Valeriya Zabelina
National Agriculture and Food Research Organization, Japan
Title: Standardization of products of biotechnological sericulture by parthenocloning and cryobanking of transgenic clonal silkworms
Biography
Biography: Valeriya Zabelina
Abstract
Current genetic engineering of the silkworm enables to produce new kinds of silk and to use silkworms as proteosynthetic
bioreactors for obtaining precious proteins. Nowadays a lot of target products derived from the silkworm are already
used in many areas of life from cosmetics through pharmacy, regenerative medicine to cosmonautics. The problem of
product standardization we propose to solve by easy and inexpensive decision – parthenocloning, which enables rapid
fixation of transformed genotypes and conservation of any unique man-made complexes. Parthenocloning is based on
exact copying of maternal genome and a single female initiates a clonal line with the same genetic and morphological
traits, which can be easily maintained without sexual reproduction as exclusively female populations. Such populations
exist already for more than 50 years as genetically stable females whose unfertilized eggs are induced to develop by
heat-shock treatment. This is the best time-tested evidence of genome stability. We constructed new non-diapausing
parthenogenetic strains and developed efficient injection method adapted for the eggs of parthenoclone. We showed
that transgenic silkworms could be obtained in high frequency and propagated as clonal populations. We obtained
successful transgenesis in a parthenoclone and inserted transgenes were faithfully transferred to successive generations.
We showed the possibility of cryopreservation of ovaries of transgenic clonal strains and obtained recovery as individuals
by ovary transplantation into female larvae, which opens door for cryobanking of any specific standardized genotypes
used for obtaining of precious target products.