Characterization of the RACK1 gene of Aips cerana cerana and its role in adverse environmental stresses.

Abstract

Receptors for Activated C Kinase 1 (RACK1s) are a kind of multifunction scaffold protein that plays an important role in cell signal transductions and animal development. However, the function of RACK1 in the Chinese honeybee Apis cerana cerana is little known. Here, we isolated and identified a RACK1 gene from Apis cerana cerana, named AccRACK1. By bioinformatic analysis, we revealed a high nucleic acid homology between AccRACK1 and RACK1 of Apis cerana. RT-qPCR analyses demonstrated AccRACK1 was mostly expressed in 3rd instar larvae, darked-eyed pupae and adults (one and thirty days post-emergence), suggesting it might participate in the development of A. cerana cerana. Moreover, the expression of AccRACK1 was highest in the thorax, followed by the venom gland. Compared to the blank control group, AccRACK1 was induced by 24 and 44°C, HgCl2 and pesticides (paraquat, pyridaben and methomyl) but inhibited by 14°C, H2O2, UV light and cyhalothrin. Additionally, 0.05, 0.1, 1, 5 and 10mg/ml PPN (juvenile hormone analogue pyriproxyfen) could promote the expression of AccRACK1, with 1mg/ml showing the highest upregulation, suggesting it was regulated by hormones. Further study found that after knockdown of AccRACK1 by RNAi, the expression of the eukaryotic initiation factor 6 of A. cerana cerana (AcceIF6), an initiation factor regulating the initiation of translation, was inhibited, indicating AccRACK1 might affect cellular responses by translation. These findings, taken together, suggest AccRACK1 is involved in the development and responses to abiotic stresses of A. cerana cerana, and therefore, it may be of critical importance to the survival of A. cerana cerana.