Shavenbaby information

The shavenbaby (svb) or ovo gene encodes a transcription factor in Drosophila responsible for inducing cells to become hair-like projections called trichomes or microtrichia.^[1][2] Many of the major developmental signaling pathways converge at the shavenbaby locus, which then regulates over 150 downstream target genes.^[3] The "hourglass" shape of this gene regulatory network makes shavenbaby the master regulator of trichome formation.^[4][2] The unique setup of the gene regulatory network made trichomes an excellent readout to identify important developmental genes during the forward genetics Heidelberg Screen.^[5] Additionally, shavenbaby is considered to be an "evolutionary hotspot",^[6] and experiments have shown that changes in this gene cause the loss of dorsal cuticular hairs in Drosophila sechellia larvae.^[2]

Trichomes likely serve a variety of purposes. In larvae, trichomes likely help with larval locomotion. By alternating between bands of trichomes and naked cuticle, larvae can tread across different surfaces. Additionally, trichomes may contribute to hydrophobicity and even stabilize adult flight.^[7]