０的含量与面团强度损失不相关。这种机理的证据远不如其它分子假说，特别是麦谷蛋白／醇溶蛋白比例的变化，将从受热胁迫的种子中提纯得到的ＨＳＰ７０加到面团中，２ｇ面粉中加入２ｍｇ时，ＨＳＰ特性类似于其它水合蛋白，即使ＨＳＰ加入量已超过成熟种子在田间所能达到的最大水平，对面团特性也没有很大影响。此外，甚至在对热胁迫反应变化很大的基因型中，对ＨＭＷ—ＧＳ基因（编码区上游）测序也没有发现热激启动子。这些结果排除了面团强度损失与热有关的可能性，将注意力集中在麦谷蛋白链聚合程度和种子发育过程中ＨＳＰ及其伴随物的作用上。
In order to further elucidate the molecular mechanism of the loss of dough strength associated with heat stress during wheat growth, the role of heat shock protein (HSP) and the heat shock factor upstream of glutenin gene were studied. Different genotypes differed in the synthesis of high molecular weight glutenin subunit (HMW-GS) and HSP during heat stress. After several days of heat stress in wheat plants, the concentration of HSP70 remaining in its mature seeds is increased. The content of mature seeds HSP70 in 45 genotypes of heat stressing plant samples was not related to the dough strength loss. The evidence for this mechanism is far less than the other molecular hypotheses, notably the changes in the glutenin / gliadin ratio, adding HSP70 purified from heat-stressed seeds to the dough and adding 2 mg to 2 g of flour, the HSP profile is similar to Other hydrated proteins, even if added in amounts that exceed the maximum levels of mature seeds in the field, do not have a significant impact on the dough properties. In addition, no heat shock promoter was found in the sequencing of the HMW-GS gene (upstream of the coding region) even in genotypes that had a dramatic change in response to heat stress. These results rule out the possibility of heat-related loss of dough strength and focus on the degree of gluten chain polymerization and the role of HSPs and their congeners during seed development.