Abstract:

It is important to obtain sequence information on retrotransposons for detecting their behavior in the host genome and for studing the phylogenetic relationship in many crops. Thirty-one RNaseH-long terminal repeat (LTR) sections of the Ty1-copia like retrotransposon clones were isolated from oriental persimmon (Diospyros kaki Thunb. 'Luotian-tianshi') successfully, and IRAP analysis were performed in order to illustrate retrotransposon groups corresponding to several sequences transcriptional activity and distribution in oriental persimmon genome. Both sequence multiple alignment and the phylogenetic analysis indicated that at least ten subgroups were amplified, and high sequence heterogeneity that was due to nucleotide replacement, insertion or deletion and amino acid replacement, stop codon and frameshift mutations in translated putative amino acid sequences were found among the different subgroups. But some clones showed high similarity within the same subgroup, it may exhibit the mutual benefit relationship between the host genome and retrotransposons. The IRAP analysis suggested that retrotransposon are ubiquitous, generally dispersed, high copy and high transcriptional activity in Diospyros spp., and their multiple insertion patterns indicated that the potential of these RNaseH-LTR sequences for developing novel retrotransposon molecular markers.

Key words: Diospyros kaki Thunb., Ty1-copia retrotransposon, suppression PCR, long terminal repeat (LTR), inter-retrotransposon amplified polymorphism (IRAP)