Dauda Wadzani Palnam, Shanmugam Veerubommu, Tyagi Aditya, Solanke Amolkumar U, Kumar Vishesh, Krishnan Subbaiyan Gopala, Bashyal Bishnu Maya, Aggarwal Rashmi
ICAR-Indian Agricultural Research Institute, New Delhi 110012, India.
Crop Science Unit, Department of Agronomy, Federal University, Gashua 1005, Nigeria.
Plants (Basel). 2022 Mar 29;11(7):917. doi: 10.3390/plants11070917.
Cytokinin glucosyltransferases (CGTs) are key enzymes of plants for regulating the level and function of cytokinins. In a genomic identification of rice CGTs, 41 genes with the plant secondary product glycosyltransferases (PSPG) motif of 44-amino-acid consensus sequence characteristic of plant uridine diphosphate (UDP)-glycosyltransferases (UGTs) were identified. In-silico physicochemical characterisation revealed that, though the CGTs belong to the same subfamily, they display varying molecular weights, ranging from 19.6 kDa to 59.7 kDa. The proteins were primarily acidic (87.8%) and hydrophilic (58.6%) and were observed to be distributed in the plastids (16), plasma membrane (13), mitochondria (5), and cytosol (4). Phylogenetic analysis of the CGTs revealed that their evolutionary relatedness ranged from 70-100%, and they aligned themselves into two major clusters. In a comprehensive analysis of the available transcriptomics data of rice samples representing different growth stages only the CGT, was significantly expressed at the vegetative stage, whereas 16 other genes were highly expressed only at the reproductive growth stage. On the contrary, six genes, and were significantly upregulated in rice plants inoculated with (RS), Xoo ( pv. ) and Mor (). In a qRT-PCR analysis of rice sheath tissue susceptible to , Mor, and Xoo pathogens, compared to the sterile distilled water control, at 24 h post-infection only two genes displayed significant upregulation in response to all the three pathogens: and . On the other hand, the expression of genes , and were observed to be pathogen-specific. These genes were identified as the candidate-responsive CGT genes and could serve as potential susceptibility genes for facilitating pathogen infection.
细胞分裂素糖基转移酶（CGTs）是植物中调节细胞分裂素水平和功能的关键酶。在对水稻CGTs进行的基因组鉴定中，鉴定出41个具有植物次生产物糖基转移酶（PSPG）基序的基因，该基序具有44个氨基酸的共有序列，是植物尿苷二磷酸（UDP）-糖基转移酶（UGTs）的特征。电子理化特性分析表明，尽管CGTs属于同一亚家族，但它们的分子量各不相同，范围从19.6 kDa到59.7 kDa。这些蛋白质主要呈酸性（87.8%）且亲水性强（58.6%），并观察到分布在质体（16个）、质膜（13个）、线粒体（5个）和胞质溶胶（4个）中。对CGTs的系统发育分析表明，它们的进化相关性在70%-100%之间，并分为两个主要簇。在对代表不同生长阶段的水稻样本的现有转录组数据进行的综合分析中，只有CGT在营养阶段显著表达，而其他16个基因仅在生殖生长阶段高表达。相反，六个基因，和在接种了RS、Xoo（稻瘟病菌）和Mor（稻曲病菌）的水稻植株中显著上调。在对易受RS、Mor和Xoo病原体感染的水稻叶鞘组织进行的qRT-PCR分析中，与无菌蒸馏水对照相比，在感染后24小时，只有两个基因对所有三种病原体均表现出显著上调：和。另一方面，观察到基因、和的表达具有病原体特异性。这些基因被鉴定为候选响应性CGT基因，可作为促进病原体感染的潜在易感性基因。
