玉米 Dek51 编码一个 DEAD-box RNA 解旋酶，对于前 rRNA 加工和种子发育是必需的。

Maize Dek51 encodes a DEAD-box RNA helicase essential for pre-rRNA processing and seed development.

机构信息

Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao 266237, China.

National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, Zhengzhou 450002, China.

出版信息

Cell Rep. 2024 Sep 24;43(9):114673. doi: 10.1016/j.celrep.2024.114673. Epub 2024 Aug 27.

DOI:10.1016/j.celrep.2024.114673

PMID:39196780

Abstract

Pre-rRNA processing is essential to ribosome biosynthesis. However, the processing mechanism is not fully understood in plants. Here, we report a DEAD-box RNA helicase DEK51 that mediates the 3' end processing of 18S and 5.8S pre-rRNA in maize (Zea mays L.). DEK51 is localized in the nucleolus, and loss of DEK51 arrests maize seed development and blocks the 3' end processing of 18S and 5.8S pre-rRNA. DEK51 interacts with putative key factors in nuclear RNA exosome-mediated pre-rRNA processing, including ZmMTR4, ZmSMO4, ZmRRP44A, and ZmRRP6L2. This suggests that DEK51 facilitates pre-rRNA processing by interacting with the exosome. Loss of ZmMTR4 function arrests seed development and blocks the 3' end processing of 18S and 5.8S pre-rRNA, similar to dek51. DEK51 also interacts with endonucleases ZmUTP24 and ZmRCL1, suggesting that it may also be involved in the cleavage at site A2. These results show the critical role of DEK51 in promoting 3' end processing of pre-rRNA.

摘要

前 rRNA 加工对于核糖体生物合成至关重要。然而，植物中的加工机制还不完全清楚。在这里，我们报道了一种 DEAD-box RNA 解旋酶 DEK51，它介导玉米（Zea mays L.）中 18S 和 5.8S 前 rRNA 的 3'端加工。DEK51 定位于核仁中，缺失 DEK51 会导致玉米种子发育停滞，并阻止 18S 和 5.8S 前 rRNA 的 3'端加工。DEK51 与核 RNA 外切体介导的前 rRNA 加工中的假定关键因子相互作用，包括 ZmMTR4、ZmSMO4、ZmRRP44A 和 ZmRRP6L2。这表明 DEK51 通过与外切体相互作用促进前 rRNA 加工。ZmMTR4 功能缺失同样会导致种子发育停滞和 18S 和 5.8S 前 rRNA 的 3'端加工受阻，与 dek51 类似。DEK51 还与内切酶 ZmUTP24 和 ZmRCL1 相互作用，表明它可能也参与 A2 位点的切割。这些结果表明 DEK51 在促进前 rRNA 3'端加工中起关键作用。