利用MISA(MicroSAtelite)软件对测序得到的蒙药冷蒿转录组序列143 700条跨叠群(contigs)进行简单重复序列(SSR)位点的挖掘,发现3 614条序列含有3 753个SSR位点,发生频率为2.51%,共有122种重复基元,平均每18.46 kb出现1个SSR位点.冷蒿转录组序列的SSR主要集中在三核苷酸重复(56.12%),其次是二核苷酸重复(31.60%).AC/TG、AT/TA、CA/GT、AAT/TTA和AAC/TTG是二核苷酸、三核苷酸中的优势重复基元.冷蒿转录组SSR以5~12次重复为主,基序长度主要集中于12~36 bp.冷蒿转录组共注释43 415个contigs,其中578个SSRs位于编码区,主要以三核苷酸重复为主(397,68.69%).从分子水平和生物信息学角度介绍了蒙药冷蒿转录组SSR信息的开发利用,其出现频率高、重复类型丰富,将为冷蒿的分子标记辅助育种、遗传多样性分析、遗传图谱构建和功能基因挖掘提供了候选序列.
MISA (MicroSAtelite) software was employed to screen SSRs in 68 787 contigs of Swertia mussotii transcriptome sequences. 5 610 SSRs were distributed in 5 099 contigs which accounted for 7.41% of 68 787 contigs. There are 220 kinds of SSR motifs existing in S. mussotii transcriptome. On average, SSRs occurred every 12.60 kb in length. In the SSRs, the tri-nucleotide repeat motif was the most abundant (45.99%), followed by the di-nucleotide (41.62%). AT/TA and AAT/TTA were the main types of motif in di-, tri-nucleotide repeats. The repeat numbers of SSRs which from S. mussotii transcriptome SSRs were mainly from 5 to 10 and motif length of them mostly ranged from 12 bp to 30 bp. A total of 30 651 contigs were annotated, and only 1 447 SSRs were occurred in protein-coding regions. In the six repeat motifs, tri-nucleotide repeats were the most abundant in coding regions (928). There are abundant SSRs in S. mussotii transcriptome with high frequency and various types, indicating their usefulness in theory. This research may lay the foundation for designing the targeted SSR primers and developing SSR molecular markers by mining the information of SSRs loci in S. mussotii transcriptome sequences data.