title: MORF9 increases the RNA-binding activity of PLS-type pentatricopeptide repeat protein in plastid RNA editing.
abstract: RNA editing is a post-transcriptional process that modifies the genetic information on RNA molecules. In flowering plants, RNA editing usually alters cytidine to uridine in plastids and mitochondria. The PLS-type pentatricopeptide repeat (PPR) protein and the multiple organellar RNA editing factor (MORF, also known as RNA editing factor interacting protein (RIP)) are two types of key trans-acting factors involved in this process. However, how they cooperate with one another remains unclear. Here, we have characterized the interactions between a designer PLS-type PPR protein (PLS)3PPR and MORF9, and found that RNA-binding activity of (PLS)3PPR is drastically increased on MORF9 binding. We also determined the crystal structures of (PLS)3PPR, MORF9 and the (PLS)3PPR-MORF9 complex. MORF9 binding induces significant compressed conformational changes of (PLS)3PPR, revealing the molecular mechanisms by which MORF9-bound (PLS)3PPR has increased RNA-binding activity. Similarly, increased RNA-binding activity is observed for the natural PLS-type PPR protein, LPA66, in the presence of MORF9. These findings significantly expand our understanding of MORF function in plant organellar RNA editing.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Junjie
authors.initials: J
authors.lastname: Yan
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Qunxia
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Zeyuan
authors.initials: Z
authors.lastname: Guan
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Fengying
authors.initials: F
authors.lastname: Ruan
authors.affiliation: Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Rongcheng
authors.initials: R
authors.lastname: Lin
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Zou
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yin
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002736:Chloroplasts / Q000502:physiology; D017393:RNA Editing; D018749:RNA, Plant / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C543426:Lpa66 protein, Arabidopsis; C000622451:MORF9 protein, Arabidopsis; D018749:RNA, Plant; D016601:RNA-Binding Proteins