Using single-copy conserved ortholog set (COSII) and simple sequence repeat (SSR) markers, we have constructed two genetic maps for diploid Nicotiana species, N. tomentosiformis and N. acuminata, respectively. N. acuminata is phylogenetically closer to N. sylvestris than to N. tomentosiformis, the latter two of which are thought to contribute the S-genome and T-genome, respectively, to the allotetraploid tobacco (N. tabacum L., 2n = 48). A comparison of the two maps revealed a minimum of seven inversions and one translocation subsequent to the divergence of these two diploid species. Further, comparing the diploid maps with a dense tobacco map revealed that the tobacco genome experienced chromosomal rearrangements more frequently than its diploid relatives, supporting the notion of accelerated genome evolution in allotetraploids. Mapped COSII markers permitted the investigation of Nicotiana-tomato syntenic relationships. A minimum of 3 (and up to 10) inversions and 11 reciprocal translocations differentiate the tomato genome from that of the last common ancestor of N. tomentosiformis and N. acuminata. Nevertheless, the marker/gene order is well preserved in 25 conserved syntenic segments. Molecular dating based on COSII sequences suggested that tobacco was formed 1.0MYA or later. In conclusion, these COSII and SSR markers link the cultivated tobacco map to those of wild diploid Nicotiana species and tomato, thus providing a platform for cross-reference of genetic and genomic information among them as well as other solanaceous species including potato, eggplant, pepper and the closely allied coffee (Rubiaceae). Therefore they will facilitate genetic research in the genus Nicotiana. © Springer-Verlag 2009.
COSII genetic maps of two diploid Nicotiana species provide a detailed picture of synteny with tomato and insights into chromosome evolution in tetraploid N. tabacum / F. Wu, N.T. Eannetta, Y. Xu, J. Plieske, M. Ganal, C. Pozzi, N. Bakaher, S.D. Tanksley. - In: THEORETICAL AND APPLIED GENETICS. - ISSN 0040-5752. - 120:4(2010 Feb), pp. 809-827.
|Titolo:||COSII genetic maps of two diploid Nicotiana species provide a detailed picture of synteny with tomato and insights into chromosome evolution in tetraploid N. tabacum|
|Parole Chiave:||Chromosome Mapping; Diploidy; Genome, Plant; Lycopersicon esculentum; Ploidies; Tobacco; Biological Evolution; Chromosomes, Plant; Synteny; Biotechnology; Agronomy and Crop Science; Genetics|
|Settore Scientifico Disciplinare:||Settore AGR/07 - Genetica Agraria|
|Data di pubblicazione:||feb-2010|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1007/s00122-009-1206-z|
|Appare nelle tipologie:||01 - Articolo su periodico|