Kim Dongjin, Ntui Valentine Otang, Xiong Liming
Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
FEBS Lett. 2016 Jul;590(14):2201-9. doi: 10.1002/1873-3468.12234. Epub 2016 Jun 23.
Abscisic acid (ABA) is an important phytohormone that controls several plant processes such as seed germination, seedling growth, and abiotic stress response. Here, we report that AtYak1 plays an important role in ABA signaling and postgermination growth in Arabidopsis. AtYak1 knockout mutant plants were hyposensitive to ABA inhibition of seed germination, cotyledon greening, seedling growth, and stomatal movement. atyak1-1 mutant plants display reduced drought stress resistance, as evidenced by water loss rate and survival rate. Molecular genetic analysis revealed that AtYak1 deficiency led to elevated expression of stomatal-related gene, MYB60, and down-regulation of several stress-responsive genes. Altogether, these results indicate that AtYak1 plays a role as a positive regulator in ABA-mediated drought response in Arabidopsis.
脱落酸（ABA）是一种重要的植物激素，它控制着多种植物生理过程，如种子萌发、幼苗生长和非生物胁迫响应。在此，我们报道AtYak1在拟南芥的ABA信号传导和萌发后生长中发挥重要作用。AtYak1基因敲除突变体植株对ABA抑制种子萌发、子叶绿化、幼苗生长和气孔运动表现出低敏感性。atyak1-1突变体植株表现出抗旱性降低，这通过失水率和存活率得以证明。分子遗传学分析表明，AtYak1缺失导致气孔相关基因MYB60的表达升高，以及几个胁迫响应基因的下调。总之，这些结果表明AtYak1在拟南芥ABA介导的干旱响应中作为正向调节因子发挥作用。
