Gonçalo Santos Silva1, Margarete Magalhães Souza2, Vanessa Carvalho Cayres Pamponét1. 1. Laboratório de Melhoramento de Plantas (LAMEP), Departamento de Ciências Biológicas (DCB), Universidade Estadual de Santa Cruz (UESC), Rod. Jorge Amado, Km 16, Salobrinho, Ilhéus, BA, 45662-900, Brasil. 2. Laboratório de Melhoramento de Plantas (LAMEP), Departamento de Ciências Biológicas (DCB), Universidade Estadual de Santa Cruz (UESC), Rod. Jorge Amado, Km 16, Salobrinho, Ilhéus, BA, 45662-900, Brasil. souzamagg@yahoo.com.br.
Abstract
BACKGROUND: The 45S rDNA is considered the most useful chromosomal marker for cytogenetic analysis of Passiflora. Amplification of 45S rDNA sequence via PCR are more advantageous than sequence maintenance in vectors for chromosomal hybridization via FISH. We aimed both to identify 45S rDNA by sequencing data for chromosomal localization and to verify the relationship between GC content and CMA3/DAPI banding. METHODS AND RESULTS: Low-coverage sequencing of Passiflora alata, P. cincinnata, and P. edulis was performed, and 45S rDNA units were identified using RepeatExplorer. The 45S rDNA units were used to construct a neighbor-joining tree to verify the similarities between the three species' 18S and 26S rDNA sequences. Clusters (CL)116 (P. alata), CL71 (P. cincinnata), and CL116 (P. edulis) were remarkably similar among the three species, and the 26S rDNA sequences of the clusters were similar to those of Populus tremuloides, Salix interior, and Averrhoa carambola (98% identity). The 26S rDNA was cytologically localized in the chromosomes of P. edulis, P. bahiensis, and the backcrossed hybrid (P. sublanceolata vs. HD13). The hybridization transfer capacity was evaluated in Citrus sunki and Cucumis melo. Finally, a chromosomal pair with a heteromorphic 26S rDNA site was observed in P. edulis, which was the same to that observed for CMA3. CONCLUSION: The amplification of the 26S rDNA in Passiflora via PCR and the chromosomal localization in Passiflora and other plant species was successfully achieved. The CMA3 bands were found to be related not only to the amount of GC but also to its structure and the number of repetitions.
BACKGROUND: The 45S rDNA is considered the most useful chromosomal marker for cytogenetic analysis of Passiflora. Amplification of 45S rDNA sequence via PCR are more advantageous than sequence maintenance in vectors for chromosomal hybridization via FISH. We aimed both to identify 45S rDNA by sequencing data for chromosomal localization and to verify the relationship between GC content and CMA3/DAPI banding. METHODS AND RESULTS: Low-coverage sequencing of Passiflora alata, P. cincinnata, and P. edulis was performed, and 45S rDNA units were identified using RepeatExplorer. The 45S rDNA units were used to construct a neighbor-joining tree to verify the similarities between the three species' 18S and 26S rDNA sequences. Clusters (CL)116 (P. alata), CL71 (P. cincinnata), and CL116 (P. edulis) were remarkably similar among the three species, and the 26S rDNA sequences of the clusters were similar to those of Populus tremuloides, Salix interior, and Averrhoa carambola (98% identity). The 26S rDNA was cytologically localized in the chromosomes of P. edulis, P. bahiensis, and the backcrossed hybrid (P. sublanceolata vs. HD13). The hybridization transfer capacity was evaluated in Citrus sunki and Cucumis melo. Finally, a chromosomal pair with a heteromorphic 26S rDNA site was observed in P. edulis, which was the same to that observed for CMA3. CONCLUSION: The amplification of the 26S rDNA in Passiflora via PCR and the chromosomal localization in Passiflora and other plant species was successfully achieved. The CMA3 bands were found to be related not only to the amount of GC but also to its structure and the number of repetitions.
Authors: Jiří Macas; Eduard Kejnovský; Pavel Neumann; Petr Novák; Andrea Koblížková; Boris Vyskot Journal: PLoS One Date: 2011-11-09 Impact factor: 3.240
Authors: Wencai Wang; Lu Ma; Hannes Becher; Sònia Garcia; Alena Kovarikova; Ilia J Leitch; Andrew R Leitch; Ales Kovarik Journal: Chromosoma Date: 2015-12-05 Impact factor: 4.316