Objective To reveal the sequence characteristics and expression profiles of CD36 homolog genes, sensory neuron membrane proteins (SNMPs) and class b scavenger receptors (SRb) in Orthosia songi Chen et Zhang.

Method Specific primers were used to clone the SNMP and SRb genes. The protein encoded by these genes were constructed by homo-modeling, and the gene expression profiles were determined by quantitative fluorescent real-time PCR.

Result Three CD36 homolog genes (OsonSNMP1, OsonSNMP2 and OsonSRb1) were identified from O. songi. The proteins encoded by these genes consisted of two transmembrane domains and an extracellular domain. The extracellular domain contained an antiparallel β-barrel core and a hydrophobic domain near the top. OsonSNMP1 was mainly expressed in the antennae and wings of male and female moth, and the expression level in male antennae was significantly higher than that in other tissues. OsonSNMP2 was discriminatorily expressed in male and female antennae and female wings, and its expression level in female antennae was significantly higher than that in other tissues. OsonSRb1 were specifically expressed in the antennae and mouthparts of male and female.

Conclusion The proteins encoded by OsonSNMP1, OsonSNMP2 and OsonSRb1 have similar structures with CD36 receptors in vertebrates. Their expression profiles highly associated with olfactory organs indicate the potential roles in olfactory systems. These results provide experimental data for further study on the olfactory function of CD36 homolog genes in Orthosia songi.