Functional diversity of Medicago truncatula RNA polymerase II CTD phosphatase isoforms produced in the Arabidopsis thaliana superexpression platform
Functional diversity of Medicago truncatula RNA polymerase II CTD phosphatase isoforms produced in the Arabidopsis thaliana superexpression platform
复制标题
拟南芥超表达平台产生的蒺藜苜蓿 RNA 聚合酶 II CTD 磷酸酶亚型的功能多样性
DOI：
10.1016/j.plantsci.2022.111309
复制
发表时间：
2022
期刊：
影响因子：
5.2
通讯作者：
Koiwa, Hisashi
中科院分区：
文献类型：
--
作者：
Fukudome, Akihito;Ishiga, Yasuhiro;Nagashima, Yukihiro;Davidson, Katherine H.;Chou, Hsiu-An;Mysore, Kirankumar S.;Koiwa, Hisashi
蒺藜苜蓿（Medicago truncatulais）是豆科植物的模式系统，其相对于原型模式双子叶植物拟南芥（Arabidopsis thaliana）显著地扩展了基因组。FCP 1（transcription factor IIF-interacting RNA polymerase II carboxyl-terminalphosphatase 1）是一种重要的转录调节因子，由一个重要的基因CPL 4（CTD-phosphatase-like 4）编码，其中M. Truncatulagenome包含4个与FCP 1/AtCPL 4同源的基因，并观察到MtCPL 4的剪接变体。使用在为植物蛋白过表达而开发的拟南芥细胞培养系统中产生的重组蛋白（MtCPL 4a 1、MtCPL 4a 2和MtCPL 4 b）分析MtCPL 4家族蛋白的功能多样化。使用高度纯化的MtCPL 4制备物的体外CTD磷酸酶测定揭示了MtCPL 4 b中有效的CTD磷酸酶活性，但不是MtCPL 4a的两种剪接变体。另一方面，对RNA聚合酶II（pol II）的植物结合测定揭示了两种MtCPL 4a变体的更大的pol II结合活性。我们的研究结果表明MtCPL 4亚型的功能多样化，并建议在植物中存在大量的功能专门的CTD-磷酸酶样蛋白。
Medicago truncatulais a model system for legume plants, which has substantially expanded the genome relative to the prototypical model dicot plant,Arabidopsis thaliana. An essential transcriptional regulator, FCP1 (transcription factor IIF-interacting RNA polymerase IIcarboxyl-terminalphosphatase 1) ortholog, is encoded by a single essential geneCPL4(CTD-phosphatase-like 4), whereasM. truncatulagenome contains four genes homologous to FCP1/AtCPL4, and splicing variants of MtCPL4 are observed. Functional diversification of MtCPL4 family proteins was analyzed using recombinant proteins (MtCPL4a1, MtCPL4a2, and MtCPL4b) produced in Arabidopsis cell culture system developed for plant protein overexpression. In vitro CTD phosphatase assay using highly purified MtCPL4 preparations revealed a potent CTD phosphatase activity in MtCPL4b, but not two splicing variants of MtCPL4a. On the other hand, in planta binding assay to RNA polymerase II (pol II) revealed a greater pol II-binding activity of both MtCPL4a variants. Our results indicate functional diversification of MtCPL4 isoforms and suggest the presence of a large number of functionally specialized CTD-phosphatase-like proteins in plants.