Recombinant Drosophila melanogaster Cullin homolog 1 (lin19), partial

Core component of multiple SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complexes which mediate the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. In the SCF complex, serves as a rigid scaffold that organizes the SKP1-F-box protein and RBX1 subunits. May contribute to catalysis through positioning of the substrate and the ubiquitin-conjugating enzyme. During early metamorphosis, part of the SCF-slmb complex that negatively regulates the InR/PI3K/TOR pathway to activate the pruning of unnecessary larval ddaC dendrites and mushroom body axons. The SCF-slmb complex also regulates asymmetrical division of neuroblasts and inhibits ectopic neuroblast formation partly through SAK and Akt1. Also part of an SCF complex required for caspase activation during sperm differentiation. Necessary for auditory transduction: plays a role in Johnston's organ organization by acting in the regulation of zip and ck function in scolopidial apical attachment. May function by acting in a Ubr3-mediated pathway that negatively regulates the ubiquitination of zip, consequently affecting its interaction with ck.