Euchromatin and pericentromeric heterochromatin: comparative composition in the tomato genome.

ABSTRACT: Eleven sequenced BACs were annotated and localized via FISH to tomato pachytene chromosomes providing the first global insights into the compositional differences of euchromatin and pericentromeric heterochromatin in this model dicot species. The results indicate that tomato euchromatin has a gene density (6.7 kb/gene) similar to that of Arabidopsis and rice. Thus, while the euchromatin comprises only 25% of the tomato nuclear DNA, it is sufficient to account for approximately 90% of the estimated 38,000 nontransposon genes that compose the tomato genome. Moreover, euchromatic BACs were largely devoid of transposons or other repetitive elements. In contrast, BACs assigned to the pericentromeric heterochromatin had a gene density 10-100 times lower than that of the euchromatin and are heavi

SUBMITTER: Wang Y 

PROVIDER: S-EPMC1456407 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature