Abstract:

The (CA)_n DNA sequences in Lutjanus russelli were isolated through PCR arrays, and the characteristics of the microsatellite were analyzed. DNA was extracted from a sample of Lutjanus russelli, and digested with HaeⅢ+DraⅠ. The fragments were ligated to pUCm-T vector and transferred into DH5α to construct a genomic library. The positive clones were isolated with universal M13 reverse and forward primers, M13 forward primer and the simple sequence repeats (SSRs) probes (CA)15, M13 reverse primer and (CA)₁₅. After twice isolation, 121 positive clones, whose PCR products with M13 forward primer and probes (CA)₁₅ or M13 reverse primer and (CA)₁₅ were smaller than those with universal M13 reverse and forward primers probably contained microsatellites, were obtained. Then, 53 (CA)_n(n≥7) microsatellites were obtained by sequencing. The repeat length mainly distributed in 7-15(80.77%). Besides (CA)_n repeats, other repeat motifs, such as A_n, (CAC)n and (AACA)n, were also obtained. Scorable and constant amplification of DNA fragments were observed with 48 pairs of SSR primers designed from the flank sequences. This research makes a positive contribution to explorating ge-nomes of Lutjanus russelli, offers genetic tools to examine the genetic variations and constructs genetic linkage map.
Keywords: microsatellite; Lutjanus russelli; PCR