Identification and Expression Analysis of a cDNA Encoding Cyclophilin A from Gryllus bimaculatus (Orthoptera: Gryllidae)

Abstract

Cyclophilin A (CypA), a cytosolic binding protein of cyclosporine A, is an immunosuppressive drug. In this study, CypA cDNA was cloned from the two-spotted cricket Gryllus bimaculatus (gCypA). The protein encoded by gCypA comprises 165 amino acids with a molecular mass of 19.23 kDa and an isoelectric point of 9.38 and possesses three N-glycosylation sites and 17 phosphorylation sites. The secondary and tertiary structures of gCypA were identified, and homology analysis revealed that it shares around 73%-81% sequence identities with other CypA proteins. When the researchers analyzed the expression levels of gCypA mRNA in various tissues, they found that the foregut exhibited nearly the same expression level as that of the dorsal longitudinal flight muscle (the control). However, gCypA mRNA expression in the fat body, Malpighian tubes, and midgut was less than half of that in the dorsal longitudinal flight muscle. Under endoplasmic reticulum stress conditions, gCypA mRNA expression was highest in Malpighian tubules (about two times higher than the expression in the control). Under starvation conditions, gCypA mRNA expression increased to three times that of the dorsal longitudinal flight muscle 6 days after starvation. Nonetheless, its expression levels decreased in Malpighian tubules under all starvation conditions. This study provides insights into the physiological role of gCypA in G. bimaculatus.