Plant Biology Institute, Biological Research Centre, Hungarian Academy of Sciences, 6726 Szeged, Hungary.
Doctoral School in Biology, Faculty of Science and Informatics, University of Szeged, 6720 Szeged, Hungary.
Int J Mol Sci. 2018 Apr 25;19(5):1282. doi: 10.3390/ijms19051282.
The Calcium-Dependent Protein Kinase (CDPK)-Related Kinase family (CRKs) consists of eight members in . Recently, At was shown to play a direct role in the regulation of root gravitropic response involving polar auxin transport (PAT). However, limited information is available about the function of the other At genes. Here, we report a comparative analysis of the CRK genes, including transcription regulation, intracellular localization, and biological function. At transcripts were detectable in all organs tested and a considerable variation in transcript levels was detected among them. Most AtCRK proteins localized at the plasma membrane as revealed by microscopic analysis of 35S::cCRK-GFP (Green Fluorescence Protein) expressing plants or protoplasts. Interestingly, 35S::cCRK1-GFP and 35S::cCRK7-GFP had a dual localization pattern which was associated with plasma membrane and endomembrane structures, as well. Analysis of T-DNA insertion mutants revealed that At genes are important for root growth and control of gravitropic responses in roots and hypocotyls. While At mutants were indistinguishable from wild type plants in short days, At mutant had serious growth defects under continuous illumination. Semi-dwarf phenotype of At was accompanied with chlorophyll depletion, disturbed photosynthesis, accumulation of singlet oxygen, and enhanced cell death in photosynthetic tissues. At is therefore important to maintain cellular homeostasis during continuous illumination.
钙依赖蛋白激酶（CDPK）相关激酶家族（CRKs）在 中由八个成员组成。最近，At 被证明在涉及极性生长素运输（PAT）的根向地性反应的调节中起直接作用。然而，关于其他 At 基因的功能，信息有限。在这里，我们报告了对 CRK 基因的比较分析，包括转录调控、细胞内定位和生物学功能。在所有测试的器官中都可以检测到 At 转录本，并且它们之间的转录水平存在相当大的差异。通过对 35S::cCRK-GFP（绿色荧光蛋白）表达植物或原生质体的显微镜分析，大多数 AtCRK 蛋白定位于质膜上。有趣的是，35S::cCRK1-GFP 和 35S::cCRK7-GFP 具有与质膜和内膜结构相关的双重定位模式。T-DNA 插入突变体的分析表明，At 基因对于根生长和根和下胚轴中向地性反应的控制很重要。虽然 At 突变体在短日照下与野生型植物无法区分，但 At 突变体在连续光照下生长缺陷严重。At 的半矮化表型伴随着叶绿素耗竭、光合作用紊乱、单线态氧积累和光合组织中的细胞死亡增加。因此，At 在连续光照下对于维持细胞内稳态很重要。
