Arabidopsis KHZ1 and KHZ2, two novel non-tandem CCCH zinc-finger and K-homolog domain proteins, have redundant roles in the regulation of flowering and senescence
Arabidopsis KHZ1 and KHZ2, two novel non-tandem CCCH zinc-finger and K-homolog domain proteins, have redundant roles in the regulation of flowering and senescence
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DOI：
10.1007/s11103-017-0667-8
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发表时间：
2017-12-01
影响因子：
5.1
通讯作者：
Han, Yuzhen
中科院分区：
文献类型：
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作者：
Yan, Zongyun;Jia, Jianheng;Han, Yuzhen
CCCH锌指和K同源蛋白（KHZ 1和KHZ 2）在拟南芥中具有重要的开花和衰老调控功能，在植物的发育和逆境应答中起重要作用。然而，许多CCCH锌指蛋白和KH蛋白的生物学功能仍然是未知的。KHZ 1和KHZ 2是拟南芥中两个新的CCCH锌指蛋白和KH结构域蛋白，属于CCCH家族的VII亚家族。我们获得了khz 1、khz 2突变体和khz 1 khz 2双突变体，以及KHZ 1和KHZ 2的过表达（OE）系。与野生型（WT）相比，khz2突变体在生长发育上没有缺陷，khz1突变体开花稍晚，而khz1 khz2双突变体表现出明显的晚花表型。相反，人工过表达KHZ 1和KHZ 2导致开花提前。与晚开花表型一致，开花抑制基因FLC在khz 1 khz 2中表达上调，而开花整合子和花分生组织特性（FMI）基因表达显著下调。此外，我们还观察到，KHZ 1和KHZ 2的OE植株叶片衰老明显提前，而khz 1和khz 2的双突变体叶片和植株衰老延迟。KHZ 1和KHZ 2在整个拟南芥组织中普遍表达。KHZ 1和KHZ 2定位于细胞核，具有转录激活活性和RNA结合能力。综上所述，我们得出结论，KHZ 1和KHZ 2在拟南芥开花和衰老的调控中具有冗余的作用。
The two novel CCCH zinc-finger and K-homolog (KH) proteins, KHZ1 and KHZ2, play important roles in regulating flowering and senescence redundantly in Arabidopsis.The CCCH zinc-finger proteins and K-homolog (KH) proteins play important roles in plant development and stress responses. However, the biological functions of many CCCH zinc-finger proteins and KH proteins remain uncharacterized. In Arabidopsis, KHZ1 and KHZ2 are characterized as two novel CCCH zinc-finger and KH domain proteins which belong to subfamily VII in CCCH family. We obtained khz1, khz2 mutants and khz1 khz2 double mutants, as well as overexpression (OE) lines of KHZ1 and KHZ2. Compared with the wild type (WT), the khz2 mutants displayed no defects in growth and development, and the khz1 mutants were slightly late flowering, whereas the khz1 khz2 double mutants showed a pronounced late flowering phenotype. In contrast, artificially overexpressing KHZ1 and KHZ2 led to the early flowering. Consistent with the late flowering phenotype, the expression of flowering repressor gene FLC was up-regulated, while the expression of flowering integrator and floral meristem identity (FMI) genes were down-regulated significantly in khz1 khz2. In addition, we also observed that the OE plants of KHZ1 and KHZ2 showed early leaf senescence significantly, whereas the khz1 khz2 double mutants showed delayed senescence of leaf and the whole plant. Both KHZ1 and KHZ2 were ubiquitously expressed throughout the tissues of Arabidopsis. KHZ1 and KHZ2 were localized to the nucleus, and possessed both transactivation activities and RNA-binding abilities. Taken together, we conclude that KHZ1 and KHZ2 have redundant roles in the regulation of flowering and senescence in Arabidopsis.