RRC ID 3672
Author Chung MC, Lee YI, Cheng YY, Chou YJ, Lu CF.
Title Chromosomal polymorphism of ribosomal genes in the genus Oryza.
Journal Theor Appl Genet
Abstract The genes encoding for 18S-5.8S-28S ribosomal RNA (rDNA) are both conserved and diversified. We used rDNA as probe in the fluorescent in situ hybridization (rDNA-FISH) to localized rDNAs on chromosomes of 15 accessions representing ten Oryza species. These included cultivated and wild species of rice, and four of them are tetraploids. Our results reveal polymorphism in the number of rDNA loci, in the number of rDNA repeats, and in their chromosomal positions among Oryza species. The numbers of rDNA loci varies from one to eight among Oryza species. The rDNA locus located at the end of the short arm of chromosome 9 is conserved among the genus Oryza. The rDNA locus at the end of the short arm of chromosome 10 was lost in some of the accessions. In this study, we report two genome specific rDNA loci in the genus Oryza. One is specific to the BB genome, which was localized at the end of the short arm of chromosome 4. Another may be specific to the CC genome, which was localized in the proximal region of the short arm of chromosome 5. A particular rDNA locus was detected as stretched chromatin with bright signals at the proximal region of the short arm of chromosome 4 in O. grandiglumis by rDNA-FISH. We suggest that chromosomal inversion and the amplification and transposition of rDNA might occur during Oryza species evolution. The possible mechanisms of cyto-evolution in tetraploid Oryza species are discussed.
Volume 116(6)
Pages 745-53
Published 2008-4-1
DOI 10.1007/s00122-007-0705-z
PMID 18214422
PMC PMC2271086
MeSH Chromosomes, Plant / genetics* DNA, Ribosomal / genetics* DNA, Ribosomal Spacer Genome, Plant* In Situ Hybridization, Fluorescence Oryza / genetics* Polymorphism, Genetic* RNA, Ribosomal, 18S / genetics* RNA, Ribosomal, 28S / genetics* RNA, Ribosomal, 5S / genetics*
IF 4.439
Times Cited 50
Rice W0025 W1623 W0107 W1577 W1593 W1564 W0045 W0567 W0613 W0019 W0542 W1174 W0008