Cloning of S-haplotype-specific F-box genes from Prunus armeniaca cultivars in Xinjiang

• 26 SFB gene of apricot cultivars native to variety group of central Asia in China had been identified.
• 19 new SFB gene sequences had been cloned in apricot cultivars of central Asia in China.
• 2 new complete SFB sequences of apricot had been cloned.

We used RT-PCR to identify nineteen new partial sequences and two additional complete sequences in 26 Prunus armeniaca cultivars native to Central Asia. These sequences are homologous to parts of F-box genes found in other Prunus species (65.7–99.3% amino acid identity), and share features of their basic gene structures, which include defined amino acid domains. Analysis of the 5′ terminal regions of the two entire coding sequences indicates the presence of a conserved F-box region. Other regions have two variable regions, named V1 and V2, as well as two hypervariable regions. Phylogenetic analysis revealed that SFB33, SFB38, and SFB47 clustered together, and were distantly related to the other SFB gene we identified. The SFB50 gene was closely related to a SFB gene from Prunus pseudocerasus, suggesting that the interspecies amino acid identities obtained by comparison with other Prunus SFB genes were greater than the intraspecies identities. The new sequences have been deposited in GenBank, with accession numbers HQ148064–HQ148083, JN019789, and JN019790. Our findings may enable more efficient breeding of Chinese apricot and further molecular characterization of SFB genes.