Intrinsic activity of the Lin-12 and Notch intracellular domains in vivo

Howard Hughes Medical Institute, Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, New York 10032.
Cell (Impact Factor: 32.24). 08/1993; 74(2):331-45. DOI: 10.1016/0092-8674(93)90424-O
Source: PubMed


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.

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    • "RESULTS N signaling is sufficient to induce cap cell formation As N signaling plays an important role in regulating specification of many different cell types (Artavanis-Tsakonas et al., 1999; Lai, 2004), we sought to test whether N signaling regulates the formation of cap cells in the Drosophila ovary by manipulating the signaling pathway in somatic cells of developing female gonads using the GAL4-UAS system (Brand and Perrimon, 1993). Ectopic expression of a truncated N intracellular domain (N int ) or its ligand Delta (Dl) can activate N signaling in ectopic locations (Struhl et al., 1993), and the c587-gal4 driver can drive a UAS-GFP specifically in most, but not all, of the somatic cells of developing female gonads (Zhu and Xie, 2003) (Fig. 1B,B). A hedgehog (hh)-lacZ line (the bacterial lacZ gene inserted in the hh gene) is highly expressed in five to seven cap cells and eight to ten TF cells (Forbes et al., 1996a) (Fig. 1C). "

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    • "The canonical Notch signaling involves ligand-dependent processing, release, and translocation into the nucleus of the Notch intracellular domain (Nintra/NICD) to activate target genes [31]–[33]. Up-regulation of canonical Notch signaling is associated with the development of the anti-neurogenic phenotype [34]–[36]. The heph embryos manifest the anti-neurogenic phenotype due to increased canonical Notch signaling [22]. "
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    PLoS ONE 07/2014; 9(7):e98585. DOI:10.1371/journal.pone.0098585 · 3.23 Impact Factor
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    • "The same procedure was used for flies expressing GAL4/UAS combinations to knockdown genes using RNAi or to express reporter lines. The following Drosophila stocks were used: Gbe-Su(H)-lacZ (NRE-lacZ) (Furriols and Bray, 2001), Gbe-Su(H)-Gal4 (NRE-Gal4) (Zeng et al., 2010), FRT82B dakt 1 (Rintelen et al., 2001), FRT82B inr 31 (Brogiolo et al., 2001), UAS-dinr RNAi RII2 (a gift from R. Ueda, NIG, Mishima, Japan), UAS-N icd (Struhl et al., 1993), UAS hFOXO3a-TM (Jünger et al., 2003), FRT82B dp110 1C1 [obtained from Hugo Stocker (Willecke et al., 2011)], UAS cut 5 (Krupp et al., 2005), foxo Δ94 and FRT82B foxo Δ94 (Slack et al., 2011), FRT82B inr ex15 (Song et al., 2003) and string-lacZ ( p[w+ stgB R6.4]) (a gift from B. Edgar, ZMBH, Heidelberg). Tub-gal80 ts , UAS-rpr, UAS-dinr del , UAS-cut RNAi TRIP29625, UAS-N RNAi TRIP28981, UAS-p60(PI3K DN ), fizzy related-lacZ and FRT82B strains were from the Bloomington Stock Center. "
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