Drosophila-raf acts to elaborate dorsoventral pattern in the ectoderm of developing embryos.
In the early Drosophila embryo the activity of the EGF-receptor (Egfr) is required to instruct cells to adopt a ventral neuroectodermal fate. Using a gain-of-function mutation we showed that D-raf acts to transmit this and other late-acting embryonic Egfr signals. A novel role for D-raf was also identified in lateral cell development using partial loss-of-function D-raf mutations. Thus, we provide evidence that zygotic D-raf acts to specify cell fates in two distinct pathways that generate dorsoventral pattern within the ectoderm. These functional requirements for D-raf activity occur subsequent to its maternal role in organizing the anterioposterior axis. The consequences of eliminating key D-raf regulatory domains and specific serine residues in the transmission of Egfr and lateral epidermal signals were also addressed here.
Radke
K
K
Signal Transduction Training Group, Department of Zoology and Genetics, Iowa State University, Ames, Iowa 50011, USA.
Johnson
K
K
Guo
R
R
Davidson
A
A
Ambrosio
L
L
D000818:Animals; D030801:Animals, Genetically Modified; D015153:Blotting, Western; D019070:Cell Lineage; D004330:Drosophila / Q000196:embryology* / Q000235:genetics*; D029721:Drosophila Proteins; D004475:Ectoderm / Q000378:metabolism / Q000502:physiology*; D004625:Embryo, Nonmammalian / Q000502:physiology*; D006720:Homozygote; D008957:Models, Genetic; D009154:Mutation; D010641:Phenotype; D020033:Protein Isoforms; D017434:Protein Structure, Tertiary; D019908:Proto-Oncogene Proteins c-raf / Q000235:genetics* / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D012694:Serine / Q000737:chemistry; D015398:Signal Transduction; D013997:Time Factors; D019076:Transgenes; D015053:Zygote / Q000378:metabolism
D029721:Drosophila Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D012694:Serine; D019908:Proto-Oncogene Proteins c-raf; C420924:Raf protein, Drosophila