The grooveless gene encodes a single von Willebrand factor type C domain protein necessary for proper formation of the scutoscutellar sulcus in Drosophila melanogaster.

We show that disruption of the CG31997 gene on the fourth chromosome of Drosophila melanogaster by grooveless mutations results in loss of the scutoscutellar sulcus, the hinge-like region between the two major divisions of the fly thorax necessary for normal wing movement in flight. This gene belongs to a family of arthropod secreted proteins with a single von Willebrand factor type C domain, and our study expands the biological roles of these enigmatic proteins to include morphogenesis.