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 proteins. Pentatricopeptide repeat(PPR) proteins have key roles in C-to-U editing. Owing to its large number,however, the biological functions of many PPR proteins remain to be identified. Through characterizing a small kernel4(smk4) mutant, here we report the function of Smk4 and its r...

【文章頁數】：16 頁

【文章目錄】：
INTRODUCTION
RESULTS
    Phenotypic and genetic analyses of smk4‐1 mutants
    Embryo and endosperm development are delayed in smk4‐1 mutants
    Cloning of Smk4
    Smk4 encodes an E‐subclass PPR protein that is targeted to mitochondria
    SMK4 is required for C‐to‐U editing of mitochondrial cox1 transcript
    Mitochondrial complex IV activity is significantly reduced in smk4 mutants
    Activation of alternative respiratory pathway in smk4‐1 mutants
DISCUSSION
    SMK4 is required for C‐to‐U editing of the cox1‐1489 site
    The Ser‐497 residue is important for Cox1 function and mitochondrial complex IV activity
    Loss of SMK4 function delays seed development and plant growth in maize
MATERIALS AND METHODS
    Plant materials
    DNA extraction and linkage analysis
    Light microscopy of cytological sections
    Subcellular localization of SMK4
    RNA extraction,RT‐PCR,and qRT‐PCR
    Analysis of mitochondrial RNA editing
    Analysis of mitochondrial transcript abundance
    BN‐PAGE,in‐gel activity staining of complex I and complex IV,and western blotting assay
    Phylogenetic analysis and protein structure modeling
    Accession numbers
AUTHOR CONTRIBUTIONS
SUPPORTING INFORMATION



本文編號：3869258