Abstract
A minor chorion protein (called s70) with an approximate molecular weight of 70,000 D has been characterized in Drosophila melanogaster. The Staket geographic strain was found to carry an electrophoretic variant of this eggshell component and was used to determine the chromosomal location of the s70 gene. Our results establish a new locus for a chorion gene near yellow on the X chromosome and represent the first mapping of a quantitatively minor eggshell protein.
