Cloning and characterization of myosin regulatory light chain (MRLC) gene from Culex pipiens pallens.

Myosin regulatory light chain (MRLC) (GenBank accession no. DQ140391) was cloned from Culex pipiens pallens. An open reading frame (ORF) of 630 bps was found to encode a putative 210 amino acids protein which shows 73% similarity with myosin regulatory light chain of Gryllotalpa orientalis. Real-time quantitative PCR analysis demonstrated that the transcription level of MRLC in deltamethrin-resistant strain (DR-strain) was 4.08-fold higher than in deltamethrin-susceptible strain (DS-strain) of C. pipiens pallens. Over-expression of MRLC in Aedes albopictus C6/36 cells conferred protection against deltamethrin based on tritiated methyl tritiated thymidine ((3)H-TdR) incorporation assay. These results indicate that MRLC may be a potential cause of deltamethrin resistance in C. pipiens pallens.