Person: Perrimon, Norbert
Loading...
Email Address
AA Acceptance Date
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
Perrimon
First Name
Norbert
Name
Perrimon, Norbert
186 results
Search Results
Now showing 1 - 10 of 186
Publication Raf Acts Downstream of the EGF Receptor to Determine Dorsoventral Polarity During Drosophila Oogenesis(Cold Spring Harbor Laboratory, 1994-03-01) Brand, Andrea H.; Perrimon, NorbertPublication The Orthodenticle Gene Encodes a Novel Homeo Domain Protein Involved in the Development of the Drosophila Nervous System and Ocellar Visual Structures.(Cold Spring Harbor Laboratory, 1990-09) Finkelstein, Robert; Smouse, David; Capaci, Theresa M.; Spradling, Allan C.; Perrimon, NorbertThe orthodenticle (otd) locus of Drosophila is required for embryonic development, and null mutations of otd cause defects in head development and segmental patterning. We show here that otd is necessary for the formation of the embryonic central nervous system (CNS). otd mutations result in the formation of an abnormal neuropil and in the disappearance of identified neurons associated with the midline of the CNS. In addition, otd is allelic to ocelliless (oc), a mutation that causes the deletion of the ocelli of the adult fly. We have identified a transcription unit corresponding to the otd locus and find that it is expressed early in a stripe near the anterior pole of the cellular blastoderm and later in the region of the CNS from which these neurons normally arise. The predicted otd protein contains a well-conserved homeo domain and is therefore likely to be a transcriptional regulator involved in specifying cell fate both in the embryonic CNS and in the ocelli.Publication Mechanisms of Skeletal Muscle Aging: Insights From Drosophila and Mammalian Models(The Company of Biologists, 2013-11-01) Demontis, Fabio; Piccirillo, Rosanna; Goldberg, Alfred; Perrimon, NorbertA characteristic feature of aged humans and other mammals is the debilitating, progressive loss of skeletal muscle function and mass that is known as sarcopenia. Age-related muscle dysfunction occurs to an even greater extent during the relatively short lifespan of the fruit fly Drosophila melanogaster. Studies in model organisms indicate that sarcopenia is driven by a combination of muscle tissue extrinsic and intrinsic factors, and that it fundamentally differs from the rapid atrophy of muscles observed following disuse and fasting. Extrinsic changes in innervation, stem cell function and endocrine regulation of muscle homeostasis contribute to muscle aging. In addition, organelle dysfunction and compromised protein homeostasis are among the primary intrinsic causes. Some of these age-related changes can in turn contribute to the induction of compensatory stress responses that have a protective role during muscle aging. In this Review, we outline how studies in Drosophila and mammalian model organisms can each provide distinct advantages to facilitate the understanding of this complex multifactorial condition and how they can be used to identify suitable therapies.Publication Loss-of-Function Genetic Tools for Animal Models: Cross-Species and Cross-Platform Differences(Springer Science and Business Media LLC, 2017-01) Housden, Benjamin; Muhar, Matthias; Gemberling, Matthew; Gersbach, Charles A.; Stainier, Didier Y.R.; Seydoux, Geraldine; Mohr, Stephanie; Zuber, Johannes; Perrimon, NorbertOur understanding of the genetic mechanisms that underlie biological processes has relied extensively on loss-of-function (LOF) analyses. LOF methods target DNA, RNA or protein to reduce or to ablate gene function. By analysing the phenotypes that are caused by these perturbations the wild-type function of genes can be elucidated. Although all LOF methods reduce gene activity the choice of approach (for example, mutagenesis, CRISPR-based gene editing, RNA interference, morpholinos or pharmacological inhibition) can have a major effect on phenotypic outcomes. Interpretation of the LOF phenotype must take into account the biological process that is targeted by each method. The practicality and efficiency of LOF methods also vary considerably between model systems. We describe parameters for choosing the optimal combination of method and system, and for interpreting phenotypes within the constraints of each method.Publication The Circadian Clock Gates the Intestinal Stem Cell Regenerative State(Elsevier BV, 2013-04-25) Karpowicz, Phillip; Zhang, Yong; Hogenesch, John B.; Emery, Patrick; Perrimon, NorbertThe intestine has evolved under constant environmental stresses, because an animal may ingest harmful pathogens or chemicals at any time during its lifespan. Following damage, intestinal stem cells (ISCs) regenerate the intestine by proliferating to replace dying cells. ISCs from diverse animals are remarkably similar, and the Wnt, Notch, and Hippo signaling pathways, important regulators of mammalian ISCs, are conserved from flies to humans. Unexpectedly, we identified the transcription factor period, a component of the circadian clock, to be critical for regeneration, which itself follows a circadian rhythm. We discovered hundreds of transcripts that are regulated by the clock during intestinal regeneration, including components of stress response and regeneration pathways. Disruption of clock components leads to arrhythmic ISC divisions, revealing their underappreciated role in the healing process.Publication Ecdysone Signaling at Metamorphosis Triggers Apoptosis of Drosophila Abdominal Muscles(Elsevier BV, 2013-11-15) Zirin, Jonathan; Cheng, Daojun; Dhanyasi, Nagaraju; Cho, Julio; Dura, Jean-Maurice; VijayRaghavan, Krishnaswamy; Perrimon, NorbertOne of the most dramatic examples of programmed cell death occurs during Drosophila metamorphosis, when most of the larval tissues are destroyed in a process termed histolysis. Much of our understanding of this process comes from analyses of salivary gland and midgut cell death. In contrast, relatively little is known about the degradation of the larval musculature. Here, we analyze the programmed destruction of the abdominal dorsal exterior oblique muscle (DEOM) which occurs during the first 24 hrs of metamorphosis. We find that ecdysone signaling through Ecdysone receptor isoform B1 is required cell autonomously for the muscle death. Furthermore, we show that the orphan nuclear receptor FTZ-F1, opposed by another nuclear receptor, HR39, plays a critical role in the timing of DEOM histolysis. Finally, we show that unlike the histolysis of salivary gland and midgut, abdominal muscle death occurs by apoptosis, and does not require autophagy. Thus, there is no set rule as to the role of autophagy and apoptosis during Drosophila histolysis.Publication A Temperature-Sensitive MEK Mutation Demonstrates the Conservation of the Signaling Pathways Activated by Receptor Tyrosine Kinases(Cold Spring Harbor Laboratory, 1994-09-15) Hsu, Jui-Chou; Perrimon, NorbertMEK, a dual specificity threonine/tyrosine kinase, has been postulated to be a convergent point for signaling from receptor protein tyrosine kinases (RTKs) and G-protein-coupled receptors. In contrast to yeast and mammalian cells where several MEKs have been isolated, only one Drosophila MEK (D-Mek) has been characterized to date. Previous studies have shown that D-Mek acts in the Torso RTK signaling pathway. To demonstrate that D-Mek also operates downstream of other RTKs, we generated a temperature-sensitive allele of D-mek (D-mekts) by site-directed mutagenesis based on the amino acid change of a yeast cdc2ts mutation. Using D-mekts, we show that in addition to its role in Torso signaling, D-Mek operates in the Sevenless and in the Drosophila epidermal growth factor RTK pathways. Because loss-of-function mutations in D-mek and the upstream receptors give rise to similar phenotypes, it suggests that D-mek is the only MEK activated by Drosophila RTKs. In addition, we demonstrate that different RTK pathways respond differently to alteration in D-Mek activity.Publication FOXO/4E-BP Signaling in Drosophila Muscles Regulates Organism-Wide Proteostasis During Aging(Elsevier BV, 2010-11-24) Demontis, Fabio; Perrimon, NorbertThe progressive loss of muscle strength during aging is a common degenerative event of unclear pathogenesis. Although muscle functional decline precedes age-related changes in other tissues, its contribution to systemic aging is unknown. Here, we show that muscle aging is characterized in Drosophila by the progressive accumulation of protein aggregates that associate with impaired muscle function. The transcription factor FOXO and its target 4E-BP remove damaged proteins at least in part via the autophagy/lysosome system, while foxo mutants have dysfunctional proteostasis. Both FOXO and 4E-BP delay muscle functional decay and extend lifespan. Moreover, FOXO/4E-BP signaling in muscles decreases feeding behavior and the release of Insulin from producing cells, which in turn delays the age-related accumulation of protein aggregates in other tissues. These findings reveal an organism-wide regulation of proteostasis in response to muscle aging, and a key role of FOXO/4E-BP signaling in the coordination of organismal and tissue aging.Publication The Porcupine Gene Is Required for Wingless Autoregulation in Drosophila(The Company of Biologists, 1995-12-01) Manoukian, Armen S.; Yoffe, Kenneth B.; Wilder, Elizabeth L.; Perrimon, NorbertThe Drosophila segment polarity gene wingless (wg) is required in the regulation of engrailed (en) expression and the determination of cell fates in neighboring cells. This paracrine wg activity also regulates transcription of wg itself, through a positive feedback loop including en activity. In addition, wg has a second, more direct autoregulatory requirement that is distinct from the en-dependent feedback loop. Four gene products, encoded by armadillo (arm), dishevelled (dsh), porcupine (porc) and zeste-white 3 (zw3), have been previously implicated as components of wg paracrine signaling. Here we have used three different assays to assess the requirements of these genes in the more direct wg autoregulatory pathway. While the activities of dsh, zw3 and arm appear to be specific to the paracrine feedback pathway, the more direct autoregulatory pathway requires porc.Publication Unusually effective microRNA targeting within repeat-rich coding regions of mammalian mRNAs(Cold Spring Harbor Laboratory, 2011-06-17) Schnall-Levin, Michael; Rissland, Olivia S.; Johnston, Wendy K.; Perrimon, Norbert; Bartel, David P.; Berger, BonnieMicroRNAs (miRNAs) regulate numerous biological processes by base-pairing with target messenger RNAs (mRNAs), primarily through sites in 3′ untranslated regions (UTRs), to direct the repression of these targets. Although miRNAs have sometimes been observed to target genes through sites in open reading frames (ORFs), large-scale studies have shown such targeting to be generally less effective than 3′ UTR targeting. Here, we show that several miRNAs each target significant groups of genes through multiple sites within their coding regions. This ORF targeting, which mediates both predictable and effective repression, arises from highly repeated sequences containing miRNA target sites. We show that such sequence repeats largely arise through evolutionary duplications and occur particularly frequently within families of paralogous C2H2 zinc-finger genes, suggesting the potential for their coordinated regulation. Examples of ORFs targeted by miR-181 include both the well-known tumor suppressor RB1 and RBAK, encoding a C2H2 zinc-finger protein and transcriptional binding partner of RB1. Our results indicate a function for repeat-rich coding sequences in mediating post-transcriptional regulation and reveal circumstances in which miRNA-mediated repression through ORF sites can be reliably predicted.