A notch-independent activity of suppressor of hairless is required for normal mechanoreceptor physiology.
Suppressor of Hairless [Su(H)]/Lag-1/RBP-Jkappa/CBF1 is the only known transducing transcription factor for Notch receptor signaling. Here, we show that Su(H) has three distinct functions in the development of external mechanosensory organs in Drosophila: Notch-dependent transcriptional activation and a novel auto-repression function, both of which direct cell fate decisions, and a novel auto-activation function required for normal socket cell differentiation. This third phase of activity, the first known Notch-independent activation function for Su(H) in development, depends on a cell type-specific autoregulatory enhancer that is active throughout adult life and is required for proper mechanoreception. These results establish a direct link between a broadly deployed cell signaling pathway and an essential physiological function of the nervous system.
Barolo
S
S
Division of Biology/CDB University of California, San Diego 92093, La Jolla, CA, USA.
Walker
R G
RG
Polyanovsky
A D
AD
Freschi
G
G
Keil
T
T
Posakony
J W
JW
D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D002454:Cell Differentiation; D004330:Drosophila / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology*; D029721:Drosophila Proteins; D004594:Electrophysiology; D004742:Enhancer Elements, Genetic / Q000235:genetics*; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins; D006651:Histocytochemistry; D017403:In Situ Hybridization; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008465:Mechanoreceptors / Q000502:physiology* / Q000648:ultrastructure; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D011679:Pupa / Q000378:metabolism / Q000648:ultrastructure; D051880:Receptors, Notch; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013696:Temperature; D014158:Transcription, Genetic / Q000235:genetics*
D029721:Drosophila Proteins; D019476:Insect Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008164:Luminescent Proteins; D008565:Membrane Proteins; C497759:N protein, Drosophila; D051880:Receptors, Notch; D012097:Repressor Proteins; C088731:Su(H) protein, Drosophila; C064045:delta protein; D049452:Green Fluorescent Proteins