Plant Molecular Biology

, Volume 73, Issue 1–2, pp 143–156 | Cite as

Alteration of PHYA expression change circadian rhythms and timing of bud set in Populus

  • Iwanka Kozarewa
  • Cristian Ibáñez
  • Mikael Johansson
  • Erling Ögren
  • David Mozley
  • Eva Nylander
  • Makiko Chono
  • Thomas Moritz
  • Maria E. Eriksson


In many temperate woody species, dormancy is induced by short photoperiods. Earlier studies have shown that the photoreceptor phytochrome A (phyA) promotes growth. Specifically, Populus plants that over-express the oat PHYA gene (oatPHYAox) show daylength-independent growth and do not become dormant. However, we show that oatPHYAox plants could be induced to set bud and become cold hardy by exposure to a shorter, non-24 h diurnal cycle that significantly alters the relative position between endogenous rhythms and perceived light/dark cycles. Furthermore, we describe studies in which the expression of endogenous Populus tremula × P. tremuloides PHYTOCHROME A (PttPHYA) was reduced in Populus trees by antisense inhibition. The antisense plants showed altered photoperiodic requirements, resulting in earlier growth cessation and bud formation in response to daylength shortening, an effect that was explained by an altered innate period that leads to phase changes of clock-associated genes such as PttCO2. Moreover, gene expression studies following far-red light pulses show a phyA-mediated repression of PttLHY1 and an induction of PttFKF1 and PttFT. We conclude that the level of PttPHYA expression strongly influences seasonally regulated growth in Populus and is central to co-ordination between internal clock-regulated rhythms and external light/dark cycles through its dual effect on the pace of clock rhythms and in light signaling.


Growth cessation Dormancy Circadian clock Photoperiodism Phytochrome Populus 



Cauliflower mosaic virus


Critical daylength


Constant light


Constant dark




Long day


Short day


Zeitgeber time



We are grateful to Ingabritt Carlsson, Gunilla Malmberg, Marie Nygren, Kjell Olofsson, Medisa Hasić, Isabella Pekkari and Sofia Österberg for their excellent technical assistance and to the Wallenberg greenhouse staff for their valuable help. Luis Muniz and Harriet G. McWatters are acknowledged for helpful scientific discussions. We thank Andrew J. Millar for the gift of the promoter:LUC constructs and BRASS software. We are also grateful for valuable help from Yury Shatz regarding the PixelSmart plug-in for ImageJ. This work was supported by grants to MEE from the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS), the Swedish Research Council (VR), the Knut and Alice Wallenberg Foundation and Nils och Dorthi Troëdssons forskningsfond. The research was also supported by the Swedish Natural Science Research Council (NFR), Swedish Research Council for Agricultural Sciences (SJFR), the Swedish Foundation for Strategic Research (SSF), the Kempe Foundation and a Human Frontier Science Program (RG0303) to TM.

Supplementary material

11103_2010_9619_MOESM1_ESM.doc (34 kb)
(DOC 33 kb)
11103_2010_9619_MOESM2_ESM.doc (32 kb)
(DOC 32 kb)
11103_2010_9619_MOESM3_ESM.doc (4.9 mb)
(DOC 5043 kb)
11103_2010_9619_MOESM4_ESM.doc (2 mb)
(DOC 2083 kb)
11103_2010_9619_MOESM5_ESM.doc (5.9 mb)
(DOC 6063 kb)
11103_2010_9619_MOESM6_ESM.doc (290 kb)
(DOC 290 kb)
11103_2010_9619_MOESM7_ESM.doc (78 kb)
(DOC 77 kb)


  1. Alabadí D, Oyama T, Yanovsky MJ, Harmon FG, Más P, Kay SA (2001) Reciprocal regulation between TOC1 and LHY/CCA1 within the Arabidopsis circadian clock. Science 293:880–883CrossRefPubMedGoogle Scholar
  2. Böhlenius H, Huang T, Charbonnel-Campaa L, Brunner AM, Jansson S, Strauss SH, Nilsson O (2006) CO/FT regulatory module controls timing of flowering and seasonal growth cessation in trees. Science 312:1040–1043CrossRefPubMedGoogle Scholar
  3. Bünning E (1936) Die endogene Tagesrhythmik als Grudlage der photoperiodischen Reaktion. Ber Deut Bot Ges 54:590–607Google Scholar
  4. Clack T, Mathews S, Sharrock RA (1994) The phytochrome apoprotein family in Arabidopsis is encoded by five genes: The sequences and expression of PHYD and PHYE. Plant Mol Biol 25:413–427CrossRefPubMedGoogle Scholar
  5. Corbesier L, Vincent C, Jang SH, Fornara F, Fan QZ, Searle I, Giakountis A, Farrona S, Gissot L, Turnbull C, Coupland G (2007) FT protein movement contributes to long-distance signaling in floral induction of Arabidopsis. Science 316:1030–1033CrossRefPubMedGoogle Scholar
  6. Czechowski T, Bari RP, Stitt M, Scheible WR, Udvardi MK (2004) Real-time RT-PCR profiling of over 1400 Arabidopsis transcription factors: unprecedented sensitivity reveals novel root- and shoot-specific genes. Plant J 38:366–379CrossRefPubMedGoogle Scholar
  7. Devlin PF (2002) Signs of the time: environmental input to the circadian clock. J Exp Bot 53:1535–1550CrossRefPubMedGoogle Scholar
  8. Dunlap JC (1999) Molecular bases for circadian clocks. Cell 96:271–290CrossRefPubMedGoogle Scholar
  9. Eriksson ME, Millar AJ (2003) The circadian clock: a plant’s best friend in a spinning world. Plant Physiol 13:732–738CrossRefGoogle Scholar
  10. Eriksson M, Moritz T (1997) Isolation of a cDNA encoding a phytochrome A (Accession No. AJ001318) from Populus tremula × tremuloides. Plant Gene Register # PGR97-186. Plant Physiol 115:1731Google Scholar
  11. Eriksson ME, Moritz T (2002) Daylength and spatial expression of a gibberellin 20-oxidase isolated from hybrid aspen (Populus tremula L. × P. tremuloides Michx.). Planta 214:920–930CrossRefPubMedGoogle Scholar
  12. Eriksson ME, Israelsson M, Olsson O, Moritz T (2000) Increased gibberellin biosynthesis in transgenic trees promotes growth, biomass production and xylem fiber length. Nat Biotechnol 18:784–788CrossRefPubMedGoogle Scholar
  13. Flint HL, Boyce BR, Beattie DJ (1967) Index of injury—a useful expression of freezing injury to plant tissues as determined by electrolytic method. Can J Plant Sci 47:229–230CrossRefGoogle Scholar
  14. Harmer SL, Hogenesch JB, Straume M, Chang H-S, Han B, Zhu T, Wang X, Kreps JA, Kay SA (2000) Orchestrated transcription of key pathways in Arabidopsis by the circadian clock. Science 290:2110–2113CrossRefPubMedGoogle Scholar
  15. Howe GT, Bucciagalia PA, Hackett WP, Furnier GR, Cordonnier-Pratt M-M, Gardner G (1998) Evidence that the phytochrome gene family in black cottonwood has one PHYA locus and two PHYB loci but lacks members of the PHYC/F and PHYE family. Mol Biol Evol 15:160–175PubMedGoogle Scholar
  16. Imaizumi T, Tran HG, Swartz T, Briggs WR, Kay SA (2003) FKF1 is essential for photoperiodic-specific light signaling in Arabidopsis. Nature 426:302–306CrossRefPubMedGoogle Scholar
  17. Imaizumi T, Schultz TF, Harmon FG, Ho LA, Kay SA (2005) FKF1 F-BOX protein mediates cyclic degradation of a repressor of CONSTANS in Arabidopsis. Science 309:293–297CrossRefPubMedGoogle Scholar
  18. Johnson E, Bradley M, Harberd NP, Whitelam GC (1994) Photoresponses of light-grown phyA mutants of Arabidopsis—phytochrome A is required for the perception of daylength extensions. Plant Physiol 105:141–149CrossRefPubMedGoogle Scholar
  19. Koncz C, Schell J (1986) The promoter of T L-DNA gene 5 controls the tissue-specific expression of chimaeric genes carried by a novel type of binary vector. Mol Gen Genet 204:383–396CrossRefGoogle Scholar
  20. Kreps JA, Simon AE (1997) Environmental and genetic effects on circadian clock-regulated gene expression in Arabidopsis. Plant Cell 9:297–304CrossRefPubMedGoogle Scholar
  21. Lin C, Ahmad M, Cashmore AR (1996) Arabidopsis cryptochrome 1 is a soluble protein mediating blue light-dependent regulation of plant growth and development. Plant J 10:893–902CrossRefPubMedGoogle Scholar
  22. Lin C, Yang H, Guo H, Mockler T, Chen J, Cashmore AR (1998) Enhancement of blue-light sensitivity of Arabidopsis seedlings by a blue light receptor cryptochrome 2. Proc Natl Acad Sci USA 95:2686–2690CrossRefPubMedGoogle Scholar
  23. Locke JC, Millar AJ, Turner MS (2005) Modelling genetic networks with noisy and varied experimental data: the circadian clock in Arabidopsis thaliana. J Theor Biol 234:383–393CrossRefPubMedGoogle Scholar
  24. McWatters HG, Bastow RM, Hall A, Millar AJ (2000) The ELF3 zeitnehmer regulates light signalling to the circadian clock. Nature 408:716–720CrossRefPubMedGoogle Scholar
  25. Millar AJ, Carré IA, Strayer CA, Chua N-H, Kay SA (1995) Circadian clock mutants in Arabidopsis identified by luciferase imaging. Science 267:1161–1163CrossRefPubMedGoogle Scholar
  26. Møhlmann JA, Asante DKA, Jensen JB, Krane MN, Ernstsen A, Junttila O, Olsen JE (2005) Low night temperature and inhibition of gibberellin biosynthesis override phytochrome action and induce bud set and cold acclimation, but not dormancy in PHYA overexpressors and wild-type of hybrid aspen. Plant Cell Environ 28:1579–1588CrossRefGoogle Scholar
  27. Olsen JE, Junttila O (2002) Far red end-of-day treatment restores wild type-like plant length in hybrid aspen overexpressing phytochrome A. Physiol Plant 115:448–457CrossRefPubMedGoogle Scholar
  28. Olsen JE, Junttila O, Moritz T (1995) A localised decrease of GA1 in shoot tips of Salix pentandra seedlings preceds cessation of shoot elongation under short photoperiod. Physiol Plant 95:627–632CrossRefGoogle Scholar
  29. Olsen JE, Junttila O, Nilsen J, Eriksson ME, Martinussen I, Olsson O, Sandberg G, Moritz T (1997) Ectopic expression of oat phytochrome A in hybrid aspen changes critical day length for growth and prevents cold acclimation. Plant J 12:1339–1350CrossRefGoogle Scholar
  30. Perales M, Más P (2007) A functional link between rhythmic changes in chromatin structure and the Arabidopsis biological clock. Plant Cell 19:2111–2123CrossRefPubMedGoogle Scholar
  31. Plautz JD, Straume M, Stanewsky R, Jamison CF, Brandes C, Dowse HB, Hall JC, Kay SA (1997) Quantitative analysis of Drosophila period gene transcription in living animals. J Biol Rhythms 12:204–217CrossRefPubMedGoogle Scholar
  32. Putterill J, Robson F, Lee K, Simon R, Coupland G (1995) The CONSTANS gene of Arabidopsis promotes flowering and encodes a protein showing similarities to Zinc-finger transcription factors. Cell 80:847–857CrossRefPubMedGoogle Scholar
  33. Ramírez-Carvajal GA, Morse AM, Davis JM (2008) Transcript profiles of the cytokinin response regulator gene family in Populus imply diverse roles in plant development. New Phytol 177:77–89PubMedGoogle Scholar
  34. Ramos A, Pérez-Solís E, Ibáñez C, Casado R, Collada C, Gómez L, Aragoncillo C, Allona I (2005) Winter disruption of the circadian clock in chestnut. Proc Natl Acad Sci USA 102:7037–7042CrossRefPubMedGoogle Scholar
  35. Roden LC, Song H-R, Jackson S, Morris K, Carre IA (2002) Floral responses to photoperiod are correlated with the timing of rhythmic expression relative to dawn and dusk in Arabidopsis. Proc Natl Acad Sci USA 99:13313–13318CrossRefPubMedGoogle Scholar
  36. Rohde A, Bhalerao RP (2007) Plant dormancy in the perennial context. Trends Plant Sci 12:217–223CrossRefPubMedGoogle Scholar
  37. Ruonala R, Rinne PLH, Kangasjärvi J, Schoot C (2008) CENL1 expression in the rib meristem affects stem elongation and the transition to dormancy in Populus. Plant Cell 20:59–74CrossRefPubMedGoogle Scholar
  38. Ruttink T, Arend M, Morreel K, Storme V, Rombauts S, Fromm J, Bhalerao RP, Boerjan W, Rohde A (2007) A molecular timetable for apical bud formation and dormancy induction in poplar. Plant Cell 19:2370–2390CrossRefPubMedGoogle Scholar
  39. Salazar JD, Saithong T, Brown PE, Foreman J, Locke JCW, Halliday KJ, Carré IA, Rand DA, Millar AJ (2009) Prediction of photoperiodic regulators from quantitative gene circuit models. Cell 139:1170–1179CrossRefPubMedGoogle Scholar
  40. Salome PA, McClung CR (2005) What makes the Arabidopsis clock tick on time? A review on entrainment. Plant Cell Environ 28:21–38CrossRefGoogle Scholar
  41. Samach A, Onouchi H, Gold SE, Ditta GS, Schwarz-Sommer Z, Yanofsky MF, Coupland G (2000) Distinct roles of CONSTANS target genes in reproductive development of Arabidopsis. Science 288:1613–1616CrossRefPubMedGoogle Scholar
  42. Sawa M, Nusinow DA, Kay SA, Imaizumi T (2007) FKF1 and GIGANTEA complex formation is required for day-length measurement in Arabidopsis. Science 318:261–265CrossRefPubMedGoogle Scholar
  43. Schaffer R, Ramsay N, Samach A, Corden S, Putterill J, Carre IA, Coupland G (1998) The late elongated hypocotyl mutation of Arabidopsis disrupts circadian rhythms and the photoperiodic control of flowering. Cell 93:1219–1229CrossRefPubMedGoogle Scholar
  44. Somers DE, Devlin PF, Kay SA (1998) Phytochromes and cryptochromes in the entrainment of the Arabidopsis circadian clock. Science 282:1482–1490CrossRefGoogle Scholar
  45. Strayer C, Oyama T, Schultz TF, Raman R, Somers DE, Más P, Panda S, Kreps JA, Kay SA (2000) Cloning of the Arabidopsis clock gene TOC1, an autoregulatory response regulator homolog. Science 289:768–771CrossRefPubMedGoogle Scholar
  46. Suárez-López P, Wheatley K, Robson F, Onouchi H, Valverde F, Coupland G (2001) CONSTANS mediates between the circadian clock and the control of flowering in Arabidopsis. Nature 410:1116–1120CrossRefPubMedGoogle Scholar
  47. Swarup K, Alonso-Blanco C, Lynn JR, Michaels SD, Amasino RM, Koorneef M, Millar AJ (1999) Natural allelic variation identifies new genes in the Arabidobsis circadian system. Plant J 20:67–77CrossRefPubMedGoogle Scholar
  48. Takata N, Saito S, Saito CT, Nanjo T, Shinohara K, Uemura M (2009) Molecular phylogeny and expression of poplar circadian clock genes, LHY1 and LHY2. New Phytol 181:808–819CrossRefGoogle Scholar
  49. Tepperman JM, Zhu T, Chang HS, Wang X, Quail PH (2001) Multiple transcription-factor genes are early targets of phytochrome A signaling. Proc Natl Acad Sci USA 98:9437–9442CrossRefPubMedGoogle Scholar
  50. Thomas B, Vince-Prue D (1997) Photoperiodism in plants, 2nd edn. Academic Press, LondonGoogle Scholar
  51. Valverde F, Mouradov A, Soppe W, Ravenscroft D, Samach A, Coupland G (2004) Photoreceptor regulation of CONSTANS protein in photoperiodic flowering. Science 303:1003–1006CrossRefPubMedGoogle Scholar
  52. Wang ZY, Tobin EM (1998) Constitutive expression of the CIRCADIAN CLOCK ASSOCIATED 1 (CCA1) gene disrupts circadian rhythms and suppresses its own expression. Cell 93:1207–1217CrossRefPubMedGoogle Scholar
  53. Wareing PF (1956) Photoperiodism in woody plants. Annu Rev Plant Physiol Plant Mol Biol 7:191–214Google Scholar
  54. Welling A, Moritz T, Palva ET, Junttila O (2002) Independent activation of cold acclimation by low temperature and short photoperiod in hybrid aspen. Plant Physiol 129:1633–1641CrossRefPubMedGoogle Scholar
  55. Yanovsky MJ, Kay SA (2002) Molecular basis of seasonal time measurement in Arabidopsis. Nature 419:308–312CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Iwanka Kozarewa
    • 1
    • 3
  • Cristian Ibáñez
    • 1
    • 4
  • Mikael Johansson
    • 1
  • Erling Ögren
    • 2
  • David Mozley
    • 2
  • Eva Nylander
    • 1
  • Makiko Chono
    • 2
    • 5
  • Thomas Moritz
    • 2
  • Maria E. Eriksson
    • 1
  1. 1.Department of Plant Physiology, Umeå Plant Science CentreUmeå UniversityUmeåSweden
  2. 2.Department of Forest Genetics and Plant Physiology, Umeå Plant Science CentreSwedish University of Agricultural SciencesUmeåSweden
  3. 3.Wellcome Trust Sanger InstituteHinxton, CambridgeshireUK
  4. 4.Facultad de Ciencias, Departamento de BiologíaUniversidad de La SerenaLa SerenaChile
  5. 5.Research Team for Wheat and Barley Biotechnology, National Institute of Crop ScienceNational Agriculture and Food Research OrganizationTsukubaJapan

Personalised recommendations