The major advance during the past year was the identification of ligan
ds for two of the previously known position-specific integrins in Dros
ophila. At the same time, two new Drosophila integrin subunits (one al
pha and one beta) were discovered, and significant progress was made o
n developmental genetic analyses of integrin functions, shedding light
on the roles of integrins in Drosophila development.