title: Conserved roles of ems/Emx and otd/Otx genes in olfactory and visual system development in Drosophila and mouse.
abstract: The regional specialization of brain function has been well documented in the mouse and fruitfly. The expression of regulatory factors in specific regions of the brain during development suggests that they function to establish or maintain this specialization. Here, we focus on two such factors-the Drosophila cephalic gap genes empty spiracles (ems) and orthodenticle (otd), and their vertebrate homologues Emx1/2 and Otx1/2-and review novel insight into their multiple crucial roles in the formation of complex sensory systems. While the early requirement of these genes in specification of the neuroectoderm has been discussed previously, here we consider more recent studies that elucidate the later functions of these genes in sensory system formation in vertebrates and invertebrates. These new studies show that the ems and Emx genes in both flies and mice are essential for the development of the peripheral and central neurons of their respective olfactory systems. Moreover, they demonstrate that the otd and Otx genes in both flies and mice are essential for the development of the peripheral and central neurons of their respective visual systems. Based on these recent experimental findings, we discuss the possibility that the olfactory and visual systems of flies and mice share a common evolutionary origin, in that the conserved visual and olfactory circuit elements derive from conserved domains of otd/Otx and ems/Emx action in the urbilaterian ancestor.
authors: National Centre for Biological Sciences, Tata Institute of Fundamental Research, UAS-GKVK Campus, Bellary Road, Bangalore 560065, India.
authors: Sonia
authors: S
authors: Sen
authors: Heinrich
authors: H
authors: Reichert
authors: K
authors: K
authors: VijayRaghavan
mesh_terms: D000818:Animals; D057506:Arthropod Antennae / Q000254:growth & development / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism; D019143:Evolution, Molecular; D005123:Eye / Q000254:growth & development / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D009832:Olfactory Nerve / Q000378:metabolism; D018034:Olfactory Receptor Neurons / Q000378:metabolism; D051857:Otx Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D017956:Photoreceptor Cells, Invertebrate / Q000378:metabolism*; D020419:Photoreceptor Cells, Vertebrate / Q000166:cytology / Q000378:metabolism; D055351:Retinal Neurons / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D000099260:Empty Spiracles Homeobox Proteins
chemical_list: D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D051857:Otx Transcription Factors; D014157:Transcription Factors; D000099260:Empty Spiracles Homeobox Proteins; C497656:Otx1 protein, mouse; C497660:Otx2 protein, mouse; C093054:ems protein, Drosophila; C093053:oc protein, Drosophila
keywords: Emx1/2, Otx1/2; empty spiracles; evolutionary conservation; orthodenticle; sensory systems
references: Neuron. 1999 Dec;24(4):819-31
references: 10624946
references: Development. 1996 Jan;122(1):243-52
references: 8565836
references: Development. 1998 May;125(9):1691-702
references: 9521907
references: Mech Dev. 1998 Oct;77(2):165-72
references: 9831645
references: Development. 1997 Jan;124(1):101-11
references: 9006071
references: Nature. 1992 Aug 20;358(6388):687-90
references: 1353865
references: Neuron. 2010 Apr 15;66(1):15-36
references: 20399726
references: Dev Biol. 2010 Nov 1;347(1):122-32
references: 20732315
references: Adv Exp Med Biol. 2008;628:69-81
references: 18683639
references: Dev Biol. 2008 Mar 15;315(2):521-34
references: 18241855
references: Curr Biol. 2000 Mar 23;10(6):301-10
references: 10744971
references: Adv Exp Med Biol. 2008;628:32-41
references: 18683636
references: Cell. 2007 Apr 20;129(2):277-88
references: 17448990
references: J Neurosci. 2002 Nov 1;22(21):9255-66
references: 12417651
references: Dev Biol. 1978 Aug;65(2):296-321
references: 98369
references: Development. 1995 Oct;121(10):3279-90
references: 7588062
references: EMBO J. 1993 Jul;12(7):2735-47
references: 8101484
references: J Neurosci. 1994 Oct;14(10):5725-40
references: 7931541
references: Nat Genet. 1999 Dec;23(4):466-70
references: 10581037
references: J Comp Neurol. 2003 Mar 17;457(4):345-60
references: 12561075
references: Development. 1999 Jun;126(11):2309-25
references: 10225991
references: Cell. 1997 Nov 14;91(4):531-41
references: 9390562
references: Trends Neurosci. 2000 Aug;23(8):347-52
references: 10906797
references: Neuron. 1995 Oct;15(4):769-78
references: 7576627
references: EMBO J. 1992 Jul;11(7):2541-50
references: 1352754
references: Cell. 2010 Sep 3;142(5):800-9
references: 20813265
references: EMBO J. 1992 Jun;11(6):2247-59
references: 1376248
references: Development. 2010 Sep 1;137(17):2895-904
references: 20667913
references: Genome Res. 2010 Nov;20(11):1512-25
references: 20693478
references: Development. 2001 Jun;128(11):2019-30
references: 11493524
references: Neural Dev. 2008 Dec 03;3:33
references: 19055770
references: Cell. 2011 Jun 10;145(6):956-68
references: 21663797
references: Genes Dev. 1995 Nov 1;9(21):2646-58
references: 7590242
references: Genes Dev. 1989 Dec;3(12A):1940-56
references: 2576012
references: Semin Cell Dev Biol. 2006 Aug;17(4):433-42
references: 16766212
references: Wilehm Roux Arch Dev Biol. 1984 Sep;193(5):308-325
references: 28305340
references: Annu Rev Neurosci. 1997;20:595-631
references: 9056726
references: Proc Natl Acad Sci U S A. 1994 Aug 30;91(18):8363-7
references: 7915837
references: Neuron. 1997 Nov;19(5):1017-30
references: 9390516
references: Genes Dev. 1990 Sep;4(9):1516-27
references: 1979296
references: BMC Neurosci. 2005 Jan 27;6:5
references: 15676071
references: Cell. 1987 Sep 25;50(7):1139-53
references: 3113740
references: Nature. 1990 Aug 2;346(6283):485-8
references: 1974036
references: Genes Dev. 2007 Sep 1;21(17):2182-95
references: 17785526
references: Adv Exp Med Biol. 2008;628:82-101
references: 18683640
references: Nat Neurosci. 2003 Dec;6(12):1255-63
references: 14625556
references: Development. 1996 Dec;122(12):3893-8
references: 9012509
references: Mech Dev. 2004 May;121(5):475-89
references: 15147765
references: Development. 2005 Feb;132(4):725-37
references: 15659487
references: Development. 2010 Nov;137(21):3687-95
references: 20940227
references: Trends Neurosci. 2001 May;24(5):251-4
references: 11311363
references: Nature. 2001 Nov 8;414(6860):204-8
references: 11719930
references: J Neurosci. 1997 Jun 1;17(11):4243-52
references: 9151741
references: Development. 2008 Aug;135(14):2415-24
references: 18550709
references: Dev Biol. 1996 Jan 10;173(1):243-55
references: 8575625
references: Rouxs Arch Dev Biol. 1993 Jan;203(1-2):60-73
references: 28305981
references: Cell. 2010 Sep 3;142(5):679-81
references: 20813256
references: Mech Dev. 1996 Jul;57(2):169-80
references: 8843394
references: Proc Natl Acad Sci U S A. 2012 May 15;109(20):7893-8
references: 22547825
references: Philos Trans R Soc Lond B Biol Sci. 2008 Apr 27;363(1496):1523-8
references: 18192182
references: Prog Neurobiol. 2001 May;64(1):69-95
references: 11250063
references: Philos Trans R Soc Lond B Biol Sci. 2001 Oct 29;356(1414):1533-44
references: 11604121
references: Proc Natl Acad Sci U S A. 2004 Apr 27;101(17):6536-41
references: 15084738
references: Development. 1997 Dec;124(23):4793-800
references: 9428415
references: Development. 1998 Nov;125(21):4185-93
references: 9753673
references: Rouxs Arch Dev Biol. 1995 Sep;205(1-2):31-44
references: 28306063
references: Chem Senses. 2008 Nov;33(9):825-37
references: 18854508
references: Development. 2008 Sep;135(17):2883-93
references: 18653555
references: Cell Tissue Res. 1993 Sep;273(3):583-98
references: 8402833
references: J Neurosci. 2012 Apr 18;32(16):5426-39
references: 22514306
references: Nature. 1990 Aug 2;346(6283):482-5
references: 1974035
references: Dev Cell. 2003 Sep;5(3):391-402
references: 12967559
references: Development. 1995 Nov;121(11):3561-72
references: 8582270