Dek35 Encodes a PPR Protein that Affects cis-Splicing of Mitochondrial nad4 Intron 1 and Seed Development in Maize.
In higher plants, the splicing of organelle-encoded mRNA involves a complex collaboration with nuclear-encoded proteins. Pentatricopeptide repeat (PPR) proteins have been implicated in these RNA-protein interactions. In this study, we performed the cloning and functional characterization of maize Defective kernel 35 (Dek35). The dek35-ref mutant is a lethal-seed mutant with developmental deficiency. Dek35 was cloned through Mutator tag isolation and further confirmed by four additional independent mutant alleles. Dek35 encodes an P-type PPR protein that targets the mitochondria. The dek35 mutation causes significant reduction in the accumulation of DEK35 proteins and reduced splicing efficiency of mitochondrial nad4 intron 1. Analysis of mitochondrial complex in dek35 immature seeds indicated severe deficiency in the complex I assembly and NADH dehydrogenase activity. Transcriptome analysis of dek35 endosperm revealed enhanced expression of genes involved in the alternative respiratory pathway and extensive differentially expressed genes related to mitochondrial function and activity. Collectively, these results indicate that Dek35 encodes an PPR protein that affects the cis-splicing of mitochondrial nad4 intron 1 and is required for mitochondrial function and seed development.
Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China.
Xinze
X
Chen
Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China.
Fan
F
Feng
Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China; Coordinated Crop Biology Research Center (CBRC), Beijing 100193, China.
Weiwei
W
Qi
Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China.
Liming
L
Xu
Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China.
Dongsheng
D
Yao
Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China.
Qun
Q
Wang
Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China; National Maize Improvement Center of China, China Agricultural University, Beijing 100193, China; Coordinated Crop Biology Research Center (CBRC), Beijing 100193, China. Electronic address: rentaosong@staff.shu.edu.cn.
Rentao
R
Song
D018506:Gene Expression Regulation, Plant / Q000235:genetics; D007438:Introns / Q000235:genetics*; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012326:RNA Splicing / Q000235:genetics / Q000502:physiology; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D003313:Zea mays / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
D024101:Mitochondrial Proteins; D010940:Plant Proteins; D009243:NAD
NADH; PPR; maize; mitochondria; splicing