D. Fambrough et al., THE CELL-SURFACE METALLOPROTEASE DISINTEGRIN KUZBANIAN IS REQUIRED FOR AXONAL EXTENSION IN DROSOPHILA, Proceedings of the National Academy of Sciences of the United Statesof America, 93(23), 1996, pp. 13233-13238
It has long been suspected that proteolytic activity associated with a
dvancing growth cones may be required for axon extension. We have isol
ated mutations in the kuzbanian (kuz) gene, which is expressed in the
nervous system and encodes a putative zinc metalloprotease with a disi
ntegrin domain. Drosophila embryos with loss-of-function mutations in
kuz have dramatic defects in the development of central nervous system
axon pathways, with many axons stalling and failing to extend through
the nerve cord. This phenotype is rescued by panneural expression of
kuz mRNA in the embryo. These results show that the Kuz metalloproteas
e is required for axon extension, suggesting a requirement for proteol
ytic activity at the growth cone surface.