Plant Mitochondrial And Cytoplasmic Male Sterility

Mitochondrial genomes encode only a fraction of the genetic information required for their biogenesis and function. Consequently, a large number of genetic and biochemical features present in plant mitochondria arose in the context of coevolution and coordinated gene functions between the mitochondrial and nuclear genomes. Cytoplasmic male sterility (CMS) is a widespread phenomenon observed plant species. CMS is amaternally inherited trait and is often associated with unusual open reading frames (ORFs) found in mitochondrial genomes, and in many instances, Cytoplasmic male sterility can be restored fertility specifically by nuclear- encoded protein, fertility restorer (Rf) genes.Therefore, CMS/Rf systems are ideal models for studying the genetic interaction and cooperative function of mitochondrial and nuclear genomes in plants.In this paper, with near isogenic lines of restoring gene as materials, proteomics techniques and methods are adopted to study the molecular basis of V-CMS wheat and analyze the differential mitochondrial proteins with V-CMS, as well as genetic analysis of male sterile cytoplasm of Ta-CMS in maize. The major results are shown as follows:1. With near isogenic lines of restoring gene to wheat V-CMS as materials, we establish the mitochondrial protein expression profiles by 2-DE . (1) Comparing etiolated seedlings with ears mitochondrial protein expression profiles, and identifying ten differential mitochondrial proteins, including energy metabolism proteins about F0-F1 ATPase complex subunit and unknown proteins, these confirm that mitochondrial protein express with tissue-specific and time- specific; (2)Comparing V-CMS with hybrid F1 mitochondrial protein expression profiles in wheat etiolated seedlings and ears. We identified twelve differential mitochondrial proteins, and energy metabolism proteins, for example, ATP synthase beta subunit and NADH dehydrogenase subunit J. After analyzing the differential mitochondrial proteins, we presume that mitochondrial retrograde regulation of the accumulation of nuclear-encoded proteins in the mitochondrial proteome of wheat, V-CMS gene encode protein impact the expression level of enegy metabolism proteins in mitochondrial, V-CMS in wheat maybe associated with premature programmed cell death,but we shoud do advanced study.2.Ta-CMS was attained by treatment of Chang 7-2 with Co-60γ, and it was studied by using combined methods of restoring and maintaining testing as well as PCR classifying. One hundred and thirty-seven maize inbred lines or hybrids including Tr,K55,W23,B37,CML311 were used as testers to identity whether they have restoring gene or not, the results showed that CL1325, P138 and'nongda80/teosinte'could restore the fertility of TaChang7-2CMS and TaMo17CMS, which indicted that there were potential restoring gene to Ta-CMS in tropic idioplasm. Comparing of male sterile gene of TaChang7-2CMS and TaMo17CMS with T-CMS by PCR and recovering as well as sequencing indicated that Ta-CMS maybe a subgroup of T-CMS cytoplast.