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Vollmer J, Fried P, Aguilar-Hidalgo D, Sánchez-Aragón M, Iannini A, Casares F, Iber D. Growth control in the Drosophila eye disc by the cytokine Unpaired. Development 2017; 144:837-843. [PMID: 28246213 DOI: 10.1242/dev.141309] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 01/10/2017] [Indexed: 01/14/2023]
Abstract
A fundamental question in developmental biology is how organ size is controlled. We have previously shown that the area growth rate in the Drosophila eye primordium declines inversely proportionally to the increase in its area. How the observed reduction in the growth rate is achieved is unknown. Here, we explore the dilution of the cytokine Unpaired (Upd) as a possible candidate mechanism. In the developing eye, upd expression is transient, ceasing at the time when the morphogenetic furrow first emerges. We confirm experimentally that the diffusion and stability of the JAK/STAT ligand Upd are sufficient to control eye disc growth via a dilution mechanism. We further show that sequestration of Upd by ectopic expression of an inactive form of the receptor Domeless (Dome) results in a substantially lower growth rate, but the area growth rate still declines inversely proportionally to the area increase. This growth rate-to-area relationship is no longer observed when Upd dilution is prevented by the continuous, ectopic expression of Upd. We conclude that a mechanism based on the dilution of the growth modulator Upd can explain how growth termination is controlled in the eye disc.
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Affiliation(s)
- Jannik Vollmer
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, Basel 4058, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, Basel 4058, Switzerland
| | - Patrick Fried
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, Basel 4058, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, Basel 4058, Switzerland
| | - Daniel Aguilar-Hidalgo
- Department of Gene Regulation and Morphogenesis, CABD, Universidad Pablo de Olavide, Seville 41013, Spain
| | - Máximo Sánchez-Aragón
- Department of Gene Regulation and Morphogenesis, CABD, Universidad Pablo de Olavide, Seville 41013, Spain
| | - Antonella Iannini
- Department of Gene Regulation and Morphogenesis, CABD, Universidad Pablo de Olavide, Seville 41013, Spain
| | - Fernando Casares
- Department of Gene Regulation and Morphogenesis, CABD, Universidad Pablo de Olavide, Seville 41013, Spain
| | - Dagmar Iber
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, Basel 4058, Switzerland .,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, Basel 4058, Switzerland
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2
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Zoranovic T, Grmai L, Bach EA. Regulation of proliferation, cell competition, and cellular growth by the Drosophila JAK-STAT pathway. JAKSTAT 2013; 2:e25408. [PMID: 24069565 PMCID: PMC3772117 DOI: 10.4161/jkst.25408] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 06/06/2013] [Accepted: 06/14/2013] [Indexed: 01/08/2023] Open
Abstract
The JAK-STAT pathway is a key regulator of tissue size in Drosophila melanogaster. Here we provide an overview of its roles in processes that regulate the size of Drosophila imaginal discs, epithelia of diploid cells that proliferate and acquire specific fates in the larvae and that become functional in the adult. Drosophila has a single JAK and a single STAT gene, which has facilitated genetic dissection of this pathway. Moreover, the sophisticated genetic tools available in flies for clonal growth assays have made Drosophila an ideal organism in which to dissect the multiple roles of the JAK-STAT pathway in growth control. Studies in flies have revealed JAK-STAT pathway activity as a central node for diverse signals that control proliferation and mass accumulation. In addition, recent work has establish a new role for the pathway in cell competition, a process thought to be akin to the early stages of transformation in which more robust cells kill and take the place of less robust ones.
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Affiliation(s)
- Tamara Zoranovic
- Department of Biochemistry and Molecular Pharmacology; New York University School of Medicine; New York, NY USA
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3
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Characterization of a dominant-active STAT that promotes tumorigenesis in Drosophila. Dev Biol 2010; 344:621-36. [PMID: 20501334 DOI: 10.1016/j.ydbio.2010.05.497] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Accepted: 05/15/2010] [Indexed: 01/08/2023]
Abstract
Little is known about the molecular mechanisms by which STAT proteins promote tumorigenesis. Drosophila is an ideal system for investigating this issue, as there is a single STAT (Stat92E), and its hyperactivation causes overgrowths resembling human tumors. Here we report the first identification of a dominant-active Stat92E protein, Stat92E(DeltaNDeltaC), which lacks both N- and C-termini. Mis-expression of Stat92E(DeltaNDeltaC)in vivo causes melanotic tumors, while in vitro it transactivates a Stat92E-luciferase reporter in the absence of stimulation. These gain-of-function phenotypes require phosphorylation of Y(711) and dimer formation with full-length Stat92E. Furthermore, a single point mutation, an R(442P) substitution in the DNA-binding domain, abolishes Stat92E function. Recombinant Stat92E(R442P) translocates to the nucleus following activation but fails to function in all assays tested. Interestingly, R(442) is conserved in most STATs in higher organisms, suggesting conservation of function. Modeling of Stat92E indicates that R(442) may contact the minor groove of DNA via invariant TC bases in the consensus binding element bound by all STAT proteins. We conclude that the N- and C- termini function unexpectedly in negatively regulating Stat92E activity, possibly by decreasing dimer dephosphorylation or increasing stability of DNA interaction, and that Stat92E(R442) has a nuclear function by altering dimer:DNA binding.
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Schaeffer SW, Bhutkar A, McAllister BF, Matsuda M, Matzkin LM, O'Grady PM, Rohde C, Valente VLS, Aguadé M, Anderson WW, Edwards K, Garcia ACL, Goodman J, Hartigan J, Kataoka E, Lapoint RT, Lozovsky ER, Machado CA, Noor MAF, Papaceit M, Reed LK, Richards S, Rieger TT, Russo SM, Sato H, Segarra C, Smith DR, Smith TF, Strelets V, Tobari YN, Tomimura Y, Wasserman M, Watts T, Wilson R, Yoshida K, Markow TA, Gelbart WM, Kaufman TC. Polytene chromosomal maps of 11 Drosophila species: the order of genomic scaffolds inferred from genetic and physical maps. Genetics 2008; 179:1601-55. [PMID: 18622037 PMCID: PMC2475758 DOI: 10.1534/genetics.107.086074] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2007] [Accepted: 03/13/2008] [Indexed: 11/18/2022] Open
Abstract
The sequencing of the 12 genomes of members of the genus Drosophila was taken as an opportunity to reevaluate the genetic and physical maps for 11 of the species, in part to aid in the mapping of assembled scaffolds. Here, we present an overview of the importance of cytogenetic maps to Drosophila biology and to the concepts of chromosomal evolution. Physical and genetic markers were used to anchor the genome assembly scaffolds to the polytene chromosomal maps for each species. In addition, a computational approach was used to anchor smaller scaffolds on the basis of the analysis of syntenic blocks. We present the chromosomal map data from each of the 11 sequenced non-Drosophila melanogaster species as a series of sections. Each section reviews the history of the polytene chromosome maps for each species, presents the new polytene chromosome maps, and anchors the genomic scaffolds to the cytological maps using genetic and physical markers. The mapping data agree with Muller's idea that the majority of Drosophila genes are syntenic. Despite the conservation of genes within homologous chromosome arms across species, the karyotypes of these species have changed through the fusion of chromosomal arms followed by subsequent rearrangement events.
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Affiliation(s)
- Stephen W Schaeffer
- Department of Biology and Institute of Molecular Evolutionary Genetics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
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5
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Hombría JCG, Brown S, Häder S, Zeidler MP. Characterisation of Upd2, a Drosophila JAK/STAT pathway ligand. Dev Biol 2005; 288:420-33. [PMID: 16277982 DOI: 10.1016/j.ydbio.2005.09.040] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2005] [Revised: 09/26/2005] [Accepted: 09/29/2005] [Indexed: 11/24/2022]
Abstract
The characterisation of ligands that activate the JAK/STAT pathway has the potential to throw light onto a comparatively poorly understood aspect of this important signal transduction cascade. Here, we describe our analysis of the only invertebrate JAK/STAT pathway ligands identified to date, the Drosophila unpaired-like family. We show that upd2 is expressed in a pattern essentially identical to that of upd and demonstrate that the proteins encoded by this region activate JAK/STAT pathway signalling. Mutational analysis demonstrates a mutual semi-redundancy that can be visualised in multiple tissues known to require JAK/STAT signalling. In order to better characterise the in vivo function of these ligands, we developed a reporter based on a natural JAK/STAT pathway responsive enhancer and show that ectopic upd2 expression can effectively activate the JAK/STAT pathway. While both Upd and Upd2 are secreted JAK/STAT pathway agonists, tissue culture assays show that the signal-sequences of Upd and Upd2 confer distinct properties, with Upd associated primarily with the extracellular matrix and Upd2 secreted into the media. The differing biophysical characteristics identified for Upd-like molecules have implications for their function in vivo and adds another aspect to our understanding of cytokine signalling in Drosophila.
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Affiliation(s)
- James Castelli-Gair Hombría
- Centro Andaluz de Biología del Desarrollo, CSIC/Universidad Pablo de Olavide, Carretera de Utrera, Km 1, 41013 Seville, Spain.
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Tsai YC, Sun YH. Long-range effect of upd, a ligand for Jak/STAT pathway, on cell cycle in Drosophila eye development. Genesis 2005; 39:141-53. [PMID: 15170700 DOI: 10.1002/gene.20035] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
unpaired (upd) encodes a ligand for the Jak/STAT signaling pathway in Drosophila. In the second instar and early third larval eye disc, upd is expressed in the center of the posterior margin. upd loss-of-function mutations caused eye size reduction and upd overexpression caused eye enlargement. Upd regulates eye size through the Dome/Jak(Hop)/STAT92 signaling pathway to promote cell proliferation. Interestingly, the effect of Upd is only on cells located anterior to the morphogenetic furrow (MF), but has no effect on the second mitotic wave, which is posterior to MF. Overexpression of upd behind MF can nonautonomously induce cell proliferation up to 20 rows of cells anterior to MF. The G1 cyclin, cycD transcript level was also enhanced anterior to MF. Consistent with the long-range effect, we found that the extracellular Upd protein can be detected over a comparable long range, suggesting that Upd acts directly over a long distance as a signaling molecule.
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Affiliation(s)
- Yu-Chen Tsai
- Institute of Genetics, National Yang-Ming University, Taipei, Taiwan, Republic of China
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7
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Bach EA, Vincent S, Zeidler MP, Perrimon N. A Sensitized Genetic Screen to Identify Novel Regulators and Components of the Drosophila Janus Kinase/Signal Transducer and Activator of Transcription Pathway. Genetics 2003; 165:1149-66. [PMID: 14668372 PMCID: PMC1462825 DOI: 10.1093/genetics/165.3.1149] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
The JAK/STAT pathway exerts pleiotropic effects on a wide range of developmental processes in Drosophila. Four key components have been identified: Unpaired, a secreted ligand; Domeless, a cytokine-like receptor; Hopscotch, a JAK kinase; and Stat92E, a STAT transcription factor. The identification of additional components and regulators of this pathway remains an important issue. To this end, we have generated a transgenic line where we misexpress the upd ligand in the developing Drosophila eye. GMR-upd transgenic animals have dramatically enlarged eye-imaginal discs and compound eyes that are normally patterned. We demonstrate that the enlarged-eye phenotype is a result of an increase in cell number, and not cell volume, and arises from additional mitoses in larval eye discs. Thus, the GMR-upd line represents a system in which the proliferation and differentiation of eye precursor cells are separable. Removal of one copy of stat92E substantially reduces the enlarged-eye phenotype. We performed an F1 deficiency screen to identify dominant modifiers of the GMR-upd phenotype. We have identified 9 regions that enhance this eye phenotype and two specific enhancers: C-terminal binding protein and Daughters against dpp. We also identified 20 regions that suppress GMR-upd and 13 specific suppressors: zeste-white 13, pineapple eye, Dichaete, histone 2A variant, headcase, plexus, kohtalo, crumbs, hedgehog, decapentaplegic, thickveins, saxophone, and Mothers against dpp.
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Affiliation(s)
- Erika A Bach
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.
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8
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Kuniyoshi H, Baba K, Ueda R, Kondo S, Awano W, Juni N, Yamamoto D. lingerer, a Drosophila gene involved in initiation and termination of copulation, encodes a set of novel cytoplasmic proteins. Genetics 2002; 162:1775-89. [PMID: 12524348 PMCID: PMC1462391 DOI: 10.1093/genetics/162.4.1775] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In an effort to uncover genetic components underlying the courtship behavior of Drosophila melanogaster, we have characterized a novel gene, lingerer (lig), mutations of which result in abnormal copulation. Males carrying a hypomorphic mutation in lig fail to withdraw their genitalia upon termination of copulation, but display no overt abnormalities in their genitalia. A severe reduction in the dosage of the lig gene causes repeated attempted copulations but no successful copulations. Complete loss of lig function results in lethality during early pupal stages. lig is localized to polytene segment 44A on the second chromosome and encodes three alternatively spliced transcripts that generate two types of 150-kD proteins, Lig-A and Lig-B, differing only at the C terminus. Lig proteins show no similarity to known proteins. However, a set of homologous proteins in mammals suggest that Drosophila Lig belongs to a family of proteins that share five highly conserved domains. Lig is a cytoplasmic protein expressed in the central nervous system (CNS), imaginal discs, and gonads. Lig-A expression is selectively reduced in lig mutants and the ubiquitous supply of this protein at the beginning of metamorphosis restores the copulatory defects of the lig mutant. We propose that lig may act in the nervous system to mediate the control of copulatory organs during courtship.
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Affiliation(s)
- Hisato Kuniyoshi
- ERATO Yamamoto Behavior Genes Project, Japan Science and Technology Corporation at Mitsubishi Kasei Institute of Life Sciences, Tokyo 194-8511, Japan
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9
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Lukacsovich T, Asztalos Z, Awano W, Baba K, Kondo S, Niwa S, Yamamoto D. Dual-tagging gene trap of novel genes in Drosophila melanogaster. Genetics 2001; 157:727-42. [PMID: 11156992 PMCID: PMC1461519 DOI: 10.1093/genetics/157.2.727] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A gene-trap system is established for Drosophila. Unlike the conventional enhancer-trap system, the gene-trap system allows the recovery only of fly lines whose genes are inactivated by a P-element insertion, i.e., mutants. In the gene-trap system, the reporter gene expression reflects precisely the spatial and temporal expression pattern of the trapped gene. Flies in which gene trap occurred are identified by a two-step screening process using two independent markers, mini-w and Gal4, each indicating the integration of the vector downstream of the promoter of a gene (dual tagging). mini-w has its own promoter but lacks a polyadenylation signal. Therefore, mini-w mRNA is transcribed from its own promoter regardless of the vector integration site in the genome. However, the eyes of flies are not orange or red unless the vector is incorporated into a gene enabling mini-w to be spliced to a downstream exon of the host gene and polyadenylated at the 3' end. The promoter-less Gal4 reporter is expressed as a fusion mRNA only when it is integrated downstream of the promoter of a host gene. The exons of trapped genes can be readily cloned by vectorette RT-PCR, followed by RACE and PCR using cDNA libraries. Thus, the dual-tagging gene-trap system provides a means for (i) efficient mutagenesis, (ii) unequivocal identification of genes responsible for mutant phenotypes, (iii) precise detection of expression patterns of trapped genes, and (iv) rapid cloning of trapped genes.
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MESH Headings
- Animals
- Base Sequence
- Chromosomes/metabolism
- Crosses, Genetic
- DNA, Complementary/metabolism
- Drosophila melanogaster/genetics
- Enhancer Elements, Genetic
- Exons
- Female
- Gene Library
- Genes, Reporter
- Genetic Techniques
- Genetic Vectors
- In Situ Hybridization
- Male
- Microscopy, Electron, Scanning
- Models, Genetic
- Molecular Sequence Data
- Mutagenesis
- Phenotype
- Photoreceptor Cells, Invertebrate/embryology
- Photoreceptor Cells, Invertebrate/pathology
- Promoter Regions, Genetic
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- T Lukacsovich
- School of Human Sciences and Advanced Research Institute for Science and Engineering, Waseda University, Saitama 359-1192, Japan
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10
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Goto SG. Expression of Drosophila homologue of senescence marker protein-30 during cold acclimation. JOURNAL OF INSECT PHYSIOLOGY 2000; 46:1111-1120. [PMID: 10817837 DOI: 10.1016/s0022-1910(99)00221-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Gene expression during cold acclimation at a moderately low temperature (15 degrees C) was studied in Drosophila melanogaster using a subtraction technique. A gene homologous to senescence marker protein-30 (SMP30), which has a Ca(2+)-binding function, was up-regulated at the transcription level after acclimation to 15 degrees C. This gene (henceforth referred to as Dca) was also expressed at a higher level in individuals reared at 15 degrees C from the egg stage than in those reared at 25 degrees C. Moreover, DCA mRNA increased at the senescent stage in Drosophila, although SMP30 is reported to decrease at senescent stages in mammals. In situ hybridization to polytene chromosomes revealed that the Dca gene was located at 88D on chromosome 3R. The 5' flanking region of this gene had AP-1 (a transcription factor of SMP30) binding sites, stress response element and some other transcription factor binding sites. The function of DCA was discussed in relation to the possible regulation of cytosolic Ca(2+) concentration.
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Affiliation(s)
- SG Goto
- Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Japan
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11
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Abstract
The JAK/STAT signal transduction pathway has been conserved throughout evolution such that true structural and functional homologues of components originally identified in vertebrate systems are also present in the model genetic system Drosophila melanogaster. In addition to roles during larval hematopoiesis reminiscent of the requirement for this pathway in mammalian systems, the JAK/STAT pathway in Drosophila is also involved in a number of other developmental events. Recent data has demonstrated further roles for the JAK/STAT pathway in the establishment of sexual identity via the early embryonic expression of Sex lethal, the segmentation of the embryo via the control of pair rule genes including even skipped and the establishment of polarity within the adult compound eye via a mechanism that includes the four jointed gene. Use of the powerful genetics in the model organism Drosophila may identify new components of the JAK/STAT pathway, define new roles for this pathway, and provide insights into the function of this signal transduction system. Here we review the roles of STAT and its associated signaling pathway during both embryonic and adult stages of Drosophila development and discuss future prospects for the identification and characterization of novel pathway components and targets. Oncogene (2000).
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Affiliation(s)
- M P Zeidler
- Department of Genetics, Howard Hughes Medical Institute, Harvard Medical School, 200 Longwood Avenue, Boston, Massachusetts, MA 02115, USA
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12
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Lukacsovich T, Asztalos Z, Juni N, Awano W, Yamamoto D. The Drosophila melanogaster 60A chromosomal division is extremely dense with functional genes: their sequences, genomic organization, and expression. Genomics 1999; 57:43-56. [PMID: 10191082 DOI: 10.1006/geno.1999.5746] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We cloned and sequenced genomic DNA contigs spanning over 45 kb, surrounding the insertion site of the P-element that is responsible for the developmental defects in the ken and barbie (ken) mutant of Drosophila. This region harbors 10 functional transcription units, in addition to the already well-characterized TGFbeta-60A gene. These include the genes, undefined 1 (UD1), UD2, and UD3, each coding for proteins of unknown function, the ken gene encoding a new Krüppel-like putative transcription factor, the fly homologues of the mammalian mitochondrial trifunctional enzyme (thiolase), and the TAR DNA-binding protein-43 (TBPH), the first nonvertebrate member of the transmembrane 4 superfamily (TM4SF) gene, a new homeodomain gene, and a gene coding for a putative nuclear binding protein (PNBP) that is homologous to maleless, and a Copia-like element. UD3 exists in an intron of the maleless homologue, yet is expressed independent of it. The UD1 and TM4SF genes orient in a tail-to-tail manner with their 3' untranslated region sequences overlapping over 44 nucleotides. Thus the partial overlap and intraintronic organization permitted dense packing of the functional genes within a short segment of the genome.
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Affiliation(s)
- T Lukacsovich
- ERATO Yamamoto Behavior Genes Project, Mitsubishi Kasei Institute of Life Sciences, Machida, 194-8511, Japan
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13
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Harrison DA, McCoon PE, Binari R, Gilman M, Perrimon N. Drosophila unpaired encodes a secreted protein that activates the JAK signaling pathway. Genes Dev 1998; 12:3252-63. [PMID: 9784499 PMCID: PMC317220 DOI: 10.1101/gad.12.20.3252] [Citation(s) in RCA: 279] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In vertebrates, many cytokines and growth factors have been identified as activators of the JAK/STAT signaling pathway. In Drosophila, JAK and STAT molecules have been isolated, but no ligands or receptors capable of activating the pathway have been described. We have characterized the unpaired (upd) gene, which displays the same distinctive embryonic mutant defects as mutations in the Drosophila JAK (hopscotch) and STAT (stat92E) genes. Upd is a secreted protein, associated with the extracellular matrix, that activates the JAK pathway. We propose that Upd is a ligand that relies on JAK signaling to stimulate transcription of pair-rule genes in a segmentally restricted manner in the early Drosophila embryo.
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Affiliation(s)
- D A Harrison
- Department of Genetics, Boston, Massachusetts 02115 USA.
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14
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Nijhout HF, Emlen DJ. Competition among body parts in the development and evolution of insect morphology. Proc Natl Acad Sci U S A 1998; 95:3685-9. [PMID: 9520426 PMCID: PMC19896 DOI: 10.1073/pnas.95.7.3685] [Citation(s) in RCA: 315] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Changes in form during ontogeny and evolution depend in large measure on changes in the relative growth of the various parts of the body. The current consensus in developmental biology is that the final size of appendages and internal organs is regulated autonomously, within the structure itself. Size regulation of body parts typically requires no external control and is thought to be relatively insensitive to signals from the developmental environment. We show in two very different systems, butterfly wings and beetle horns, that experimentally induced changes in the allocation of developmental resources to one trait produces compensatory changes in the relative sizes of other traits. These findings illustrate that interaction among body parts in development is part of the mechanism of size regulation of those parts. Furthermore, in the case of beetle horns, we show that the tradeoff in size is manifest as a significant negative genetic correlation among the involved body parts and, therefore, constitutes a developmental source of genetic constraint on the evolution of body form.
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Affiliation(s)
- H F Nijhout
- Department of Zoology Duke University Durham, NC 27708-0325, USA.
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