A homolog of the RPS2 disease resistance gene is constitutively expressed in Brassica oleracea
Genet. mol. biol
; 26(4): 511-516, dec. 2003. ilus
Article
in English
| LILACS
| ID: lil-355297
Responsible library:
BR26.1
RESUMO
In this study, we identified disease resistance gene homologs in Brassica oleracea and assessed their expression in lines resistant and susceptible to Xanthomonas campestris pv. campestris (Xcc). Two DNA fragments of approximately 2.5 kb (BI-16/RPS2 and Lc201/RPS2) were amplified by PCR from two Brassica lines using primers based on an RPS2 homologous sequence previously described in the Brassica oleracea ecotype B117. The sequences of these fragments shared high similarity (95-98 percent) with RPS2 homologs from various Brassica species. The digestion of these fragments with restriction enzymes revealed polymorphisms at the Xba I restriction sites. The length polymorphisms were used as a co-dominant marker in an F2 population developed to segregate for resistance to Xcc, the causal agent of black rot. Linkage analysis showed no significant association between the marker and quantitative trait loci for black rot. RT-PCR with specific primers yielded an expected 453 bp fragment that corresponded to the RPS2 homologs in both resistant and susceptible lines inoculated with the pathogen, as well as in non-inoculated control plants. These results suggest that these homologs are constitutively expressed in B. oleracea.
Full text:
Available
Collection:
International databases
Database:
LILACS
Main subject:
Polymorphism, Genetic
/
Brassica
/
Polymerase Chain Reaction
Language:
English
Journal:
Genet. mol. biol
Journal subject:
Genetics
Year:
2003
Document type:
Article
/
Project document
Affiliation country:
Brazil
Institution/Affiliation country:
Universidade de São Paulo/BR