Wj. Wolfgang et al., ACTIVATION OF PROTEIN-KINASE A-INDEPENDENT PATHWAYS BY GS-ALPHA IN DROSOPHILA, Proceedings of the National Academy of Sciences of the United Statesof America, 93(25), 1996, pp. 14542-14547
One of the best-described transmembrane signal transduction mechanisms
is based on receptor activation of the alpha subunit of the heterotri
meric G protein G(s), leading to stimulation of adenylyl cyclase and t
he production of cAMP. Intracellular cAMP is then thought to mediate i
ts effects largely, if not entirely, by activation of protein kinase A
and the subsequent phosphorylation of substrates which in turn contro
l diverse cellular phenomena, In this report we demonstrate, by two di
fferent methods, that reduction or elimination of protein kinase A act
ivity had no effect on phenotypes generated by activation of G(s) alph
a pathways in Drosophila wing epithelial cells, These genetic studies
show that the G(s) alpha pathway mediates its primary effects by a nov
el pathway in differentiating wing epithelial cells. This novel pathwa
y may in part be responsible for some of the complex, cell-specific re
sponses observed following activation of this pathway in different cel
l types.