title: The dREAM/Myb-MuvB complex and Grim are key regulators of the programmed death of neural precursor cells at the Drosophila posterior wing margin.
abstract: Successful development of a multicellular organism depends on the finely tuned orchestration of cell proliferation, differentiation and apoptosis from embryogenesis through adulthood. The MYB-gene family encodes sequence-specific DNA-binding transcription factors that have been implicated in the regulation of both normal and neoplastic growth. The Drosophila Myb protein, DMyb (and vertebrate B-Myb protein), has been shown to be part of the dREAM/MMB complex, a large multi-subunit complex, which in addition to four Myb-interacting proteins including Mip130, contains repressive E2F and pRB proteins. This complex has been implicated in the regulation of DNA replication within the context of chorion gene amplification and transcriptional regulation of a wide array of genes. Detailed phenotypic analysis of mutations in the Drosophila myb gene, Dm myb, has revealed a previously undiscovered function for the dREAM/MMB complex in regulating programmed cell death (PCD). In cooperation with the pro-apoptotic protein Grim and dREAM/MMB, DMyb promotes the PCD of specified sensory organ precursor daughter cells in at least two different settings in the peripheral nervous system: the pIIIb precursor of the neuron and sheath cells in the posterior wing margin and the glial cell in the thoracic microchaete lineage. Unlike previously analyzed settings, in which the main role of DMyb has been to antagonize the activities of other dREAM/MMB complex members, it appears to be the critical effector in promoting PCD. The finding that Dm myb and grim are both involved in regulating PCD in two distinct settings suggests that these two genes may often work together to mediate PCD.
authors.affiliation: Department of Biochemistry and Molecular Genetics University of Illinois at Chicago, 900 South Ashland Avenue, Chicago, IL 60607-7170, USA.
authors.forename: Margritte K
authors.initials: MK
authors.lastname: Rovani
authors.forename: Carrie Baker
authors.initials: CB
authors.lastname: Brachmann
authors.forename: Gary
authors.initials: G
authors.lastname: Ramsay
authors.forename: Alisa L
authors.initials: AL
authors.lastname: Katzen
mesh_terms: D000818:Animals; D017209:Apoptosis; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D020169:Caspases / Q000235:genetics* / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D016923:Cell Death; D002454:Cell Differentiation; D019070:Cell Lineage; D049109:Cell Proliferation; D004261:DNA Replication; D004330:Drosophila / Q000196:embryology / Q000235:genetics* / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D050684:E2F Transcription Factors / Q000235:genetics / Q000378:metabolism; D020570:Genes, myb; D009474:Neurons / Q000378:metabolism*; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism; D020598:Proto-Oncogene Proteins c-myb / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors; D014921:Wings, Animal / Q000196:embryology / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; D050684:E2F Transcription Factors; C496298:E2f1 protein, Drosophila; C489655:Mip130 protein, Drosophila; C467519:Myb protein, Drosophila; D009479:Neuropeptides; D020598:Proto-Oncogene Proteins c-myb; D014157:Transcription Factors; C108881:grim protein, Drosophila; D020169:Caspases; C438246:STRICA protein, Drosophila