V. Mach et al., THE DROSOPHILA FORK HEAD FACTOR DIRECTLY CONTROLS LARVAL SALIVARY-GLAND-SPECIFIC EXPRESSION OF THE GLUE PROTEIN GENE SGS3, Nucleic acids research, 24(12), 1996, pp. 2387-2394
The Drosophila Fork head protein participates in salivary gland format
ion, since salivary glands are missing in fork head embryos, Here we s
how that the fork head encoded protein binds to an upstream regulatory
region of the larval salivary gland glue protein gene Sgs3. Mobility
shift assay in the presence of an anti-fork head antibody demonstrated
that the Fork head factor interacts with the TGTTTGC box shown to be
involved in tissue-specific Sgs3 expression. Experiments employing a s
et of oligonucleotide competitors revealed that Fork head binding was
prevented by the same single base substitutions that were previously s
hown to interfere with the TGTTTGC element function in vivo. Furthermo
re, the anti-fork head antibody bound to >60 sites of polytene chromos
omes, including the puffs of all Sgs genes and Fork head protein was d
etected in the nuclei of salivary glands of larvae of all examined sta
ges, These data provide experimental evidence for the hypothesis that
the protein encoded by the fork head gene is required initially for sa
livary gland formation and is utilized subsequently in the control of
larval genes specifically expressed in this organ.