SMALL KERNEL4 is required for mitochondrial cox1 transcript editing and seed development in maize

作     者：Hong-Chun Wang Aqib Sayyed Xin-Yuan Liu Yan-Zhuo Yang Feng Sun Yong Wang Miaodi Wang Bao-Cai Tan Hong-Chun Wang;Aqib Sayyed;Xin-Yuan Liu;Yan-Zhuo Yang;Feng Sun;Yong Wang;Miaodi Wang;Bao-Cai Tan

作者机构：Key Laboratory of Plant Development and Environment Adaptation BiologyMinistry of EducationSchool of Life SciencesShandong UniversityQingdao 266237China 

出 版 物：《Journal of Integrative Plant Biology》 (植物学报（英文版）)

年 卷 期：2020年第62卷第6期

页      面：777-792页

核心收录：

学科分类：09[农学] 0901[农学-作物学] 

基　　金：the National Natural Science Foundation of China(31630053 91735301 and 91435201) 

主　　题：cox1 editing maize 

摘      要：In land plants,cytidine-to-uridine(C-to-U)editing of organellar transcripts is an important posttranscriptional process,which is considered to remediate DNA genetic mutations to restore the coding of functional *** repeat(PPR)proteins have key roles in C-to-U *** to its large number,however,the biological functions of many PPR proteins remain to be *** characterizing a small kernel4(smk4)mutant,here we report the function of Smk4 and its role in maize growth and *** mutation of Smk4 slows plant growth and development,causing small plants,delayed flowering time,and small *** revealed that Smk4 encodes a new E-subclass PPR protein,and localization indicated that SMK4 is exclusively localized in *** of Smk4 function abolishes C-to-U editing at position 1489 of the cytochrome c oxidase1(cox1)transcript,causing an amino acid change from serine to proline at 497 in ***1 is a core component of mitochondrial complex ***,complex IV activity is reduced in the smk4,along with drastically elevated expression of alternative oxidases(AOX).These results indicate that SMK4 functions in the C-to-U editing of cox1-1489,and this editing is crucial for mitochondrial complex IV activity,plant growth,and kernel development in maize.