title: The avian proghrelin system.
abstract: To understand how the proghrelin system functions in regulating growth hormone release and food intake as well as defining its pleiotropic roles in such diverse physiological processes as energy homeostasis, gastrointestinal tract function and reproduction require detailed knowledge of the structure and function of the components that comprise this system. These include the preproghrelin gene that encodes the proghrelin precursor protein from which two peptide hormones, ghrelin and obestatin, are derived and the cognate receptors that bind proghrelin-derived peptides to mediate their physiological actions in different tissues. Also key to the functioning of this system is the posttranslational processing of the proghrelin precursor protein and the individual peptides derived from it. While this system has been intensively studied in a variety of animal species and humans over the last decade, there has been considerably less investigation of the avian proghrelin system which exhibits some unique differences compared to mammals. This review summarizes what is currently known about the proghrelin system in birds and offers new insights into the nature and function of this important endocrine system. Such information facilitates cross-species comparisons and contributes to our understanding of the evolution of the proghrelin system.
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Animal Biosciences and Biotechnology Laboratory, Beltsville Agricultural Research Center, Animal and Natural Resources Institute, Beltsville, MD 20705-2350, USA.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Richards
authors.forename: John P
authors.initials: JP
authors.lastname: McMurtry
references.citation: Proc Natl Acad Sci U S A. 2008 Apr 29;105(17):6320-5
references.pmid: 18443287
references.citation: Peptides. 2007 Mar;28(3):617-24
references.pmid: 17145117
references.citation: Gen Comp Endocrinol. 2005 Apr;141(2):178-83
references.pmid: 15748719
references.citation: Nat Med. 2009 Jul;15(7):741-5
references.pmid: 19503064
references.citation: Eur J Pharmacol. 2002 Oct 18;453(1):75-9
references.pmid: 12393062
references.citation: Domest Anim Endocrinol. 2006 Feb;30(2):108-16
references.pmid: 16054797
references.citation: Peptides. 2008 Jul;29(7):1255-70
references.pmid: 18396350
references.citation: Peptides. 2009 Jul;30(7):1342-7
references.pmid: 19409434
references.citation: Endocrinology. 2001 Sep;142(9):4154-7
references.pmid: 11517195
references.citation: Endocrinology. 2004 Sep;145(9):4144-53
references.pmid: 15142980
references.citation: Neurosci Lett. 2006 Sep 25;405(3):241-5
references.pmid: 16901639
references.citation: Endocrinology. 2002 Sep;143(9):3454-63
references.pmid: 12193558
references.citation: Life Sci. 2004 Sep 17;75(18):2193-201
references.pmid: 15325845
references.citation: Vet Res Commun. 2004 Aug;28 Suppl 1:213-5
references.pmid: 15372960
references.citation: Nature. 1999 Dec 9;402(6762):656-60
references.pmid: 10604470
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2008 Feb;149(2):109-28
references.pmid: 18222718
references.citation: J Biol Chem. 2003 Jan 3;278(1):64-70
references.pmid: 12414809
references.citation: J Biol Chem. 2000 Jul 21;275(29):21995-2000
references.pmid: 10801861
references.citation: Regul Pept. 2009 Apr 10;154(1-3):97-101
references.pmid: 19232371
references.citation: Growth Dev Aging. 2004 Summer;68(1):3-10
references.pmid: 15307660
references.citation: Domest Anim Endocrinol. 2007 Apr;32(3):216-25
references.pmid: 16766157
references.citation: Regul Pept. 2003 Mar 28;111(1-3):123-8
references.pmid: 12609759
references.citation: Science. 1996 Aug 16;273(5277):974-7
references.pmid: 8688086
references.citation: Gen Comp Endocrinol. 2008 Apr 1;156(2):323-38
references.pmid: 18299131
references.citation: Gen Comp Endocrinol. 2009 Sep 1;163(1-2):39-46
references.pmid: 18938167
references.citation: Science. 2005 Nov 11;310(5750):996-9
references.pmid: 16284174
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2007 May;147(1):239-46
references.pmid: 17293148
references.citation: J Biol Chem. 2006 Dec 15;281(50):38867-70
references.pmid: 17050541
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2007 Aug;147(4):893-902
references.pmid: 17376723
references.citation: Biochem Genet. 2007 Apr;45(3-4):185-94
references.pmid: 17347866
references.citation: Physiol Rev. 2005 Apr;85(2):495-522
references.pmid: 15788704
references.citation: Acta Histochem. 2005;107(1):3-9
references.pmid: 15866281
references.citation: Biochem Biophys Res Commun. 2005 Jul 29;333(2):583-9
references.pmid: 15953586
references.citation: Br Poult Sci. 2004 Oct;45(5):611-8
references.pmid: 15623213
references.citation: Gen Comp Endocrinol. 2006 Feb;145(3):298-310
references.pmid: 16253250
references.citation: BMC Genomics. 2007 Aug 30;8:298
references.pmid: 17727735
references.citation: Domest Anim Endocrinol. 2008 Feb;34(2):125-34
references.pmid: 17207955
references.citation: Gen Comp Endocrinol. 2009 Sep 1;163(1-2):33-8
references.pmid: 19056391
references.citation: Gen Comp Endocrinol. 2003 Nov;134(2):167-74
references.pmid: 14511987
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2008 Mar;149(3):325-9
references.pmid: 18280762
references.citation: Mol Cell Endocrinol. 2006 Sep 26;257-258:15-25
references.pmid: 16891055
references.citation: Poult Sci. 2007 Nov;86(11):2472-6
references.pmid: 17954600
references.citation: Gen Comp Endocrinol. 2003 Nov;134(2):198-202
references.pmid: 14511992
references.citation: Mol Biol Rep. 2010 Jan;37(1):423-8
references.pmid: 19437137
references.citation: Neurobiol Learn Mem. 2009 May;91(4):402-7
references.pmid: 19146965
references.citation: J Endocrinol. 2003 Oct;179(1):97-105
references.pmid: 14529570
references.citation: Peptides. 2009 May;30(5):991-4
references.pmid: 19428778
references.citation: Gen Comp Endocrinol. 2007 Mar;151(1):128-34
references.pmid: 17239877
references.citation: Neurosci Lett. 2001 Mar 30;301(2):123-6
references.pmid: 11248438
references.citation: J Biochem. 2009 Nov;146(5):675-82
references.pmid: 19628676
references.citation: Trends Endocrinol Metab. 2008 Dec;19(10):362-70
references.pmid: 18938086
references.citation: Regul Pept. 2005 Feb 15;125(1-3):201-8
references.pmid: 15582733
references.citation: Domest Anim Endocrinol. 2007 May;32(4):247-59
references.pmid: 16650710
references.citation: Cell. 2008 Feb 8;132(3):387-96
references.pmid: 18267071
references.citation: Biochem Biophys Res Commun. 2003 May 23;305(1):186-92
references.pmid: 12732215
references.citation: J Endocrinol. 2002 Jan;172(1):117-25
references.pmid: 11786379