Title:Immunological Function of the Antibacterial Peptide Attacin-Like in the Chinese Oak Silkworm, Antheraea pernyi
Volume: 27
Issue: 10
Author(s): Qingqing Li, Jiawei Zhang, Yu Sun, Lei Wang, Cen Qian, Guoqing Wei, Baojian Zhu*Chaoliang Liu*
Affiliation:
- College of Life Sciences, Anhui Agricultural University, Hefei 230036,China
- College of Life Sciences, Anhui Agricultural University, Hefei 230036,China
Keywords:
Antimicrobial peptides, innate immunity, Antheraea pernyi, attacin, E. coli, Nuclear Polyhedrosis Virus.
Abstract:
Background: Antibacterial peptides play important roles in the innate immune system
of insects and are divided into four categories according to their structures. Although many antibacterial
peptides have been reported in lepidopteran insects, the roles of an attacin-like gene in immune
response of Antheraea pernyi remain unclear.
Objective: In this study, the cloning and immunological functions of an attacin-like gene from Antheraea
pernyi were investigated.
Methods: The open reading frame of Ap-attacin-like gene was cloned by PCR using the specific
primers and then was ligated to the pET-32a vector to construct the recombinant plasmids Ap-attacin-
like-pET-32a. The recombinant Ap-attacin-like protein was expressed in E. coli (BL21 DE3)
cells and purified by Ni-NTA affinity chromatography. The expression patterns of Ap-attacin-like
in different tissues or under microorganism challenges were investigated by real-time PCR and
western blotting. Finally, agar well diffusion assay was performed to determine the antimicrobial
activity of the recombinant Ap-attacin-like proteins based on the inhibition rate.
Results: The expression level of Ap-attacin-like was highest in the fat body compared with the
other examined tissues. The expression of Ap-attacin-like in the fat body was significantly elevated
after E. coli, Beauveria bassiana, Micrococcus luteus or Nuclear Polyhedrosis Virus challenges. In
addition, the recombinant Ap-attacin-like proteins had obvious antibacterial activity against E. coli.
Conclusion: Ap-attacin-like was highly expressed in immune-related tissues and its expression level
was significantly induced by different microorganism challenges, suggesting that Ap-attacin-like
participated in the innate immunity of A. pernyi.
