The multicolored Asian ladybeetle Harmonia axyridis is characterized by polymorphism of the elytral pattern. Melanization in Harmonia axyridis is crucial for their elytral coloration, but the molecular mechanisms are not fully understood in this species. Tyrosine hydroxylase (TH) and dopa decarboxylase (DDC), two key enzymes in the melanin pathway, convert tyrosine and dopa into dopa and dopamine, respectively. In this study, it was to determine the role of TH and DDC of Harmonia axyridis (HaTH and HaDDC) in body and wing pigmentaion produced via melanin pathway. The cDNA sequences of HaTH and HaDDC were cloned to perform RNAi-based functional analysis. Injected dsRNA to the 4th larvae caused knockdown of target genes, and it was verified by quantative realtime PCR. Both TH and DDC RNAi adult show loss of black pigmentation in their body and wing pigmentaion. These results is expected to be helpful to investigate polymorphism by melanin pigment in Harmonia axyridis.

• Younghwan Kwak(Department of Applied Biology, College of Agriculture and Life sciences, Chungnam National University)
• Heon Yoon(Department of Applied Biology, College of Agriculture and Life sciences, Chungnam National University)
• Seo Yeong Bae(Department of Applied Biology, College of Agriculture and Life sciences, Chungnam National University)
• Yong Man Yu(Department of Applied Biology, College of Agriculture and Life sciences, Chungnam National University)
• Young Nam Yoon(Department of Applied Biology, College of Agriculture and Life sciences, Chungnam National University)