twit [Search on AGR]
Drosophila melanogaster target of wit (twit) encodes a GPI-anchored membrane ligand of the Ly6 family that participates in retrograde signalling as a downstream target of the BMP pathway receptor encoded by wit. It acts in neurons, regulating spontaneous neurotransmitter release during the maturation of larval neuromuscular junctions.
wit [Search on AGR]
Drosophila melanogaster wishful thinking (wit) encodes a BMP Type II Receptor that, upon binding of the ligand encoded by gbb, makes a complex with either tkv or sax encoding BMP type I receptors. This complex initiates phosphorylation and nuclear translocation of the transcription factor encoded by Mad. wit product controls synaptic homeostasis and neurotransmission at the neuromusclular junction during larval development. It also regulates the peptidergic phenotype of several neurosecretory cells.
babo [Search on AGR]
Drosophila melanogaster baboon (babo) encodes the type I receptor for the activin-like ligands encoded by daw, Actbeta and myo. There are three isoforms of the product of babo that differ only in their extracellular domain likely resulting in different ligand binding specificity. It can form a complex with the type II receptors put or wit in the presence of an activin like ligand. This results in the transcriptional regulation of activin responsive genes.