Silkworm expression system as a platform technology in life science

Abstract

Many recombinant proteins have been successfully produced in silkworm larvae or pupae and used for academic and industrial purposes. Several recombinant proteins produced by silkworms have already been commercialized. However, construction of a recombinant baculovirus containing a gene of interest requires tedious and troublesome steps and takes a long time (3–6 months). The recent development of a bacmid, Escherichia coli and Bombyx mori shuttle vector, has eliminated the conventional tedious procedures required to identify and isolate recombinant viruses. Several technical improvements, including a cysteine protease or chitinase deletion bacmid and chaperone-assisted expression and coexpression, have led to significantly increased protein yields and reduced costs for large-scale production. Terminal N-acetyl glucosamine and galactose residues were found in the N-glycan structures produced by silkworms, which are different from those generated by insect cells. Genomic elucidation of silkworm has opened a new chapter in utilization of silkworm. Transgenic silkworm technology provides a stable production of recombinant protein. Baculovirus surface display expression is one of the low-cost approaches toward silkworm larvae-derived recombinant subunit vaccines. The expression of pharmaceutically relevant proteins, including cell/viral surface proteins, membrane proteins, and guanine nucleotide-binding protein (G protein) coupled receptors, using silkworm larvae or cocoons has become very attractive. Silkworm biotechnology is an innovative and easy approach to achieve high protein expression levels and is a very promising platform technology in the field of life science. Like the “Silkroad,” we expect that the “Bioroad” from Asia to Europe will be established by the silkworm expression system.

Transgene-based, female-specific lethality system for genetic sexing of the silkworm, Bombyx mori

“…Thus, novel approaches are desired to improve modern silkworm breeding. In recent years, advances in B. mori genetic manipulation, notably genetic transformation, have been successfully established and applied extensively in gene function analysis and the production of bioreactors (1,(4)(5)(6)(7). These technologies provide a potential basis for improvements in sericulture including the development of a male-only rearing system.…”

Silkworms transformed with chimeric silkworm/spider silk genes spin composite silk fibers with improved mechanical properties

“…Although silkworms are not recognized as a major recombinant protein production platform (21)(22)(23), they might be the perfect host for spider silk fiber production because transgenic silkworms can be efficiently produced using piggyBac vectors (24)(25)(26), recombinant protein production can be targeted to the silk gland with tissuespecific promoters (27)(28)(29)(30)(31)(32), and the silk gland is naturally equipped to assemble silk proteins into fibers (33). One caveat is that silkworms produce endogenous silk proteins.…”

Functional Virus-Like Particles Production Using Silkworm and Their Application in Life Science

“…Two decades ago, protein expression in silkworms was difficult and time-consuming, because of cultured insect cells were mainly used as baculovirus hosts for protein production. However, Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid (a baculovirus shuttle vector), which can be replicated in E. coli and generate the recombinant baculovirus DNA by site-specific transposition in E.coli, has been developed [68] and many reports on recombinant protein expression in silkworms are being published [69].…”