Comparative Expression and Phylogenetic Analysis of Maize Cytokinin Dehydrogenase/Oxidase (CKX) Gene Family
Comparative Expression and Phylogenetic Analysis of Maize Cytokinin Dehydrogenase/Oxidase (CKX) Gene Family
复制标题
玉米细胞分裂素脱氢酶/氧化酶（CKX）基因家族的比较表达和系统发育分析
DOI：
10.1007/s00344-010-9155-y
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发表时间：
2010-12-01
影响因子：
4.8
通讯作者：
Yuan, Lixing
中科院分区：
文献类型：
--
作者：
Gu, Riliang;Fu, Junjie;Yuan, Lixing
细胞分裂素脱氢酶（CKX）降解植物中的细胞分裂素激素，并在细胞分裂素调节过程中发挥重要作用。 CKX 蛋白由具有不同数量成员的多基因家族编码。在本研究中，收集了13个玉米CKX序列，其中10个转录本经RT-PCR证实。组织和细胞分裂素依赖性表达研究表明ZmCKX基因表现出多种表达模式，表明其具有多种功能。除了13个玉米CKX之外，还使用7个拟南芥、9个杨树和11个水稻CKX蛋白构建系统发育树。 CKX 成员被分配到六组，内含子/外显子结构、序列基序和蛋白质特性在组内是保守的。 CKX 的基因组分布支持片段重复有助于 CKX 基因家族的扩展。通过对玉米成员的定量RT-PCR分析以及对拟南芥、杨树和水稻成员的组织表达模式进行数字Northern分析，发现一些直向同源物之间CKX基因的表达谱高度相关，而一些旁系同源物之间发现不同的表达方式。这些结果表明CKX家族各组内的功能保守性，并为基因功能从一个物种转移到另一个物种提供了线索，并进一步有助于揭示CKX基因在植物中的作用。
Cytokinin dehydrogenase (CKX) degrades the cytokinin hormone in plants and plays an important role in cytokinin regulatory processes. CKX proteins are encoded by a multigene family with a varying number of members. In this study, 13 maizeCKXsequences were collected in which ten transcripts were confirmed by RT-PCR. The tissue- and cytokinin-dependent expression studies indicated thatZmCKXgenes exhibit a variety of expression patterns, suggesting diverse functions. Besides 13 maize CKXs, 7Arabidopsis, 9 poplar, and 11 rice CKX proteins were further used to construct a phylogenetic tree. The CKX members were assigned to six groups, and the intron/exon structures, sequence motifs, and protein properties were conserved within groups. The genome distribution ofCKXssupports that segmental duplication contributes to the expansion of theCKXgene family. By quantitative RT–PCR analysis of maize members and digital Northern analysis ofArabidopsis, poplar, and rice members for their tissue expression patterns, highly correlative expression profiles ofCKXgenes were found among some of the orthologs, whereas different expression manners were found between some of the paralogs. These results suggest functional conservation within each group of the CKX family and provide a clue for transfer of a gene function from one species to the other and further contribute to uncovering the role ofCKXgenesin planta.