Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, Taiwan.
Plant Signal Behav. 2010 Aug;5(8):1042-4. doi: 10.4161/psb.5.8.12404. Epub 2010 Aug 1.
In Arabidopsis thaliana, heat shock factor binding protein (AtHSBP) is a negative regulator of the heat shock response (HSR), and defective AtHSBP leads to seed abortion. We found that the wild-type and AtHSBP-knockout plants did not differ in ovule phenotypes at flower position 3, which indicates that the seed abortion occurs after fertilization and during embryogenesis. The conserved residues of the hydrophobic heptad repeat (HR) domains in AtHSBP were mutated and examined for their subcellular localization and interacting ability with heat shock factors (AtHSFs). The HR domains at the C terminus of AtHSBP are important for retaining AtHSBP in the cytoplasm under normal growth conditions and for interacting with AtHSFs, which negatively affects the DNA-binding capacity and transactivation activity of AtHSFs during the HSR.
在拟南芥中，热休克因子结合蛋白（AtHSBP）是热休克反应（HSR）的负调控因子，AtHSBP 缺陷会导致种子败育。我们发现，野生型和 AtHSBP 敲除植物在花 3 位的胚珠表型上没有差异，这表明种子败育发生在受精后和胚胎发生过程中。我们突变了 AtHSBP 保守的疏水性七肽重复（HR）结构域的残基，并检测了它们的亚细胞定位和与热休克因子（AtHSFs）的相互作用能力。AtHSBP C 端的 HR 结构域对于在正常生长条件下将 AtHSBP 保留在细胞质中以及与 AtHSFs 相互作用很重要，这会在 HSR 期间负调控 AtHSFs 的 DNA 结合能力和转录激活活性。
