Expression of human papillomavirus 6b L1 protein in silkworm larvae and enhanced green fluorescent protein displaying on its virus-like particles

Muthukutty Palaniyandi,Enoch Y Park,Tatsuya Kato

doi:10.1186/2193-1801-1-29

Muthukutty Palaniyandi, Enoch Y Park + Show 1 more

Open Access

https://doi.org/10.1186/2193-1801-1-29

Copy DOI

Journal: SpringerPlus	Publication Date: Oct 4, 2012
Citations: 17	License type: cc-by

Affiliation: Shizuoka University

Abstract

Human papillomavirus (HPV) 6b L1 capsid protein was expressed using the Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid expression system in silkworm larvae. Two constructs, full-length L1 (500 a.a) and C-terminal-deleted short L1 (479 a.a), and three PCR-manipulated antigenic loops at amino acids 55–56, 174–175, and 348–349 regions were incorporated with whole enhanced green fluorescent protein (EGFP). Expressed in full, short L1 proteins and variants were purified in heparin affinity column chromatography and confirmed by SDS-PAGE and western blot. The presence of self-assembled virus-like particles (VLPs) and EGFP incorporation on the surface of VLPs were confirmed by the observation of transmission electron and immunoelectron microscopies, respectively. HPV 6b L1 major capsid protein was successfully expressed in silkworm, and effective manipulation on the antigenic regions showed the path to versatile vaccine development based on HPV L1-VLPs.

Highlights

Virus-like particles (VLPs) are empty virus particles, which lack virus-derived genome DNA or RNA, and composed of virus-capsid or matrix proteins
Human papillomavirus (HPV) 6b L1 protein was expressed in silkworm larvae, and HPV 6b L1VLPs were purified from the fat body of silkworms
Expression of HPV 6b L1 protein and its short variant in silkworm larvae HPV 6b L1 protein has a basic domain at its C-terminus, which can bind to genomic DNA and pack into virus particles (Li et al 1997; Touze et al 2000)

Summary

Introduction

Virus-like particles (VLPs) are empty virus particles, which lack virus-derived genome DNA or RNA, and composed of virus-capsid or matrix proteins. A nonenveloped virus, VLPs are mainly composed of viruscapsid proteins, which can be self-assembled both in vitro and in vivo. HPV L1 protein can be self-assembled as a VLP when this protein is expressed in various expression systems (Trus et al 1997). To display this whole protein on the surface of HPV 6b L1-VLPs, EGFP, as a model of a whole full-length protein, was inserted into BC, EF, and HI loop domains (Bishop et al 2007; Chen et al 2000) of HPV 6b L1 protein. EGFP-incorporated HPV-VLPs were analyzed and discussed targeting for using alternative vaccine candidate

Methods

Results

Conclusion