Distribution and comparative analysis of whole genome microsatellite in Sebastes schlegelii and Sebastiscus marmoratus

In order to understand the distribution of microsatellites in the whole genome of Sebastes schlegelii and Sebastiscus marmoratus, the MISA software was used to search and compare the microsatellite sequences of the whole S. schlegelii and S. marmoratus genomes. The results showed that the total length of the S. schlegelii genome sequence was 848 024 649 bp, the total number of sequences was 741 of which 635 sequences contained 534 272 microsatellite locus. The total length of microsatellite sequence was 14 151 681 bp with an average of one microsatellite loci per 1 587.25 bp, accounting for 1.67 % of the genome. There were 584 sequences containing more than one microsatellite locus, accounting for 91.97 % of the microsatellite locus sequences. 51 sequences contained one microsatellite locus, accounting for 8.03 % of the sequences containing microsatellite loci. The ratios of different repeat types of microsatellites were di-nucleotide (46.37%) > mono-nucleotide (30.97%) > tri-nucleotide (15.42%) > tetra-nucleotide (5.7%) > penta-nucleotide (1.19%) > hexa-nucleotide (0.35%) by size. The total length of the S. marmoratus genome sequence was 795 691 141 bp, and the total number of sequences was 90. Among them, 77 sequences contained 571 370 microsatellite locus. The total length of microsatellite sequence was 15 854 826 bp with an average of one microsatellite locus per 1 392.60 bp, accounting for 1.99 % of the the genome total length. There were 74 sequences containing more than one microsatellite locus, accounting for 96.10 % of the microsatellite locus sequences. 3 sequences contained one microsatellite locus, accounting for 3.70 % of the sequences containing microsatellite loci. The ratios of different repeat types of microsatellites were di-nucleotide (47.63%) > mono-nucleotide (32.90%) > tri-nucleotide (13.63%) > tetra-nucleotide (4.26%) > penta-nucleotide (1.04%) > hexa-nucleotide (0.53%) by size. Studies have shown that the microsatellites of different repeat types of S. schlegelii and S. marmoratus have the same performance. With the increase of the amplification length of microsatellite sequences, the frequency of nucleotides in the two fish species showed a gradual downward trend. This study was based on the comparison of the distribution of microsatellites in the whole genome of S. schlegelii and S. marmoratus, which provids a basis for the future research on microsatellite marker screening, genetic analysis and molecular breeding of these two kinds of fish.