title: A receptor-like kinase gene (GbRLK) from Gossypium barbadense enhances salinity and drought-stress tolerance in Arabidopsis.
abstract: BACKGROUND
  Cotton (Gossypium spp.) is widely cultivated due to the important economic value of its fiber. However, extreme environmental degradation impedes cotton growth and production. Receptor-like kinase (RLK) proteins play important roles in signal transduction and participate in a diverse range of processes in response to plant hormones and environmental cues. Here, we introduced an RLK gene (GbRLK) from cotton into Arabidopsis and investigated its role in imparting abiotic stress tolerance.
  
  
  RESULTS
  GbRLK transcription was induced by exogenously supplied abscisic acid (ABA), salicylic acid, methyl jasmonate, mock drought conditions and high salinity. We cloned the promoter sequence of this gene via self-formed adaptor PCR. Sequence analysis revealed that the promoter region contains many cis-acting stress-responsive elements such as ABRE, W-Box, MYB-core, W-Box core, TCA-element and others. We constructed a vector containing a 1,890-bp sequence in the 5' region upstream of the initiation codon of this promoter and transformed it into Arabidopsis thaliana. GUS histochemical staining analysis showed that GbRLK was expressed mainly in leaf veins, petioles and roots of transgenic Arabidopsis, but not in the cotyledons or root hairs. GbRLK promoter activity was induced by ABA, PEG, NaCl and Verticillium dahliae. Transgenic Arabidopsis with constitutive overexpression of GbRLK exhibited a reduced rate of water loss in leaves in vitro, along with improved salinity and drought tolerance and increased sensitivity to ABA compared with non-transgenic Col-0 Arabidopsis. Expression analysis of stress-responsive genes in GbRLK Arabidopsis revealed that there was increased expression of genes involved in the ABA-dependent signaling pathway (AtRD20, AtRD22 and AtRD26) and antioxidant genes (AtCAT1, AtCCS, AtCSD2 and AtCSD1) but not ion transporter genes (AtNHX1, AtSOS1).
  
  
  CONCLUSIONS
  GbRLK is involved in the drought and high salinity stresses pathway by activating or participating in the ABA signaling pathway. Overexpression of GbRLK may improve stress tolerance by regulating stress-responsive genes to reduce water loss. GbRLK may be employed in the genetic engineering of novel cotton cultivars in the future. Further studying of GbRLK will help elucidate abiotic stress signaling pathways.
authors.affiliation: National Key Laboratory of Crop Genetics & Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhao
authors.forename: Yulong
authors.initials: Y
authors.lastname: Gao
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Zhang
authors.forename: Tianzi
authors.initials: T
authors.lastname: Chen
authors.forename: Wangzhen
authors.initials: W
authors.lastname: Guo
authors.forename: Tianzhen
authors.initials: T
authors.lastname: Zhang
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D003368:Gossypium / Q000201:enzymology* / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000502:physiology*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D054712:Salinity; D012965:Sodium Chloride / Q000378:metabolism; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins; D010940:Plant Proteins; D012965:Sodium Chloride; D011494:Protein Kinases
references.citation: Plant Physiol. 1989 Nov;91(3):812-5
references.pmid: 16667141
references.citation: J Integr Plant Biol. 2008 Oct;50(10):1187-95
references.pmid: 19017106
references.citation: Science. 1993 Nov 26;262(5138):1432-6
references.pmid: 7902614
references.citation: Sci China C Life Sci. 2006 Dec;49(6):530-42
references.pmid: 17312991
references.citation: Proc Natl Acad Sci U S A. 2009 May 19;106(20):8380-5
references.pmid: 19420218
references.citation: EMBO J. 1987 Dec 20;6(13):3901-7
references.pmid: 3327686
references.citation: Arch Biochem Biophys. 2005 Dec 15;444(2):139-58
references.pmid: 16309626
references.citation: Plant Mol Biol. 2012 Feb;78(3):223-46
references.pmid: 22143977
references.citation: Plant Mol Biol. 1994 Dec;26(5):1599-609
references.pmid: 7858206
references.citation: Plant Cell. 2006 Aug;18(8):2051-65
references.pmid: 16861386
references.citation: Annu Rev Plant Biol. 2010;61:651-79
references.pmid: 20192755
references.citation: Nat Cell Biol. 2009 Oct;11(10):1254-60
references.pmid: 19734888
references.citation: Plant Cell. 2012 Jun;24(6):2546-61
references.pmid: 22730405
references.citation: Appl Environ Microbiol. 2007 Aug;73(15):5048-51
references.pmid: 17483260
references.citation: Mol Cell. 2000 Jun;5(6):1003-11
references.pmid: 10911994
references.citation: Mol Plant. 2009 Jul;2(4):675-687
references.pmid: 19825648
references.citation: Plant J. 1998 Dec;16(6):735-43
references.pmid: 10069079
references.citation: Sci STKE. 2001 Dec 18;2001(113):re22
references.pmid: 11752632
references.citation: Plant Cell. 2012 Jun;24(6):2262-78
references.pmid: 22693282
references.citation: BMC Plant Biol. 2011 Nov 17;11:163
references.pmid: 22094046
references.citation: Plant J. 2003 Oct;36(2):229-39
references.pmid: 14535887
references.citation: Anal Biochem. 1976 May 7;72:248-54
references.pmid: 942051
references.citation: Plant J. 2008 Nov;56(4):575-89
references.pmid: 18643966
references.citation: Science. 2008 Jul 25;321(5888):557-60
references.pmid: 18653891
references.citation: Plant Signal Behav. 2011 Nov;6(11):1741-5
references.pmid: 22057331
references.citation: J Exp Bot. 2009;60(2):591-602
references.pmid: 19098131
references.citation: J Biol Chem. 2010 Mar 19;285(12):9190-201
references.pmid: 20089852
references.citation: Nat Rev Mol Cell Biol. 2001 Apr;2(4):276-84
references.pmid: 11283725
references.citation: Comput Chem. 2001 Dec;26(1):51-6
references.pmid: 11765852
references.citation: Plant Cell Physiol. 2009 Jul;50(7):1345-63
references.pmid: 19541597
references.citation: Plant J. 2007 Apr;50(2):347-63
references.pmid: 17376166
references.citation: BMC Plant Biol. 2012 Oct 10;12:187
references.pmid: 23051937
references.citation: BMC Genomics. 2012 Mar 16;13:94
references.pmid: 22424186
references.citation: Mol Biol Rep. 2012 Feb;39(2):969-87
references.pmid: 21573796
references.citation: Plant J. 2010 Apr;62(2):316-29
references.pmid: 20128882
references.citation: Genes Dev. 2000 Jan 1;14(1):108-17
references.pmid: 10640280
references.citation: Plant Cell. 2001 Sep;13(9):2063-83
references.pmid: 11549764
references.citation: Proc Natl Acad Sci U S A. 2001 Sep 11;98(19):10763-8
references.pmid: 11526204
references.citation: Mol Gen Genet. 1993 Apr;238(1-2):17-25
references.pmid: 8479424
references.citation: Curr Opin Plant Biol. 2000 Jun;3(3):217-23
references.pmid: 10837265
references.citation: Plant Mol Biol. 1998 Jun;37(3):425-35
references.pmid: 9617810
references.citation: Plant J. 1997 Oct;12(4):791-804
references.pmid: 9375393
references.citation: Plant Cell. 2002 Feb;14(2):465-77
references.pmid: 11884687
references.citation: Trends Plant Sci. 2005 Feb;10(2):88-94
references.pmid: 15708346
references.citation: Plant J. 2004 Sep;39(6):863-76
references.pmid: 15341629
references.citation: Plant Cell. 2004 May;16(5):1220-34
references.pmid: 15105442
references.citation: Plant J. 2012 May;70(4):599-613
references.pmid: 22225700
references.citation: Methods. 2001 Dec;25(4):402-8
references.pmid: 11846609
references.citation: Science. 1995 Dec 15;270(5243):1804-6
references.pmid: 8525370
references.citation: Nucleic Acids Res. 2010 Oct;38(19):6513-25
references.pmid: 20542917
references.citation: Nucleic Acids Res. 1999 Jan 1;27(1):297-300
references.pmid: 9847208
references.citation: Plant Cell Physiol. 2010 Dec;51(12):1975-87
references.pmid: 20952421
references.citation: Biotechnol Lett. 2011 Apr;33(4):821-8
references.pmid: 21188619
references.citation: Nucleic Acids Res. 2002 Jan 1;30(1):325-7
references.pmid: 11752327
references.citation: Curr Opin Plant Biol. 2000 Oct;3(5):361-7
references.pmid: 11019802
references.citation: Plant Cell. 2011 May;23(5):1876-88
references.pmid: 21558544
references.citation: Plant Cell. 2002 Apr;14(4):749-62
references.pmid: 11971132