Contributes to Reproductive Diapause by Regulating Lipid Storage and Survival of (Linnaeus).

Cathepsin L protease, which belongs to the papain-like cysteine proteases family, is an important player in many physiological and pathological processes. However, little was known about the role of in ladybird beetles ( Linnaeus) during diapause. Here, we analyzed the characteristics of () in the females of and its role during the diapause of the ladybeetle. was cloned and identified from beetle specimens by rapid amplification of cDNA-ends (RACE). The cDNA sequence of was 971 bp in length, including an 843 bp open reading frame encoding a protein of 280 amino acids. It was identified as the group by phylogenetic analysis. Knockdown of by RNA interference led to decreased expression levels of fatty acid synthase 2 (fas 2) genes and suppressed lipid accumulation. Furthermore, silencing the gene distinctly reduced diapause-related features and the survival of female under diapause-inducing conditions. The results suggested that the gene was involved in fatty acid biosynthesis and played a crucial role in the survival of adult during the diapause preparation stage.