fringe and Notch specify polar cell fate during Drosophila oogenesis.
fringe encodes a glycosyltransferase that modulates the ability of the Notch receptor to be activated by its ligands. We describe studies of fringe function during early stages of Drosophila oogenesis. Animals mutant for hypomorphic alleles of fringe contain follicles with an incorrect number of germline cells, which are separated by abnormally long and disorganized stalks. Analysis of clones of somatic cells mutant for a null allele of fringe localizes the requirement for fringe in follicle formation to the polar cells, and demonstrates that fringe is required for polar cell fate. Clones of cells mutant for Notch also lack polar cells and the requirement for Notch in follicle formation appears to map to the polar cells. Ectopic expression of fringe or of an activated form of Notch can generate an extra polar cell. Our results indicate that fringe plays a key role in positioning Notch activation during early oogenesis, and establish a function for the polar cells in separating germline cysts into individual follicles.
Grammont
M
M
Howard Hughes Medical Institute, Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers The State University of New Jersey, Piscataway, NJ 08854, USA.
Irvine
K D
KD
D000818:Animals; D002454:Cell Differentiation; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D016296:Mutagenesis; D017351:N-Acetylglucosaminyltransferases; D009866:Oogenesis / Q000502:physiology*; D006080:Ovarian Follicle / Q000166:cytology / Q000378:metabolism; D010053:Ovary / Q000166:cytology* / Q000378:metabolism; D010063:Ovum / Q000166:cytology / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D051880:Receptors, Notch; D015398:Signal Transduction
D029721:Drosophila Proteins; D008565:Membrane Proteins; C497759:N protein, Drosophila; D011956:Receptors, Cell Surface; D051880:Receptors, Notch; D016695:Glycosyltransferases; D017351:N-Acetylglucosaminyltransferases; C090576:fng protein, Drosophila