RRP42, a Subunit of Exosome, Plays an Important Role in Female Gametophytes Development and Mesophyll Cell Morphogenesis in Arabidopsis.
RRP42, a Subunit of Exosome, Plays an Important Role in Female Gametophytes Development and Mesophyll Cell Morphogenesis in Arabidopsis.
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RRP42 是外泌体的一个亚基，在拟南芥雌配子体发育和叶肉细胞形态发生中发挥重要作用
DOI：
10.3389/fpls.2017.00981
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发表时间：
2017
影响因子：
5.6
通讯作者：
Han Y
中科院分区：
文献类型：
--
作者：
Yan X;Yan Z;Han Y
外泌体复合物在RNA代谢中起着核心和必要的作用。然而，目前对植物外泌体亚基功能的研究还很有限。在这里，我们使用卵细胞特异性启动子控制的CRISPR/Cas9系统敲除编码拟南芥外泌体核心亚基的RRP42，并提供了RRP42对雌性配子体发育至关重要的证据。接下来，我们设计了三种不同的靶向RRP42的amirna。rrp42敲低突变体的叶片主要呈杂色和锯齿状，尤其是茎生叶片。茎生叶片的内部解剖结构显示出不规则形状的栅栏细胞和减少的叶肉细胞密度。有趣的是，我们在rrp42敲除突变体的生长后期检测到编码木葡聚糖内转葡萄糖基化酶/水解酶（XTHs）和扩张蛋白（EXPAs）的高积累mrna。对XTH19、EXPA10和EXPA11 mRNA的衰变动力学分析表明，RRP42参与了这些mRNA在细胞质中的衰变。RRP42定位于细胞核和细胞质中，在生长后期优先在茎叶中表达。总之，我们的研究结果表明，RRP42在雌性配子体的发育中是必不可少的，在叶肉细胞的形态发生中起重要作用。
The exosome complex plays a central and essential role in RNA metabolism. However, current research on functions of exosome subunit in plants is limited. Here, we used an egg cell-specific promoter-controlled CRISPR/Cas9 system to knock out RRP42 which encodes a core subunit of the Arabidopsis exosome and presented evidence that RRP42 is essential for the development of female gametophytes. Next, we designed three different amiRNAs targeting RRP42. The rrp42 knock-down mutants mainly displayed variegated and serrated leaves, especially in cauline leaves. The internal anatomy of cauline leaves displayed irregularly shaped palisade cells and a reduced density of mesophyll cells. Interestingly, we detected highly accumulated mRNAs that encode xyloglucan endotransglucosylase/hydrolases (XTHs) and expansins (EXPAs) during later growth stages in rrp42 knock-down mutants. The mRNA decay kinetics analysis for XTH19, EXPA10, and EXPA11 revealed that RRP42 had a role in the decay of these mRNAs in the cytoplasm. RRP42 is localized to both the nucleus and cytoplasm, and RRP42 is preferentially expressed in cauline leaves during later growth stages. Altogether, our results demonstrate that RRP42 is essential for the development of female gametophytes and plays an important role in mesophyll cell morphogenesis.