In Drosophila, Gurken protein interacts specifically with:
Gurken protein is secreted EGF family ligand transported to perinuclear region, where extracellular domain binds Torpedo receptor, Drosophila EGFR homolog expressed on follicle cells. Torpedo activation triggers Ras-MAPK and Pointed cascade repressing Pipe dorsally. Pipe, Toll, and Easter function downstream in vitelline modification and proteolysis and do not interact directly with Gurken. Specificity of Gurken-Torpedo interaction ensures spatial restriction of dorsal follicle fate, establishing symmetry break by nuclear migration that positions Gurken signal, linking oocyte cytoskeleton pola
Ref: Alberts, Molecular Biology of the Cell, Chapter 22: Gurken binding Torpedo EGFR - oocyte nucleus migration and_PIPE repression.
