title: Maternal and zygotic requirement for thepolyhomeotic complex genetic locus inDrosophila.
abstract: The complex genetic locuspolyhomeotic (ph) is a member of thePolycomb (Pc)-group of genes and as such is required for the normal expression of ANT-C and BX-C genes. It also has probably other functions since amorphicph alleles display a cell death phenotype in the ventral epidermis of 12-h-old embryos. Here it is shown that lethal alleles ofph (amorph and strong hypomorph) show transformation of most of their segments towards AB8. Theph+product is required autonomously in imaginal cells. The total lack ofph+function prevents viability of the cuticular derivatives of these cells.ph has a strong maternal effect on segmental identity and epidermal development that can not be rescued by one paternally supplied dose ofph+in the zygote. These phenotypes differ substantially from those of previously describedPc-group genes. AmongPc-group genes,ph seems to be the only one that is strongly required both maternally and zygotically for normal embryonic development.
authors.affiliation: Centre de Génétique Moléculaire, C.N.R.S., F-91190, Gif-sur-Yvette, France.|Laboratoire propre du C.N.R.S., associé à l'Université Pierre et Marie Curie, Paris VI, France.
authors.forename: Jean-Maurice
authors.initials: JM
authors.lastname: Dura
authors.affiliation: Centre de Génétique Moléculaire, C.N.R.S., F-91190, Gif-sur-Yvette, France.|Laboratoire propre du C.N.R.S., associé à l'Université Pierre et Marie Curie, Paris VI, France.
authors.forename: Janet
authors.initials: J
authors.lastname: Deatrick
authors.affiliation: Centre de Génétique Moléculaire, C.N.R.S., F-91190, Gif-sur-Yvette, France.|Laboratoire propre du C.N.R.S., associé à l'Université Pierre et Marie Curie, Paris VI, France.
authors.forename: Neel B
authors.initials: NB
authors.lastname: Randsholt
authors.affiliation: Centre de Génétique Moléculaire, C.N.R.S., F-91190, Gif-sur-Yvette, France.|Laboratoire propre du C.N.R.S., associé à l'Université Pierre et Marie Curie, Paris VI, France.
authors.forename: Hugh W
authors.initials: HW
authors.lastname: Brock
authors.affiliation: Centre de Génétique Moléculaire, C.N.R.S., F-91190, Gif-sur-Yvette, France.|Laboratoire propre du C.N.R.S., associé à l'Université Pierre et Marie Curie, Paris VI, France.
authors.forename: Pedro
authors.initials: P
authors.lastname: Santamaria
keywords: Clonal analysis; Drosophila; Embryology; Epidermal development; Homeosis