Abstract:
Microsatellite-enhanced genomic library of the tiger shrimp
Penaeus monodon was constructed using repeat-enrichment method with biotin-labeled oligos (CA)
12, (AG)
12 and (TA)
16 and streptavidin magnetic beads. From a total of randomly selected 254 clones, 51 clones (20.1%) were positive after PCR selection. Of which, 32 clones comes from (CA)
12 probe-used library, the left from (AG)
12 probe-used library. 48 clones are discovered to contain microsatellites. By alignment, 40 special microsatellite clones are confirmed finally. (GA)
n and (CA)
n were the abundant microsatellite motifs with a percentage of 20.7% and 60.4% in the isolated microsatellites. Several other types of repeat sequences were detected, including repeats consisting of (AT)
n, (GC)
n, (TGG)
n, (AAG)
n, (AAT)
n, (GAA)
n, (GTGC)
n, (GCGT)
n, (GGTTA)
n, (GTGCGT)
n making up to 18.9%. Characterization of these microsatellites showed that 76 (68.5%) sequences were classified as perfect type, 22 (19.8%) as imperfect type and 13 (11.7%) as compound type. The repeat units of (GT/CA)
n ranged from 3 to 52 was much more than the units of (GA/CT)
n ranged from 3 to 27. The sequence size ranges from 129 to 601 bp with an average of 286 bp. This study provides a base for molecular breeding and assessment of germplasm resources of the tiger shrimp in future.