Article

3xP3-EGFP marker facilitates screening for transgenic silkworm Bombyx mori L. from the embryonic stage onwards.

Unité Nationale Séricicole, INRA, 25 quai J.J. Rousseau, 69350, La Mulatiere, France.
Insect Biochemistry and Molecular Biology (impact factor: 3.25). 04/2002; 32(3):247-53.
Source: PubMed

ABSTRACT Transgenesis was recently achieved in Bombyx mori L., but it has proved difficult and time-consuming to screen the numerous progeny to identify the transgenic individuals. As the 3xP3-EGFP marker has been shown to be a suitable universal marker for transgenic insects (Nature 402 (1999) 370), we evaluated its use for embryonic-stage screening for B. mori L. germline transformation. Using the piggyBac-derived vector pBac[3xP3-EGFPaf], we were able to isolate four transgenic individuals from about 120,000 embryos (560 broods). The screening was straightforward due to EGFP production in the G1 embryonic stemmata, which was visible through the translucent egg chorion. EGFP was produced in the stemmata and central and peripheral nervous systems from the fifth day of embryonic development. It persisted at high levels in the stemmata throughout the larval stage, and was also present in the compound eyes and nervous tissues of the pupae and the compound eyes of the moths.

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Keywords

3xP3-EGFP marker
 
B. mori L. germline transformation
 
Bombyx mori L
 
central
 
compound eyes
 
difficult
 
embryonic development
 
embryonic-stage screening
 
G1 embryonic stemmata
 
larval stage
 
nervous tissues
 
peripheral nervous systems
 
piggyBac-derived vector pBac[3xP3-EGFPaf]
 
screening
 
suitable universal marker
 
Transgenesis
 
transgenic individuals
 
transgenic insects
 
translucent egg chorion
 
visible
 

J L Thomas