title: Conservation and divergence of circadian clock operation in a stress-inducible Crassulacean acid metabolism species reveals clock compensation against stress.
abstract: One of the best-characterized physiological rhythms in plants is the circadian rhythm of CO(2) metabolism in Crassulacean acid metabolism (CAM) plants, which is the focus here. The central components of the plant circadian clock have been studied in detail only in Arabidopsis (Arabidopsis thaliana). Full-length cDNAs have been obtained encoding orthologs of CIRCADIAN CLOCK-ASSOCIATED1 (CCA1)/LATE ELONGATED HYPOCOTYL (LHY), TIMING OF CAB EXPRESSION1 (TOC1), EARLY FLOWERING4 (ELF4), ZEITLUPE (ZTL), FLAVIN-BINDING KELCH REPEAT F-BOX1 (FKF1), EARLY FLOWERING3 (ELF3), and a partial cDNA encoding GIGANTEA in the model stress-inducible CAM plant, Mesembryanthemum crystallinum (Common Ice Plant). TOC1 and LHY/CCA1 are under reciprocal circadian control in a manner similar to their regulation in Arabidopsis. ELF4, FKF1, ZTL, GIGANTEA, and ELF3 are under circadian control in C(3) and CAM leaves. ELF4 transcripts peak in the evening and are unaffected by CAM induction. FKF1 shows an abrupt transcript peak 3 h before subjective dusk. ELF3 transcripts appear in the evening, consistent with their role in gating light input to the circadian clock. Intriguingly, ZTL transcripts do not oscillate in Arabidopsis, but do in M. crystallinum. The transcript abundance of the clock-associated genes in M. crystallinum is largely unaffected by development and salt stress, revealing compensation of the central circadian clock against development and abiotic stress in addition to the well-known temperature compensation. Importantly, the clock in M. crystallinum is very similar to that in Arabidopsis, indicating that such a clock could control CAM without requiring additional components of the central oscillator or a novel CAM oscillator.
authors.affiliation: Department of Biology, University of York, York YO10 5YW, United Kingdom.
authors.forename: Susanna F
authors.initials: SF
authors.lastname: Boxall
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Foster
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Bohnert
authors.forename: John C
authors.initials: JC
authors.lastname: Cushman
authors.forename: Hugh G
authors.initials: HG
authors.lastname: Nimmo
authors.forename: James
authors.initials: J
authors.lastname: Hartwell
mesh_terms: D002940:Circadian Rhythm / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D014644:Genetic Variation; D035723:Mesembryanthemum / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D018384:Oxidative Stress; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D010940:Plant Proteins
references.citation: Nature. 2000 Dec 7;408(6813):716-20
references.pmid: 11130072
references.citation: New Phytol. 1992 Jul;121(3):347-375
references.pmid: 33874151
references.citation: Curr Opin Plant Biol. 2003 Apr;6(2):113-20
references.pmid: 12667866
references.citation: Funct Plant Biol. 2002 Jun;29(6):663-668
references.pmid: 32689512
references.citation: Eur J Biochem. 1992 Mar 1;204(2):821-30
references.pmid: 1311681
references.citation: Cell. 2000 Apr 28;101(3):331-40
references.pmid: 10847687
references.citation: EMBO J. 1991 Aug;10(8):2063-8
references.pmid: 2065654
references.citation: Annu Rev Plant Physiol Plant Mol Biol. 2001 Jun;52:139-162
references.pmid: 11337395
references.citation: Science. 2000 Aug 4;289(5480):768-71
references.pmid: 10926537
references.citation: Cell. 2000 Apr 28;101(3):319-29
references.pmid: 10847686
references.citation: Nucleic Acids Res. 1997 Sep 1;25(17):3389-402
references.pmid: 9254694
references.citation: EMBO J. 1999 Sep 1;18(17):4679-88
references.pmid: 10469647
references.citation: Plant Cell. 2001 Jun;13(6):1293-304
references.pmid: 11402161
references.citation: Science. 1999 Sep 3;285(5433):1579-82
references.pmid: 10477524
references.citation: Plant J. 2004 Oct;40(2):291-301
references.pmid: 15447654
references.citation: Plant Cell. 2001 Jun;13(6):1281-92
references.pmid: 11402160
references.citation: Proc Natl Acad Sci U S A. 1997 Aug 5;94(16):8515-20
references.pmid: 9238008
references.citation: Proc Natl Acad Sci U S A. 2004 Mar 2;101(9):3292-7
references.pmid: 14978263
references.citation: Mol Biol Evol. 1987 Jul;4(4):406-25
references.pmid: 3447015
references.citation: Plant Physiol. 2000 Aug;123(4):1471-82
references.pmid: 10938363
references.citation: Planta. 2000 Nov;211(6):761-9
references.pmid: 11144260
references.citation: Plant Mol Biol. 2003 Jul;52(5):981-97
references.pmid: 14558659
references.citation: Proc Natl Acad Sci U S A. 2003 Apr 15;100(8):4933-8
references.pmid: 12665620
references.citation: Plant J. 1999 Nov;20(3):333-42
references.pmid: 10571893
references.citation: Plant Physiol. 2003 Jun;132(2):732-8
references.pmid: 12805602
references.citation: Nature. 2003 Dec 4;426(6966):567-70
references.pmid: 14654842
references.citation: Plant Cell. 1997 Apr;9(4):491-507
references.pmid: 9144958
references.citation: Planta. 2003 Mar;216(5):789-97
references.pmid: 12624766
references.citation: Gene. 2004 Oct 27;341:83-92
references.pmid: 15474291
references.citation: Science. 2001 Aug 3;293(5531):880-3
references.pmid: 11486091
references.citation: Planta. 2004 Aug;219(4):705-13
references.pmid: 15127301
references.citation: Cell. 1998 Jun 26;93(7):1207-17
references.pmid: 9657153
references.citation: Plant Physiol. 2003 Dec;133(4):1530-8
references.pmid: 14605220
references.citation: Nature. 2002 Sep 5;419(6902):74-7
references.pmid: 12214234
references.citation: Plant Physiol. 2003 Dec;133(4):2021-8
references.pmid: 14630963
references.citation: Nature. 2003 Nov 20;426(6964):302-6
references.pmid: 14628054
references.citation: Development. 1998 Feb;125(3):485-94
references.pmid: 9425143
references.citation: Plant Physiol. 1999 Nov;121(3):889-896
references.pmid: 10557237
references.citation: Plant Cell. 2001 Dec;13(12):2659-70
references.pmid: 11752379