Abstract: 【Abstract】  The genomic DNA was extracted from Simulium quinquestriatum （Sq） and its COⅠ gene was amplified by PCR. The PCR product was purified and cloned into plasmid pMD18-T vector. The recombinant plasmid was transformed into Escherichia coli DH5α and then identified by digestion with restriction enzyme and PCR amplification. The amplified frac-tions （1 621 bp） included complete COⅠ gene （1 542 bp, GenBank accession number： DQ534949）， 5′ tRNA-Tyr and 3′ tRNA-Leu partial fraction. The COⅠ gene sequence had a high identity （99%） with that of S. quinquestriatum （GenBank accession number： AY251520）. Bioinformatics analysis showed that the Sq-COⅠopen reading frame encoded a 513-amino acid protein with Mr 5 565, pI 5.84. Structural prediction showed this protein possessed a conservative domain of COⅠ gene.

Key words: Simulium quinquestriatum, COⅠ, Clone, Bioinformatics