School of Resources and Environmental Sciences, Henan Institute of Science and Technology, Xinxiang, 453003, China.
School of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, Xinxiang, 453003, China.
Biochem Genet. 2021 Feb;59(1):256-282. doi: 10.1007/s10528-020-10004-z. Epub 2020 Sep 29.
Potassium (K) transport and channel systems play vital roles in plant growth, development and responses to various stresses. In this study, 44 putative K-transport-related genes (18K uptake permease (KUP)/high-affinity K (HAK)/K transporter (KT) family genes and 26 channel genes, including 18 Shaker family genes and 8K channel outward (KCO) family genes) were identified in the genome of Chinese cabbage (Brassica rapa ssp. pekinensis). To clarify the molecular evolution of each family in Chinese cabbage, phylogenetic analysis and assessments of the gene structures, conserved motifs, chromosomal locations, gene duplications, expression patterns and cis-acting elements of the 44 putative K-transport-related genes were performed. The phylogenetic analysis showed that these genes could be classified into five clades [KUP/HAK/KTs, KCOs, K, K (KAT) and K (AKT)] and that the members of a given clade shared conserved exon-intron distributions and motif compositions. These K-transport-related genes were unevenly distributed over all ten chromosomes, including four duplicated gene pairs that implied an expansion of K-transport-related genes in Chinese cabbage. Analyses of Illumina RNA-seq data for these 44K-transport-related genes indicated tissue-/organ-specific expression patterns. In addition, an overall evaluation showed that the expression levels of KUP/HAK/KT genes were significantly higher than those of potassium channel genes in six tissues. Promoter cis-acting element analysis revealed that these 44K-transport-related genes may be associated with responses to 10 abiotic stresses, primarily light, methyl jasmonate (MeJA) and abscisic acid (ABA). Our results provide a systematic and comprehensive overview of K-transport-related gene families in Chinese cabbage and establish a foundation for further research on K absorption and transport functions.
钾（K）转运和通道系统在植物生长、发育和对各种胁迫的响应中起着至关重要的作用。在本研究中，在白菜（Brassica rapa ssp. pekinensis）基因组中鉴定了 44 个假定的 K 转运相关基因（18 个 K 摄取渗透酶（KUP）/高亲和力 K（HAK）/K 转运体（KT）家族基因和 26 个通道基因，包括 18 个 Shaker 家族基因和 8 个 K 通道外向（KCO）家族基因）。为了阐明白菜中每个家族的分子进化，对 44 个假定的 K 转运相关基因的系统发育分析以及基因结构、保守基序、染色体定位、基因复制、表达模式和顺式作用元件进行了评估。系统发育分析表明，这些基因可以分为五个分支[KUP/HAK/KTs、KCOs、K、K（KAT）和 K（AKT）]，并且给定分支的成员共享保守的外显子-内含子分布和基序组成。这些 K 转运相关基因在所有十个染色体上不均匀分布，包括四个重复基因对，暗示了白菜中 K 转运相关基因的扩张。对这些 44 个 K 转运相关基因的 Illumina RNA-seq 数据进行分析表明，它们具有组织/器官特异性表达模式。此外，总体评估表明，在六个组织中，KUP/HAK/KT 基因的表达水平明显高于钾通道基因。启动子顺式作用元件分析表明，这些 44 个 K 转运相关基因可能与 10 种非生物胁迫的响应有关，主要是光、茉莉酸甲酯（MeJA）和脱落酸（ABA）。我们的研究结果为白菜 K 转运相关基因家族提供了系统和全面的概述，并为进一步研究 K 吸收和转运功能奠定了基础。
