Phosphorylation of the smooth muscle master splicing regulator RBPMS regulates its splicing activity.
Phosphorylation of the smooth muscle master splicing regulator RBPMS regulates its splicing activity.
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平滑肌主剪接调节器RBPM的磷酸化调节其剪接活性。
DOI：
10.1093/nar/gkac1048
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发表时间：
2022-11-11
影响因子：
14.9
通讯作者：
Smith, Christopher W. J.
中科院分区：
文献类型：
--
作者：
Barnhart, Michael D.;Yang, Yi;Nakagaki-Silva, Erick E.;Hammond, Thomas H.;Pizzinga, Mariavittoria;Gooding, Clare;Stott, Katherine;Smith, Christopher W. J.
我们以前确定RBPMS作为一个主调节器的选择性剪接在分化的平滑肌细胞（SMC）。RBPMS在SMC去分化过程中转录下调，但我们假设RBPMS蛋白活性可能通过翻译后修饰急剧下调。公开的磷酸化蛋白质组学数据显示，与RRM结构域紧邻的Thr 113和Thr 118通常都被磷酸化。RBPMS T113/118磷酸化模拟T/E突变体在转染细胞和无细胞体外试验中均显示剪接调节活性降低，而非磷酸化T/A突变体保留全部活性。剪接活性的丧失与RNA亲和力的适度降低有关，但核提取物中的RNA结合显著降低。T/E突变体寡聚化程度较低可能导致多价RNA结合的亲合力较低。然而，NMR分析还揭示了T113/118 E肽作为RNA模拟物，其可以环回并拮抗RRM结构域的RNA结合。最后，我们确定ERK 2是最有可能负责Thr 113和Thr 118磷酸化的激酶。总的来说，我们的数据确定了一个潜在的机制，快速调制的SMC剪接程序在血管损伤反应和动脉粥样硬化形成过程中的外部信号。在平滑肌细胞表型转变开始期间，RBPMS的磷酸化导致剪接调控的丧失，这是由于去寡聚化和RRM闭塞引起的RNA结合减少。
We previously identified RBPMS as a master regulator of alternative splicing in differentiated smooth muscle cells (SMCs). RBPMS is transcriptionally downregulated during SMC dedifferentiation, but we hypothesized that RBPMS protein activity might be acutely downregulated by post-translational modifications. Publicly available phosphoproteomic datasets reveal that Thr113 and Thr118 immediately adjacent to the RRM domain are commonly both phosphorylated. An RBPMS T113/118 phosphomimetic T/E mutant showed decreased splicing regulatory activity both in transfected cells and in a cell-free in vitro assay, while a non-phosphorylatable T/A mutant retained full activity. Loss of splicing activity was associated with a modest reduction in RNA affinity but significantly reduced RNA binding in nuclear extract. A lower degree of oligomerization of the T/E mutant might cause lower avidity of multivalent RNA binding. However, NMR analysis also revealed that the T113/118E peptide acts as an RNA mimic which can loop back and antagonize RNA-binding by the RRM domain. Finally, we identified ERK2 as the most likely kinase responsible for phosphorylation at Thr113 and Thr118. Collectively, our data identify a potential mechanism for rapid modulation of the SMC splicing program in response to external signals during the vascular injury response and atherogenesis. Phosphorylation of RBPMS during the onset of smooth muscle cell phenotypic transition leads to loss of splicing regulation due to reduced RNA binding caused by deoligomerization and RRM occlusion.
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影响因子：
7.3
作者：
Kettenbach AN;Schweppe DK;Faherty BK;Pechenick D;Pletnev AA;Gerber SA
通讯作者：
Gerber SA
DOI：
10.1161/atvbaha.110.221135
发表时间：
2011-07
期刊：
Arteriosclerosis, thrombosis, and vascular biology
影响因子：
--
作者：
Mack CP
通讯作者：
Mack CP
影响因子：
15
作者：
Hyberts, Sven G.;Takeuchi, Koh;Wagner, Gerhard
通讯作者：
Wagner, Gerhard
影响因子：
16.8
作者：
Kim, Myoung Ok;Kim, Sung-Hyun;Dong, Zigang
通讯作者：
Dong, Zigang
影响因子：
64.5
作者：
Hallegger M;Chakrabarti AM;Lee FCY;Lee BL;Amalietti AG;Odeh HM;Copley KE;Rubien JD;Portz B;Kuret K;Huppertz I;Rau F;Patani R;Fawzi NL;Shorter J;Luscombe NM;Ule J
通讯作者：
Ule J