title: Hc-daf-2 encodes an insulin-like receptor kinase in the barber's pole worm, Haemonchus contortus, and restores partial dauer regulation.
abstract: Infective L3s (iL3s) of parasitic nematodes share common behavioural, morphological and developmental characteristics with the developmentally arrested (dauer) larvae of the free-living nematode Caenorhabditis elegans. It is proposed that similar molecular mechanisms regulate entry into or exit from the dauer stage in C. elegans, and the transition from free-living to parasitic forms of parasitic nematodes. In C. elegans, one of the key factors regulating the dauer transition is the insulin-like receptor (designated Ce-DAF-2) encoded by the gene Ce-daf-2. However, nothing is known about DAF-2 homologues in most parasitic nematodes. Here, using a PCR-based approach, we identified and characterised a gene (Hc-daf-2) and its inferred product (Hc-DAF-2) in Haemonchus contortus (a socioeconomically important parasitic nematode of ruminants). The sequence of Hc-DAF-2 displays significant sequence homology to insulin receptors (IR) in both vertebrates and invertebrates, and contains conserved structural domains. A sequence encoding an important proteolytic motif (RKRR) identified in the predicted peptide sequence of Hc-DAF-2 is consistent with that of the human IR, suggesting that it is involved in the formation of the IR complex. The Hc-daf-2 gene was transcribed in all life stages of H. contortus, with a significant up-regulation in the iL3 compared with other stages. To compare patterns of expression between Hc-daf-2 and Ce-daf-2, reporter constructs fusing the Ce-daf-2 or Hc-daf-2 promoter to sequence encoding GFP were microinjected into the N2 strain of C. elegans, and transgenic lines were established and examined. Both genes showed similar patterns of expression in amphidial (head) neurons, which relate to sensation and signal transduction. Further study by heterologous genetic complementation in a daf-2-deficient strain of C. elegans (CB1370) showed partial rescue of function by Hc-daf-2. Taken together, these findings provide a first insight into the roles of Hc-daf-2/Hc-DAF-2 in the biology and development of H. contortus, particularly in the transition to parasitism.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, College of Veterinary Medicine, Huazhong Agricultural University, 1 Shizishan Street, Wuhan 430070, Hubei, China.
authors.forename: Facai
authors.initials: F
authors.lastname: Li
authors.affiliation: Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, 3800 Spruce Street, Philadelphia, PA 19104, USA.
authors.forename: James B
authors.initials: JB
authors.lastname: Lok
authors.affiliation: Faculty of Veterinary Science, The University of Melbourne, Corner of Flemington Road and Park Drive, Parkville, Victoria 3010, Australia; Institute of Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, 16-18 Kaiserswerther Street, Berlin 14195, Germany.
authors.forename: Robin B
authors.initials: RB
authors.lastname: Gasser
authors.affiliation: Faculty of Veterinary Science, The University of Melbourne, Corner of Flemington Road and Park Drive, Parkville, Victoria 3010, Australia.
authors.forename: Pasi K
authors.initials: PK
authors.lastname: Korhonen
authors.affiliation: School of Applied Sciences and Engineering, Monash University, Northways Road, Churchill, Victoria 3842, Australia.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Sandeman
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, College of Veterinary Medicine, Huazhong Agricultural University, 1 Shizishan Street, Wuhan 430070, Hubei, China.
authors.forename: Deshi
authors.initials: D
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, College of Veterinary Medicine, Huazhong Agricultural University, 1 Shizishan Street, Wuhan 430070, Hubei, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhou
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, Jiangsu, China.
authors.forename: Xiangrui
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, College of Veterinary Medicine, Huazhong Agricultural University, 1 Shizishan Street, Wuhan 430070, Hubei, China.
authors.forename: Yanqin
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, College of Veterinary Medicine, Huazhong Agricultural University, 1 Shizishan Street, Wuhan 430070, Hubei, China.
authors.forename: Junlong
authors.initials: J
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, College of Veterinary Medicine, Huazhong Agricultural University, 1 Shizishan Street, Wuhan 430070, Hubei, China. Electronic address: mhu@mail.hzau.edu.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Hu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D005075:Biological Evolution; D017173:Caenorhabditis elegans; D018076:DNA, Complementary / Q000235:genetics; D018509:DNA, Helminth / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D005816:Genetic Complementation Test; D006189:Haemonchus / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D015801:Helminth Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D018510:RNA, Helminth / Q000235:genetics
chemical_list: D018076:DNA, Complementary; D018509:DNA, Helminth; D015801:Helminth Proteins; D018510:RNA, Helminth
keywords: Development; Haemonchus contortus; Parasitic nematode; Transgenesis; daf-2
references.citation: FASEB J. 1995 May;9(8):576-96
references.pmid: 7768349
references.citation: Trends Parasitol. 2001 Aug;17(8):387-93
references.pmid: 11685900
references.citation: Mol Cell. 1998 Dec;2(6):887-93
references.pmid: 9885576
references.citation: WormBook. 2006 Feb 11;:1-11
references.pmid: 18050451
references.citation: Nucleic Acids Res. 1994 Nov 11;22(22):4673-80
references.pmid: 7984417
references.citation: J Cell Biol. 1998 May 4;141(3):637-46
references.pmid: 9566965
references.citation: Development. 2011 Mar;138(6):1183-93
references.pmid: 21343369
references.citation: PLoS Pathog. 2009 Apr;5(4):e1000370
references.pmid: 19360119
references.citation: Mol Endocrinol. 1996 Jul;10(7):857-66
references.pmid: 8813726
references.citation: EMBO J. 1996 Apr 1;15(7):1495-506
references.pmid: 8612572
references.citation: Int J Parasitol. 2010 Jan;40(1):1-13
references.pmid: 19932111
references.citation: PLoS One. 2011 Mar 22;6(3):e18086
references.pmid: 21445366
references.citation: Trends Parasitol. 2007 May;23(5):197-204
references.pmid: 17383233
references.citation: WormBook. 2006 Oct 25;:1-29
references.pmid: 18050433
references.citation: Vet Parasitol. 2005 Mar 31;128(3-4):285-90
references.pmid: 15740865
references.citation: Parasitol Today. 1993 Jan;9(1):23-6
references.pmid: 15463660
references.citation: J Biol Chem. 1992 Aug 15;267(23):16660-8
references.pmid: 1322912
references.citation: Int J Parasitol. 2009 Mar;39(4):407-15
references.pmid: 18930062
references.citation: Int J Parasitol. 2003 Nov;33(13):1537-44
references.pmid: 14572516
references.citation: Neuron. 1991 Nov;7(5):729-42
references.pmid: 1660283
references.citation: Parasitology. 1993 Feb;106 ( Pt 2):163-9
references.pmid: 8446471
references.citation: Nucleic Acids Res. 2000 Nov 1;28(21):4364-75
references.pmid: 11058137
references.citation: Genetics. 1998 Sep;150(1):129-55
references.pmid: 9725835
references.citation: Science. 2007 Sep 21;317(5845):1756-60
references.pmid: 17885136
references.citation: FASEB J. 2012 Nov;26(11):4650-61
references.pmid: 22889830
references.citation: EMBO J. 1997 Sep 15;16(18):5572-81
references.pmid: 9312016
references.citation: Neuron. 1996 Oct;17(4):719-28
references.pmid: 8893028
references.citation: Annu Rev Biochem. 1981;50:349-83
references.pmid: 6791577
references.citation: Int J Parasitol. 2013 Jun;43(7):515-20
references.pmid: 23500073
references.citation: Mol Biochem Parasitol. 1996 Apr;77(1):77-93
references.pmid: 8784774
references.citation: Methods Mol Biol. 2011;772:459-70
references.pmid: 22065455
references.citation: Dev Biol. 1984 Apr;102(2):368-78
references.pmid: 6706004
references.citation: BMC Genomics. 2010 Apr 27;11:266
references.pmid: 20420710
references.citation: Int J Parasitol. 2006 Mar;36(3):347-52
references.pmid: 16442538
references.citation: Int J Parasitol. 2010 Dec;40(14):1619-28
references.pmid: 20654619
references.citation: Int J Parasitol. 2003 Sep 30;33(11):1259-68
references.pmid: 13678640
references.citation: Science. 1998 Dec 11;282(5396):2041-6
references.pmid: 9851921
references.citation: Genome Biol. 2013 Aug 28;14(8):R89
references.pmid: 23985341
references.citation: Genes Dev. 2002 Dec 1;16(23):3061-73
references.pmid: 12464635
references.citation: Genome Biol. 2013 Aug 28;14(8):R88
references.pmid: 23985316
references.citation: Trends Parasitol. 2011 Nov;27(11):505-13
references.pmid: 21885343
references.citation: Vet Parasitol. 2012 Sep 30;189(1):85-8
references.pmid: 22503039
references.citation: EMBO J. 1996 Jun 17;15(12):2961-8
references.pmid: 8670797
references.citation: Parasitology. 2007;134(Pt 8):1133-47
references.pmid: 17608973
references.citation: J Am Vet Med Assoc. 1962 Sep 15;141:706-9
references.pmid: 13881890
references.citation: Aging Cell. 2009 Dec;8(6):706-25
references.pmid: 19764929
references.citation: Lancet. 2009 May 2;373(9674):1570-5
references.pmid: 19410718
references.citation: Mol Biol Evol. 2011 Oct;28(10):2731-9
references.pmid: 21546353
references.citation: Cell. 1984 Nov;39(1):27-38
references.pmid: 6091915
references.citation: Antioxid Redox Signal. 2011 Feb 15;14(4):623-34
references.pmid: 20673162
references.citation: Science. 1997 Nov 14;278(5341):1319-22
references.pmid: 9360933
references.citation: Cell. 1988 Aug 26;54(5):641-9
references.pmid: 2842060
references.citation: Nature. 1997 Oct 30;389(6654):994-9
references.pmid: 9353126
references.citation: Genome Res. 2010 Dec;20(12):1740-7
references.pmid: 20980554
references.citation: J Parasitol. 1999 Jun;85(3):397-403
references.pmid: 10386428
references.citation: Trends Parasitol. 2004 Oct;20(10):469-76
references.pmid: 15363440
references.citation: Genes Dev. 2003 Apr 1;17(7):844-58
references.pmid: 12654727
references.citation: J Biol Chem. 1995 Mar 3;270(9):4236-43
references.pmid: 7876183
references.citation: J Biol Chem. 1994 Oct 14;269(41):25830-7
references.pmid: 7929288
references.citation: Int J Neural Syst. 1997 Oct-Dec;8(5-6):581-99
references.pmid: 10065837
references.citation: Int J Parasitol. 2006 May 31;36(6):651-9
references.pmid: 16616144
references.citation: Science. 2002 Feb 1;295(5556):821-5
references.pmid: 11823633
references.citation: EMBO J. 1991 Dec;10(12):3959-70
references.pmid: 1935914
references.citation: Genes Dev. 2001 Mar 15;15(6):672-86
references.pmid: 11274053
references.citation: Nat Biotechnol. 2007 Jun;25(6):663-8
references.pmid: 17486083
references.citation: Nat Genet. 2014 Mar;46(3):261-269
references.pmid: 24441737
references.citation: PLoS Biol. 2007 Sep;5(9):e237
references.pmid: 17850180
references.citation: Nature. 2001 Apr 5;410(6829):698-701
references.pmid: 11287957
references.citation: J Biol Chem. 1994 Jan 7;269(1):1-4
references.pmid: 8276779
references.citation: Nat Genet. 2013 May;45(5):495-500
references.pmid: 23525074
references.citation: PLoS Pathog. 2012;8(8):e1002871
references.pmid: 22912584
references.citation: Int J Parasitol. 2010 Mar 15;40(4):405-15
references.pmid: 19796644
references.citation: Nature. 2011 Oct 26;479(7374):529-33
references.pmid: 22031327
references.citation: Int J Parasitol. 2010 Dec;40(14):1675-83
references.pmid: 20673766
references.citation: Int J Parasitol. 1998 Mar;28(3):395-411
references.pmid: 9559358
references.citation: PLoS One. 2011;6(10):e25996
references.pmid: 22016799
references.citation: Biochem Biophys Res Commun. 1991 Jun 28;177(3):1013-8
references.pmid: 1647764
references.citation: Cold Spring Harb Symp Quant Biol. 2011;76:113-20
references.pmid: 22123849
references.citation: Infect Immun. 2000 Jun;68(6):3491-501
references.pmid: 10816503
references.citation: PLoS One. 2012;7(6):e38587
references.pmid: 22701676
references.citation: Trends Biochem Sci. 1997 Jul;22(7):267-72
references.pmid: 9255069
references.citation: PLoS Negl Trop Dis. 2012;6(10):e1854
references.pmid: 23145190
references.citation: Nature. 1984 Feb 9-15;307(5951):521-7
references.pmid: 6320011
references.citation: Int J Parasitol. 2004 Jul;34(8):909-14
references.pmid: 15217729
references.citation: Nature. 1985 Feb 28-Mar 6;313(6005):756-61
references.pmid: 2983222
references.citation: Mol Cell Biol. 1995 May;15(5):2500-8
references.pmid: 7537849
references.citation: Science. 1997 Aug 15;277(5328):942-6
references.pmid: 9252323
references.citation: Parasitology. 2004;128 Suppl 1:S49-70
references.pmid: 16454899
references.citation: Int J Parasitol. 2003 Mar;33(3):301-12
references.pmid: 12670515
references.citation: Nature. 1998 Mar 5;392(6671):71-5
references.pmid: 9510248
references.citation: Cell. 1998 Oct 16;95(2):199-210
references.pmid: 9790527
references.citation: J Biol Chem. 1997 Nov 21;272(47):29460-7
references.pmid: 9368005
references.citation: Diabetologia. 1992 Mar;35(3):261-6
references.pmid: 1563582
references.citation: Nat Rev Genet. 2006 Aug;7(8):606-19
references.pmid: 16847462
references.citation: Trends Parasitol. 2007 Mar;23(3):105-7
references.pmid: 17276139
references.citation: Exp Gerontol. 2006 Oct;41(10):928-34
references.pmid: 16839734
references.citation: Trends Parasitol. 2004 Oct;20(10):477-81
references.pmid: 15363441
references.citation: Trends Parasitol. 2004 Apr;20(4):178-84
references.pmid: 15099557