title: Myc-dependent regulation of ribosomal RNA synthesis during Drosophila development.
abstract: Regulating ribosome number is thought to control cellular growth. Synthesis of ribosomal RNA (rRNA) is a limiting step in ribosome biogenesis and rates of rRNA synthesis are generally altered depending on the growth status of a cell. Although studies in unicellular systems have addressed the mechanisms by which this occurs, few studies have applied a genetic approach to examine growth-dependent control of rRNA synthesis in metazoans. Here, we show that in Drosophila melanogaster Myc (dMyc) is a regulator of rRNA synthesis. Expression of dMyc is both necessary and sufficient to control rRNA synthesis and ribosome biogenesis during larval development. Stimulation of rRNA synthesis by dMyc is mediated through a rapid, coordinated increase in the levels of the Pol I transcriptional machinery. In addition, the growth effects of dMyc in larval wing imaginal discs require de novo rRNA synthesis. We suggest that during animal development, the control of rRNA synthesis and ribosome biogenesis is an essential Myc function.
authors.affiliation: Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA.
authors.forename: Savraj S
authors.initials: SS
authors.lastname: Grewal
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.forename: Amir
authors.initials: A
authors.lastname: Orian
authors.forename: Robert N
authors.initials: RN
authors.lastname: Eisenman
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Edgar
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D002466:Cell Nucleolus / Q000378:metabolism; D004331:Drosophila melanogaster; D005434:Flow Cytometry; D018507:Gene Expression Regulation, Developmental; D049452:Green Fluorescent Proteins / Q000378:metabolism; D017403:In Situ Hybridization; D008856:Microscopy, Fluorescence; D008938:Mitosis; D020411:Oligonucleotide Array Sequence Analysis; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism*; D012313:RNA / Q000737:chemistry; D012335:RNA, Ribosomal / Q000737:chemistry* / Q000378:metabolism; D013997:Time Factors
chemical_list: D016271:Proto-Oncogene Proteins c-myc; D012335:RNA, Ribosomal; D049452:Green Fluorescent Proteins; D012313:RNA