title: Instability in mitochondrial membranes in Polima cytoplasmic male sterility of Brassica rapa ssp. chinensis.
abstract: Cytoplasmic male sterility (CMS) is an important factor to observe heterosis in Brassica rapa. Although several studies have documented the rearrangements of mitochondrial DNA and dysfunction in the mitochondria have been observed in most types of CMS, the basis of the molecular mechanisms involved in these processes and other effects on CMS remain unclear. In this study, suppression subtractive hybridization was performed in the flowers of an alloplasmic Polima CMS system from B. rapa ssp. chinensis to identify genes that are differentially expressed between fertile and sterile plants. A total of 443 clones were isolated (156 were upregulated in fertile buds, and 287 were upregulated in sterile ones). Real-time RT-PCR further demonstrated the credibility of SSH. Among these genes, many membrane protein genes (LTP12, PIP2A, and GRP14) were inhibited in the sterile male line. Mitochondrial membrane potential (MMP) assay was then performed. Results showed that the sterile MMP was unstable and failed to create a potential difference; thus, mitochondrial dysfunction occurred. Moreover, abnormal microtubules and photosynthetic pathways were found in sterile male cells. Unstable MMP, nutritional deficiency, and abnormal microtubules were the causes of Polima CMS in Brassica campestris. H2O2, MDA, and O(2-), accumulated as byproducts of energy metabolism disorder in sterile male cells.
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Weigang 1#, Xuanwu district, Nanjing, Jiangsu, 210095, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Tongkun
authors.initials: T
authors.lastname: Liu
authors.forename: Weike
authors.initials: W
authors.lastname: Duan
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Song
authors.forename: Gongjun
authors.initials: G
authors.lastname: Shi
authors.forename: Jingyi
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Deng
authors.forename: Shuning
authors.initials: S
authors.lastname: Zhang
authors.forename: Xilin
authors.initials: X
authors.lastname: Hou
mesh_terms: D001937:Brassica / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial; D008928:Mitochondria / Q000378:metabolism* / Q000473:pathology; D051336:Mitochondrial Membranes / Q000378:metabolism* / Q000473:pathology; D024101:Mitochondrial Proteins / Q000235:genetics* / Q000378:metabolism; D018384:Oxidative Stress; D051479:Plant Infertility / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D066251:Subtractive Hybridization Techniques; D013481:Superoxides / Q000378:metabolism
chemical_list: D024101:Mitochondrial Proteins; D010940:Plant Proteins; D011994:Recombinant Proteins; D013481:Superoxides; D008315:Malondialdehyde; D006861:Hydrogen Peroxide