title: Shared and divergent pathways for flower abscission are triggered by gibberellic acid and carbon starvation in seedless Vitis vinifera L.
abstract: BACKGROUND
  Abscission is a highly coordinated developmental process by which plants control vegetative and reproductive organs load. Aiming at get new insights on flower abscission regulation, changes in the global transcriptome, metabolome and physiology were analyzed in 'Thompson Seedless' grapevine (Vitis vinifera L.) inflorescences, using gibberellic acid (GAc) spraying and shading as abscission stimuli, applied at bloom.
  
  
  RESULTS
  Natural flower drop rates increased from 63.1% in non-treated vines to 83% and 99% in response to GAc and shade treatments, respectively. Both treatments had a broad effect on inflorescences metabolism. Specific impacts from shade included photosynthesis inhibition, associated nutritional stress, carbon/nitrogen imbalance and cell division repression, whereas GAc spraying induced energetic metabolism simultaneously with induction of nucleotide biosynthesis and carbon metabolism, therefore, disclosing alternative mechanisms to regulate abscission. Regarding secondary metabolism, changes in flavonoid metabolism were the most represented metabolic pathways in the samples collected following GAc treatment while phenylpropanoid and stilbenoid related pathways were predominantly affected in the inflorescences by the shade treatment. However, both GAc and shade treated inflorescences revealed also shared pathways, that involved the regulation of putrescine catabolism, the repression of gibberellin biosynthesis, the induction of auxin biosynthesis and the activation of ethylene signaling pathways and antioxidant mechanisms, although often the quantitative changes occurred on specific transcripts and metabolites of the pathways.
  
  
  CONCLUSIONS
  Globally, the results suggest that chemical and environmental cues induced contrasting effects on inflorescence metabolism, triggering flower abscission by different mechanisms and pinpointing the participation of novel abscission regulators. Grapevine showed to be considered a valid model to study molecular pathways of flower abscission competence acquisition, noticeably responding to independent stimuli.
authors.affiliation: Linking Landscape, Environment, Agriculture and Food (LEAF), Instituto Superior de Agronomia (ISA), Universidade de Lisboa (ULisboa), Lisbon, Portugal. saradomingos@isa.ulisboa.pt.|Instituto de Investigação Científica Tropical, I.P. (IICT), Lisbon, Portugal. saradomingos@isa.ulisboa.pt.
authors.forename: Sara
authors.initials: S
authors.lastname: Domingos
authors.affiliation: Instituto de Investigação Científica Tropical, I.P. (IICT), Lisbon, Portugal. joana.fino@gmail.com.|Computational Biology and Population Genomics Group, Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal. joana.fino@gmail.com.
authors.forename: Joana
authors.initials: J
authors.lastname: Fino
authors.affiliation: Instituto de Investigação Científica Tropical, I.P. (IICT), Lisbon, Portugal. vaniaalexandracardoso@gmail.com.
authors.forename: Vânia
authors.initials: V
authors.lastname: Cardoso
authors.affiliation: Instituto Nacional de Investigação Agrária e Veterinária, I.P. (INIAV), Oeiras, Portugal. claudia.sanchez@iniav.pt.
authors.forename: Claudia
authors.initials: C
authors.lastname: Sánchez
authors.affiliation: Linking Landscape, Environment, Agriculture and Food (LEAF), Instituto Superior de Agronomia (ISA), Universidade de Lisboa (ULisboa), Lisbon, Portugal. cochichor@mail.telepac.pt.|Instituto de Investigação Científica Tropical, I.P. (IICT), Lisbon, Portugal. cochichor@mail.telepac.pt.|GeoBioTec, Faculdade de Ciências e Tecnolgia (FCT), Universidade Nova de Lisboa (UNL), Caparica, Portugal. cochichor@mail.telepac.pt.
authors.forename: José C
authors.initials: JC
authors.lastname: Ramalho
authors.affiliation: FEM-IASMA, Fondazione Edmund Mach, Istituto Agrario di San Michele all'Adige, San Michele all'Adige, TN, Italy. roberto.larcher@fmach.it.
authors.forename: Roberto
authors.initials: R
authors.lastname: Larcher
authors.affiliation: Computational Biology and Population Genomics Group, Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal. ofpaulo@fc.ul.pt.
authors.forename: Octávio S
authors.initials: OS
authors.lastname: Paulo
authors.affiliation: Linking Landscape, Environment, Agriculture and Food (LEAF), Instituto Superior de Agronomia (ISA), Universidade de Lisboa (ULisboa), Lisbon, Portugal. crismoniz@isa.ulisboa.pt.
authors.forename: Cristina M
authors.initials: CM
authors.lastname: Oliveira
authors.affiliation: Instituto de Investigação Científica Tropical, I.P. (IICT), Lisbon, Portugal. goulao@reitoria.ulisboa.pt.|Present address: Colégio Food, Farming and Forestry, Universidade de Lisboa (ULisboa), Lisbon, Portugal. goulao@reitoria.ulisboa.pt.
authors.forename: Luis F
authors.initials: LF
authors.lastname: Goulao
mesh_terms: D002244:Carbon / Q000378:metabolism*; D035264:Flowers / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D017343:Genes, Plant; D005875:Gibberellins / Q000494:pharmacology*; D055442:Metabolome; D018515:Plant Leaves / Q000378:metabolism; D018749:RNA, Plant; D012639:Seeds; D059467:Transcriptome; D027843:Vitis / Q000235:genetics / Q000502:physiology*
chemical_list: D005875:Gibberellins; D018749:RNA, Plant; D002244:Carbon; C007842:gibberellic acid
references.citation: Nature. 2007 Sep 27;449(7161):463-7
references.pmid: 17721507
references.citation: Plant Signal Behav. 2009 Jun;4(6):493-6
references.pmid: 19816125
references.citation: J Exp Bot. 2005 Nov;56(421):2995-3005
references.pmid: 16203755
references.citation: Plant Cell Environ. 2010 Nov;33(11):1828-37
references.pmid: 20545885
references.citation: Ann Bot. 2007 Jun;99(6):1195-202
references.pmid: 17470901
references.citation: Prog Lipid Res. 2007 Jan;46(1):37-55
references.pmid: 16970991
references.citation: Plant J. 2011 Oct;68(1):168-85
references.pmid: 21689171
references.citation: Nature. 2007 Aug 23;448(7156):938-42
references.pmid: 17671505
references.citation: Plant Physiol. 2013 May;162(1):96-106
references.pmid: 23509178
references.citation: BMC Plant Biol. 2013 Mar 09;13:40
references.pmid: 23497084
references.citation: Plant Physiol. 2001 Jun;126(2):494-500
references.pmid: 11402180
references.citation: Plant Sci. 2013 Feb;199-200:48-60
references.pmid: 23265318
references.citation: Planta. 2000 Mar;210(4):636-43
references.pmid: 10787058
references.citation: J Exp Bot. 2004 Sep;55(405):2099-109
references.pmid: 15310825
references.citation: Annu Rev Plant Biol. 2002;53:27-43
references.pmid: 12221976
references.citation: BMC Bioinformatics. 2003 Sep 11;4:41
references.pmid: 12969510
references.citation: J Exp Bot. 2011 Aug;62(13):4447-65
references.pmid: 21633085
references.citation: Trends Plant Sci. 2009 May;14(5):255-63
references.pmid: 19362511
references.citation: Nat Biotechnol. 2010 May;28(5):511-5
references.pmid: 20436464
references.citation: J Exp Bot. 2014 Mar;65(3):799-807
references.pmid: 24453229
references.citation: J Exp Bot. 2015 Mar;66(5):1355-68
references.pmid: 25504336
references.citation: BMC Genomics. 2015 Feb 25;16:128
references.pmid: 25888129
references.citation: Front Plant Sci. 2015 Jun 22;6:457
references.pmid: 26157448
references.citation: Bioinformatics. 2014 Aug 1;30(15):2114-20
references.pmid: 24695404
references.citation: Genome Biol. 2014;15(12):550
references.pmid: 25516281
references.citation: Plant Physiol. 2010 Oct;154(2):567-70
references.pmid: 20921186
references.citation: New Phytol. 2013 Jan;197(2):490-502
references.pmid: 23253334
references.citation: PLoS One. 2015 Mar 16;10(3):e0115349
references.pmid: 25775459
references.citation: Anal Chem. 2009 Aug 15;81(16):6656-67
references.pmid: 19624122
references.citation: Plant Physiol. 2005 Nov;139(3):1350-65
references.pmid: 16258012
references.citation: Plant Signal Behav. 2011 Apr;6(4):590-3
references.pmid: 21543890
references.citation: FEBS Lett. 2007 May 25;581(12):2318-24
references.pmid: 17379213
references.citation: Proc Natl Acad Sci U S A. 2008 Oct 7;105(40):15629-34
references.pmid: 18809915
references.citation: Phytochemistry. 2011 Jun;72(9):838-43
references.pmid: 21440919
references.citation: J Exp Bot. 2012 Feb;63(4):1593-608
references.pmid: 22291134
references.citation: Plant Cell. 2009 Jan;21(1):131-45
references.pmid: 19151223
references.citation: Plant Signal Behav. 2008 Nov;3(11):1014-5
references.pmid: 19704438
references.citation: Crit Rev Biochem Mol Biol. 2000;35(4):291-314
references.pmid: 11005203
references.citation: Curr Opin Plant Biol. 2012 Dec;15(6):670-6
references.pmid: 23047135
references.citation: J Exp Bot. 2011 Oct;62(14):5091-103
references.pmid: 21765161
references.citation: Plant Physiol. 2013 Jul;162(3):1720-32
references.pmid: 23735508
references.citation: Nucleic Acids Res. 2013 Jan;41(Database issue):D590-6
references.pmid: 23193283
references.citation: Plant Physiol. 2013 Apr;161(4):1952-69
references.pmid: 23444344
references.citation: J Exp Bot. 2005 Jul;56(417):1867-75
references.pmid: 15928018
references.citation: Plant J. 2008 Jun;54(6):993-1003
references.pmid: 18298669
references.citation: Curr Opin Plant Biol. 2002 Aug;5(4):325-31
references.pmid: 12179966
references.citation: Plant Physiol. 2010 Dec;154(4):1929-56
references.pmid: 20947671
references.citation: J Agric Food Chem. 2012 Mar 21;60(11):2793-8
references.pmid: 22369364
references.citation: BMC Plant Biol. 2011 Oct 17;11:138
references.pmid: 22003957
references.citation: Plant Cell Environ. 2012 Oct;35(10):1769-86
references.pmid: 22620982
references.citation: Annu Rev Plant Biol. 2002;53:247-73
references.pmid: 12221975
references.citation: New Phytol. 2014 Jan;201(2):388-402
references.pmid: 24033322
references.citation: J Exp Bot. 2013 Nov;64(14):4403-19
references.pmid: 24006417
references.citation: Bioinformatics. 2005 Sep 15;21(18):3674-6
references.pmid: 16081474
references.citation: Plant Mol Biol. 2013 Feb;81(3):297-307
references.pmid: 23242919
references.citation: PLoS One. 2013;8(2):e55238
references.pmid: 23390523
references.citation: Amino Acids. 2010 Oct;39(4):933-47
references.pmid: 20186554
references.citation: J Exp Bot. 2015 Apr;66(7):1707-19
references.pmid: 25711702
references.citation: Plant Sci. 2014 Dec;229:215-224
references.pmid: 25443848
references.citation: J Biosci. 2005 Dec;30(5):761-76
references.pmid: 16388148
references.citation: BMC Genomics. 2013 Aug 14;14:552
references.pmid: 23941440
references.citation: Plant Cell Environ. 2013 Jul;36(7):1242-55
references.pmid: 23305614
references.citation: Development. 2013 Mar;140(6):1147-51
references.pmid: 23444347
references.citation: Physiol Plant. 2012 May;145(1):52-66
references.pmid: 21988125
references.citation: AoB Plants. 2012;2012:pls035
references.pmid: 23585923
references.citation: Genome Biol. 2013 Apr 25;14(4):R36
references.pmid: 23618408
references.citation: Bioinformatics. 2012 Jan 1;28(1):125-6
references.pmid: 22039206
references.citation: Nucleic Acids Res. 2008 Jan;36(Database issue):D480-4
references.pmid: 18077471
references.citation: Bioinformatics. 2006 Jun 15;22(12):1540-2
references.pmid: 16595560
references.citation: Annu Rev Plant Biol. 2008;59:225-51
references.pmid: 18173378
references.citation: J Exp Bot. 2014 Jul;65(12):3111-9
references.pmid: 24744429
references.citation: Plant Dis. 2011 Mar;95(3):269-278
references.pmid: 30743507
references.citation: BMC Genomics. 2013 Jan 17;14:37
references.pmid: 23327667
references.citation: Plant J. 2008 Oct;56(2):219-227
references.pmid: 18643977
references.citation: Plant Physiol. 2011 Jan;155(1):185-208
references.pmid: 21037112
references.citation: Trends Plant Sci. 2008 Sep;13(9):474-82
references.pmid: 18701338
references.citation: Trends Plant Sci. 2012 Nov;17(11):656-65
references.pmid: 22776090
references.citation: Plant Cell Environ. 2007 Sep;30(9):1041-51
references.pmid: 17661746
references.citation: J Cheminform. 2010 Oct 18;2(1):9
references.pmid: 20955607
references.citation: Plant Physiol. 1997 Jun;114(2):445-454
references.pmid: 12223719
references.citation: J Exp Bot. 2003 Jan;54(381):355-63
references.pmid: 12493864
references.citation: J Exp Bot. 2008;59(10):2565-78
references.pmid: 18508810
references.citation: Front Plant Sci. 2013 Mar 12;4:44
references.pmid: 23487525
references.citation: Plant Cell Environ. 2014 Apr;37(4):1022-36
references.pmid: 24182190
references.citation: J Plant Physiol. 2010 Nov 15;167(17):1432-41
references.pmid: 20643493
references.citation: Curr Opin Biotechnol. 2015 Aug;34:153-61
references.pmid: 25617827
references.citation: Plant Cell Physiol. 2007 Feb;48(2):287-98
references.pmid: 17205969
references.citation: Plant Physiol. 2012 Apr;158(4):1728-44
references.pmid: 22345506