Drosophila Introduction

Question 1

Which are the stages of drosophila’s development?

Answer 1

embryo
3 larval stages
prepupa
pupa
adult fly

Question 2

How do you create transgenic flies?

Answer 2

collect synchronized eggs before germ line cells are formed
wash, align on a slide, inject with DNA
let eggs develop into G0 adults
cross G0 to stock mutant for selection marker
screen F1 progeny for selection marker

Question 3

Describe the basic UAS/Gal4 system.

Answer 3

Gal4 under control of tissue specific enhancer

in specific tissues = expressed = binds to UAS and triggers expression of efector gene

Question 4

How can Gal4/UAS be refined?

Answer 4

Additional control for time expression by Gal80 which is temperature sensitive: as you transfer the cells to permissive temperature, Gal80 does not repress the Gal4:UAS and effector gene can be expressed

split-Gal4: DNA binding and transcription activation domain of Gal4 are separated (each under control of a different promoter) and only in cells where both are active, target gene is expressed

terniary split = combination of 2 split-Gal4 systems to refine expression pattern