Rc. Ma et Mm. Oliveira, Molecular cloning of the self-incompatibility genes S1 and S3 from almond (Prunus dulcis cv. Ferragnes), SEX PLANT R, 14(3), 2001, pp. 163-167
Almond (Prunes dulcis) displays gametophytic self-incompatibility. In the w
ork reported here, we cloned two novel S-RNase genes from almond cultivar F
erragnes (genotype S1S3) using PCR. The S1-RNase gene has the same coding r
egion as the Sb gene cloned from almond cultivated in the USA; however, the
ir introns are different in sequence. S1 was cloned and sequenced from six
different cultivars originating in Europe. The full-length of the S3-RNase
gene was cloned using two primers corresponding to the start and stop codon
s contexts. Two introns are present in the S3 gene, unique among the S-RNas
e genes. Sequence-specific PCR was performed to confirm that the two cloned
genes co-segregate with the S-locus using progenies of a controlled cross
between Tuono (S1Sf) and Ferragnes (S1S3). Based on the structural differen
ces of S-and S-like RNase genes, we discuss the evolutionary relationship b
etween the two groups of RNase genes.