Retrograde regulation of nuclear gene expression in CW-CMS of rice.
The CW-cytoplasmic male sterility (CMS) line has the cytoplasm of Oryza rufipogon Griff, and mature pollen is morphologically normal under an optical microscope but lacks the ability to germinate; restorer gene Rf17 has been identified as restoring this ability. The difference between nuclear gene expression in mature anthers was compared for the CW-CMS line, [cms-CW] rf17rf17, and a maintainer line with normal cytoplasm of Oryza sativa L., [normal] rf17rf17. Using a 22-k rice oligoarray we detected 58 genes that were up-regulated more than threefold in the CW-CMS line. Expression in other organs was further investigated for 20 genes using RT-PCR. Five genes, including genes for alternative oxidase, were found to be preferentially expressed in [cms-CW] rf17rf17 but not in [normal] rf17rf17 or [cms-CW] Rf17Rf17. Such [cms-CW] rf17rf17-specific gene expression was only observed in mature anthers but not in leaves, stems, or roots, indicating the presence of anther-specific mitochondrial retrograde regulation of nuclear gene expression, and that Rf17 has a role in restoring the ectopic gene expression. We also used a proteomic approach to discover the retrograde regulated proteins and identified six proteins that were accumulated differently. These results reveal organ-specific induced mitochondrial retrograde pathways affecting nuclear gene expression possibly related to CMS.
Fujii
Sota
S
Laboratory of Environmental Biotechnology, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
Komatsu
Setsuko
S
Toriyama
Kinya
K
D002467:Cell Nucleus / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D050259:Genes, Mitochondrial; D017343:Genes, Plant; D018525:Germination / Q000235:genetics; D012275:Oryza / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D011058:Pollen / Q000235:genetics; D040901:Proteomics