Alternative splicing of Arabidopsis IBR5 pre-mRNA generates two IBR5 isoforms with distinct and overlapping functions.
Alternative splicing of Arabidopsis IBR5 pre-mRNA generates two IBR5 isoforms with distinct and overlapping functions.
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DOI：
10.1371/journal.pone.0102301
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Dharmasiri N
中科院分区：
文献类型：
--
作者：
Jayaweera T;Siriwardana C;Dharmasiri S;Quint M;Gray WM;Dharmasiri N
吲哚-3-丁酸应答基因(IBR5)编码一种调节植物生长素反应的双特异性磷酸酶。IBR5已被预测通过选择性剪接产生两个转录本，但IBR5的选择性剪接尚未得到实验证实。已鉴定的ibr5-1缺失突变体表现出许多与生长素相关的缺陷，如生长素不敏感的初级根生长、维管发育缺陷、身材矮小和侧根发育减慢。然而，是否所有这些缺陷都是由于磷酸酶活性不足造成的，目前还不清楚。在这里，我们描述了两个新的生长素不敏感的IBR5等位基因，ibr5-4，一个催化位点突变，和ibr5-5，一个剪接位点突变。对这些新突变体的鉴定表明，IBR5受到转录后调控，产生两个转录本，AT2G04550.1和AT2G04550.3，从而产生两个IBR5亚型，IBR5.1和IBR5.3。IBR5.1亚型具有磷酸酶催化活性，这是AUX/IAA蛋白正确降解和生长素诱导的基因表达所必需的。这两个过程由IBR5.1独立监管。新的突变等位基因与ibr5-1的比较表明，这三个突变等位基因都有许多表型。然而，每个等位基因也有明显的缺陷，涉及IBR5亚型的特定功能。其中一些功能与IBR5.1的催化活性无关。此外，对这些新突变等位基因的分析表明，IBR5可能连接了ABP1和SCFTIR1/AFBs生长素信号通路。
The INDOLE-3-BUTYRIC ACID RESPONSE5 (IBR5) gene encodes a dual specificity phosphatase that regulates plant auxin responses. IBR5 has been predicted to generate two transcripts through alternative splicing, but alternative splicing of IBR5 has not been confirmed experimentally. The previously characterized ibr5-1 null mutant exhibits many auxin related defects such as auxin insensitive primary root growth, defective vascular development, short stature and reduced lateral root development. However, whether all these defects are caused by the lack of phosphatase activity is not clear. Here we describe two new auxin insensitive IBR5 alleles, ibr5-4, a catalytic site mutant, and ibr5-5, a splice site mutant. Characterization of these new mutants indicates that IBR5 is post-transcriptionally regulated to generate two transcripts, AT2G04550.1 and AT2G04550.3, and consequently two IBR5 isoforms, IBR5.1 and IBR5.3. The IBR5.1 isoform exhibits phosphatase catalytic activity that is required for both proper degradation of Aux/IAA proteins and auxin-induced gene expression. These two processes are independently regulated by IBR5.1. Comparison of new mutant alleles with ibr5-1 indicates that all three mutant alleles share many phenotypes. However, each allele also confers distinct defects implicating IBR5 isoform specific functions. Some of these functions are independent of IBR5.1 catalytic activity. Additionally, analysis of these new mutant alleles suggests that IBR5 may link ABP1 and SCFTIR1/AFBs auxin signaling pathways.
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DOI：
10.1073/pnas.0907205106
发表时间：
2009-12-01
影响因子：
11.1
作者：
Jammes, Fabien;Song, Charlotte;Kwak, June M.
通讯作者：
Kwak, June M.
水稻 MAPK 磷酸酶 IBR5 负调控转基因烟草的干旱胁迫耐受性
影响因子：
5.2
作者：
Li, Yuge;Feng, Dongru;Wang, Jinfa
通讯作者：
Wang, Jinfa
影响因子：
7.2
作者：
Bendahmane, A;Querci, M;Baulcombe, DC
通讯作者：
Baulcombe, DC
影响因子：
11.6
作者：
Oono, Y;Chen, QG;Theologis, A
通讯作者：
Theologis, A
影响因子：
10.5
作者：
Cho, H;Kim, TK;Reinberg, D
通讯作者：
Reinberg, D