Genomic organization, rapid evolution and meiotic instability of nucleotide-binding-site-encoding genes in a new fruit crop, "chestnut rose".

ABSTRACT: From chestnut rose, a promising fruit crop of the Rosa genus, powdery mildew disease-resistant and susceptible genotypes and their F(1) progeny were used to isolate nucleotide-binding-site (NBS)-encoding genes using 19 degenerate primer pairs and an additional cloning method called overlapping extension amplification. A total of 126 genes were harvested; of these, 38 were from a resistant parent, 37 from a susceptible parent, and 51 from F(1) progeny. A phylogenetic tree was constructed, which revealed that NBS sequences from parents and F(1) progeny tend to form a mixture and are well distributed among the branches of the tree. Mapping of these NBS genes suggested that their organization in the genome is a "tandem duplicated cluster" and, to a lesser extent, a "heterogeneous cluster." Int

SUBMITTER: Xu Q 

PROVIDER: S-EPMC2323798 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature