Center of Excellence for Molecular Crop, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok 10330, Thailand.
Biosci Biotechnol Biochem. 2022 Aug 24;86(9):1211-1219. doi: 10.1093/bbb/zbac115.
Calmodulin, a primary calcium sensor in eukaryotes, binds calcium and regulates the activity of effector proteins in response to calcium signals that evoked in response to abiotic and biotic stress. To identify physiological responses associated with improved tolerance under dehydration stress that may be regulated by calmodulin in rice, the transgenic rice overexpressing OsCaM1-1, the control, and the wild-type KDML105 differing in their dehydration tolerance were compared 24 h after exposure to dehydration stress. The results demonstrated a greater increase in relative water content, relative growth rate, abscisic acid, photosynthetic pigment and proline contents, and antioxidant activities in the transgenic rice plants, whereas Na/K and Na/Ca ratio, lipid peroxidation, and electrolytic leakage decreased. The OsCaM1-1 gene overexpression in the transgenic rice showed greater tolerance to dehydration stress than non-transgenic rice, suggesting that OsCaM1-1 might play an important role in mitigating dehydration stress.
钙调素是真核生物中主要的钙传感器，它结合钙并调节效应蛋白的活性，以响应非生物和生物胁迫引起的钙信号。为了鉴定与提高耐旱性相关的生理反应，这些反应可能受水稻中的钙调蛋白调节，我们比较了在干旱胁迫下暴露 24 小时后，过表达 OsCaM1-1 的转基因水稻、对照和耐旱性不同的野生型 KDML105 的差异。结果表明，在转基因水稻中，相对水含量、相对生长率、脱落酸、光合色素和脯氨酸含量以及抗氧化活性均有较大增加，而 Na/K 和 Na/Ca 比值、脂质过氧化和电解质渗漏则减少。转基因水稻中 OsCaM1-1 基因的过表达比非转基因水稻表现出更强的耐旱性，表明 OsCaM1-1 可能在缓解干旱胁迫中发挥重要作用。
