Intrinsic activity of the Lin-12 and Notch intracellular domains in vivo.
The lin-12 gene of C. elegans and the Notch gene of D. melanogaster encode structurally related transmembrane proteins that mediate intercellular signaling. We show that truncated forms of these proteins consisting of only the intracellular domains cause cell fate transformations associated with constitutive activity in their respective organisms. This activity does not depend on endogenous gene function. Our results indicate that the intracellular domains of Lin-12 and Notch have intrinsic activity and that the principal role of the extracellular domains in the intact proteins is to regulate this activity. Our results also suggest that equivalent truncated forms of lin-12/Notch family members in vertebrates, including known oncogenes, are similarly active.
Struhl
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G
Howard Hughes Medical Institute, Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, New York 10032.
Fitzgerald
K
K
Greenwald
I
I
D001003:Anal Canal / Q000196:embryology; D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics; D029742:Caenorhabditis elegans Proteins; D016764:Cell Polarity / Q000235:genetics; D003080:Cold Temperature; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics; D004817:Epidermis / Q000196:embryology; D015801:Helminth Proteins / Q000235:genetics*; D006358:Hot Temperature; D007301:Insect Hormones / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics*; D009417:Nerve Tissue / Q000196:embryology; D051880:Receptors, Notch; D017384:Sequence Deletion; D013329:Structure-Activity Relationship
D029742:Caenorhabditis elegans Proteins; D029721:Drosophila Proteins; D015801:Helminth Proteins; D007301:Insect Hormones; C082460:Lin-12 protein, C elegans; D008565:Membrane Proteins; C497759:N protein, Drosophila; D051880:Receptors, Notch