title: Reciprocal changes in expression of the receptor lin-12 and its ligand lag-2 prior to commitment in a C. elegans cell fate decision.
abstract: During development of the C. elegans hermaphrodite gonad, two cells interact with each other, so that one chooses to become the anchor cell (AC) and the other becomes a ventral uterine precursor cell (VU). This interaction is mediated by the receptor LIN-12 and its apparent ligand LAG-2. We show that initially lin-12 and lag-2 are expressed in both cells, but prior to commitment, the expression patterns change in a reciprocal manner, so that lin-12 expression becomes restricted to the presumptive VU and lag-2 expression becomes restricted to the presumptive AC. In addition, lin-12 activity promotes expression of lin-12 and represses expression of lag-2. Furthermore, we show that positive autoregulation of lin-12 transcription in the presumptive VU is mediated by a cis-acting 5' regulatory sequence and is necessary to specify the VU fate. Our results suggest that transcriptional control is a component of the feedback mechanism involved in specifying the AC and VU fates.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Columbia University College of Physicians and Surgeons, New York, New York 10032.
authors.forename: H A
authors.initials: HA
authors.lastname: Wilkinson
authors.forename: K
authors.initials: K
authors.lastname: Fitzgerald
authors.forename: I
authors.initials: I
authors.lastname: Greenwald
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000166:cytology* / Q000235:genetics / Q000254:growth & development; D029742:Caenorhabditis elegans Proteins; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D006066:Gonads / Q000166:cytology / Q000254:growth & development; D015801:Helminth Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D051880:Receptors, Notch; D015398:Signal Transduction / Q000502:physiology; D014158:Transcription, Genetic
chemical_list: D029742:Caenorhabditis elegans Proteins; D015801:Helminth Proteins; C082460:Lin-12 protein, C elegans; D008565:Membrane Proteins; D051880:Receptors, Notch; C086488:lag-2 protein, C elegans