Altering Fibroin Heavy
Chain Gene of Silkworm Bombyx mori by
Homologous Recombination
ZHAO Yun, CHEN Xiu1, PENG Wei-Ping1,
DONG Liang, HUANG Jun-Ting1, LU Chang-De*
( Institute of Biochemistry and Cell Biology,Shanghai Institutes for
Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China；1The Sericultural Research
Institute,Chinese Academy of Agricultural Sciences,Zhenjiang 212018,China )
Abstract A gene
unit, which encoded fibroin-like peptide, was synthesized and constructed. The
unit was multimerized to about 2 400 bp using BamHI and BglII
at each end of the unit, then was fused with gfp reporter gene. The
fusion gene, flanked by the 5′and 3′sequence of the fibroin heavy chain gene of
silkworm Bombyx mori, was transferred into the eggs of silkworm by
electroporation. After the silkworms developed and spinned silk, 73 out of
about 5 400 cocoons were brighter than normal ones under UV light. The protein
extracted from the brighter cocoon could react with the GFP polyclonal
antibodies. Genomic DNA from these silkworms and their progenies were analyzed.
The integration of gfp gene into genomic DNA of silkworm and the
occurrence of expected homologous recombination event had been proved by
Southern hybridization. It was shown that gfp-fibroin like fusion gene
had integrated into the genomic DNA of silkworm by homologous recombination and
the phenotype of “brighter cocoon” could be used to select transgenic silkworms.
Key words silkworm(Bombyx mori)； GFP； synthetic fibroin like gene；transgenic；homologous recombination
*Corresponding author：Tel,86-21-64374430-234；Fax,86-21-64338357；e-mail,[email protected]