Transcriptional control of orf224/atp6 by the pol CMS restorer Rfp gene in Brassica napus L.
In order to investigate effects of fertility restorer gene Rfp on expression of orf224/atp6, Northern analyses of floral mitochondrial RNA (mtRNA) from polima (pol) CMS three lines were conducted using 10 probes of mitochondrial genes in this paper. Differences in transcriptional patterns were observed only with the probes atp6, orf224 and orf222. The atp6 probe detected a single, 1.1 kb transcript with strong abundance in the male fertile 1141B (nap cytoplasm). In the male sterile 1141A (pol cytoplasm) and fertile restorer line 1141R (pol cytoplasm), levels of this transcript appeared greatly reduced, and two longer transcripts of 2.2 and 1.9 kb were observed. Compared with 1141A, levels of the 2.2 and 1.9 kb transcripts appeared to be slightly reduced in the restorer line 1141R, and two additional transcripts of 1.3 and 1.4 kb were observed. The results suggested that the expression of orf224/atp6 gene region was associated with pol CMS and regulated by Rfp gene. In contrast to floral buds of the male sterile 1141A, the 1.4 kb transcript specific to fertility-restored plants was also observed in seedlings of 1141A. Possible mechanisms by which transcriptional alteration of orf224/atp6 between floral buds and seedlings of 1141A may be related to nuclear genotypes and relatively low temperature are discussed.
Yuan
Mei
M
National Key Laboratory of Crop Genetic Improvement, National Rapeseed Improvement Sub-center (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
Yang
Guang-Sheng
GS
Fu
Ting-Dong
TD
Li
Yun
Y
D029688:Brassica napus / Q000235:genetics*; D003001:Cloning, Molecular; D005298:Fertility; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000502:physiology*; D016366:Open Reading Frames; D012313:RNA / Q000032:analysis*; D000077278:RNA, Mitochondrial; D036226:Seedlings / Q000378:metabolism; D014158:Transcription, Genetic
D000077278:RNA, Mitochondrial; D012313:RNA