Oryza granulata Nees et Arn. ex Watt. is one of the three wild relatives of rice, which are the most valuable for study and utilization in China. In this study, the homol-ogy and physical locations of three rice resis...Oryza granulata Nees et Arn. ex Watt. is one of the three wild relatives of rice, which are the most valuable for study and utilization in China. In this study, the homol-ogy and physical locations of three rice resistance genes, Glh, Bph-3 and xa-5 are comparatively analyzed between O. sativa and O. granulata by Southern blotting and fluorescence in situ hybridization (FISH). The results of Southern blotting indicate that there exist homologous sequences of the tested RFLP markers in O. granulata. By using three bacterial arti-ficial chromosome (BAC) clones scanned by the tested RFLP as probes, FISH signals are detected on both mitotic and pachytene chromosomes in O. sativa and O. granulata. Dual-color FISH demonstrates that two of the three BAC clones (14E16 and 38J9) are located on the short arm of the same chromosome pair in O. granulata. Additionally, colin-earity is shown for the two clones between O. sativa and O. granulata. Another BAC clone 44B4 is located on the end of the short arm of other chromosome pair in these two species. Although the phylogenetic relationship between O. sativa and O. granulata is the most distinct in Oryza and these two spe-cies have evidently different biological features and ecologi-cal habits, the relative lengths and arm ratios of the detected chromosomes and the relative positions of the tested clone signals on chromosomes in O. granulata are quite similar to those in O. sativa.展开更多
Knob-associated tandem repeats, 180-bp repeats and TR-1 elements, together with 45S rDNA were located on mitotic chromosomes of Zea diploperennis (DP),maize inbred line F102 and their hybrid. In DP, knobs on the short...Knob-associated tandem repeats, 180-bp repeats and TR-1 elements, together with 45S rDNA were located on mitotic chromosomes of Zea diploperennis (DP),maize inbred line F102 and their hybrid. In DP, knobs on the short arm of chromosomes 1 and 4 and on the long arm ofthe chromosomes 4 and 5 are composed predominantly of the 180-bp repeats. In addition, 180-bp repeats existed together with TR-1 elements were also detected on the short arm ofchromosomes 2 and 5 and on the long arm of the chromosomes 2, 6, 7, 8 and 9. In maize inbred line F102, 180-bp repeats were present in chromosomes 7S and one homologue of chromosomes 8L. TR-1 elements appeared on satellite of chromosome 6 and no detectable hybridization site co-located with 180-bp repeats was observed in maize F102.Polymorphism of size, number, and distribution of 180-bp and TR-1 signals were revealed among different chromosomes in these two species and heteromorphism existed between some homologous chromosomes in the same species.Using these excellent landmarks, the interspecific hybrid of maize and DP were identified. The results suggest that comparative analysis of 180-bp repeats and TR-1 elements may help understand the genome organization and the evolution in Zea.展开更多
文摘Oryza granulata Nees et Arn. ex Watt. is one of the three wild relatives of rice, which are the most valuable for study and utilization in China. In this study, the homol-ogy and physical locations of three rice resistance genes, Glh, Bph-3 and xa-5 are comparatively analyzed between O. sativa and O. granulata by Southern blotting and fluorescence in situ hybridization (FISH). The results of Southern blotting indicate that there exist homologous sequences of the tested RFLP markers in O. granulata. By using three bacterial arti-ficial chromosome (BAC) clones scanned by the tested RFLP as probes, FISH signals are detected on both mitotic and pachytene chromosomes in O. sativa and O. granulata. Dual-color FISH demonstrates that two of the three BAC clones (14E16 and 38J9) are located on the short arm of the same chromosome pair in O. granulata. Additionally, colin-earity is shown for the two clones between O. sativa and O. granulata. Another BAC clone 44B4 is located on the end of the short arm of other chromosome pair in these two species. Although the phylogenetic relationship between O. sativa and O. granulata is the most distinct in Oryza and these two spe-cies have evidently different biological features and ecologi-cal habits, the relative lengths and arm ratios of the detected chromosomes and the relative positions of the tested clone signals on chromosomes in O. granulata are quite similar to those in O. sativa.
文摘Knob-associated tandem repeats, 180-bp repeats and TR-1 elements, together with 45S rDNA were located on mitotic chromosomes of Zea diploperennis (DP),maize inbred line F102 and their hybrid. In DP, knobs on the short arm of chromosomes 1 and 4 and on the long arm ofthe chromosomes 4 and 5 are composed predominantly of the 180-bp repeats. In addition, 180-bp repeats existed together with TR-1 elements were also detected on the short arm ofchromosomes 2 and 5 and on the long arm of the chromosomes 2, 6, 7, 8 and 9. In maize inbred line F102, 180-bp repeats were present in chromosomes 7S and one homologue of chromosomes 8L. TR-1 elements appeared on satellite of chromosome 6 and no detectable hybridization site co-located with 180-bp repeats was observed in maize F102.Polymorphism of size, number, and distribution of 180-bp and TR-1 signals were revealed among different chromosomes in these two species and heteromorphism existed between some homologous chromosomes in the same species.Using these excellent landmarks, the interspecific hybrid of maize and DP were identified. The results suggest that comparative analysis of 180-bp repeats and TR-1 elements may help understand the genome organization and the evolution in Zea.
