INVESTIGADORES
CASTAGNARO Atilio Pedro
artículos
Título:
Isolation and diversity analysis of resistance genes analogues (RGAs) from cultivated and wild strawberries.
Autor/es:
MARTÍNEZ ZAMORA, M. G.; CASTAGNARO, A. P.; DÍAZ RICCI, JUAN CARLOS
Revista:
MOLECULAR GENETICS AND GENOMICS
Editorial:
Springer Berlin
Referencias:
Lugar: Berlín; Año: 2004 vol. 272 p. 480 - 487
ISSN:
1617-4615
Resumen:
Abstract Degenerate oligonucleotide primers, designed
based on conserved regions of Nucleotide Binding Site
(NBS) domains from previously cloned plant resistance
genes, were used to isolate Resistance Gene Analogues
(RGAs) from wild and cultivated strawberries. Seven
distinct families of RGAs of the NBS-LRR type were
identi.ed from two related wild species, Fragaria vesca
and F. chiloensis, and six di.erent Fragaria · ananassa
cultivars. With one exception (GAV-3), the deduced
amino acid sequences of strawberry RGAs showed
strong similarity to TIR (Toll Interleukin I Receptor)-
type R genes from Arabidopsis, tobacco and .ax, suggesting
the existence of common ancestors. GAV-3
seemed to be more closely related to the non-TIR type.
Further studies showed that the recombination level and
the ratio of non-synonymous to synonymous substitutions
within families were low. These data suggest that
NBS-encoding sequences of RGAs in strawberry are
subject to a gradual accumulation of mutations leading
to purifying selection, rather than to a diversifying
process. The present paper is the .rst report on RGAs in
strawberry.