Localization of Sequences Regulating Drosophila Chorion Gene Amplification and Expression

Abstract

Recently there has been considerable progress in determining the structure of numerous eukaryotic genes. Sequences important for the initiation, processing, and termination of gene transcripts have been mapped in detail, and the biochemical characterization of regulatory factors is progressing rapidly. The elucidation of control mechanisms acting on genes within multicellular organisms during development has proved to be a more difficult problem, however. Experimental systems that unambiguously reproduce developmental controls are rare. During the last 3 years, the development of gene transfer methods for several higher organisms has facilitated a purely genetic approach to this problem. Modified genes are introduced into the germ line of multicellular organisms such as Drosophila, mouse, or tobacco, where their activity can be studied during the development of succeeding generations. The chief limitation with such experiments has now become simply the time that elapses during the generations required to establish sufficient numbers of genetically uniform transformed...