Skip to main content
Log in

Leafy cotyledon genes are essential for induction of somatic embryogenesis of Arabidopsis

  • Original Article
  • Published:
Planta Aims and scope Submit manuscript

Abstract

The capacity for somatic embryogenesis was studied in lec1, lec2 and fus3 mutants of Arabidopsis thaliana (L.) Heynh. It was found that contrary to the response of wild-type cultures, which produced somatic embryos via an efficient, direct process (65–94% of responding explants), lec mutants were strongly impaired in their embryogenic response. Cultures of the mutants formed somatic embryos at a low frequency, ranging from 0.0 to 3.9%. Moreover, somatic embryos were formed from callus tissue through an indirect route in the lec mutants. Total repression of embryogenic potential was observed in double (lec1 lec2, lec1 fus3, lec2 fus3) and triple (fus3 lec1 lec2) mutants. Additionally, mutants were found to exhibit efficient shoot regenerability via organogenesis from root explants. These results provide evidence that, besides their key role in controlling many different aspects of Arabidopsis zygotic embryogenesis, LEC/FUS genes are also essential for in vitro somatic embryogenesis induction. Furthermore, temporal and spatial patterns of auxin distribution during somatic embryogenesis induction were analyzed using transgenic Arabidopsis plants expressing GUS driven by the DR5 promoter. Analysis of data indicated auxin accumulation was rapid in all tissues of the explants of both wild type and the lec2-1 mutant, cultured on somatic embryogenesis induction medium containing 2,4-D. This observation suggests that loss of embryogenic potential in the lec2 mutant in vitro is not related to the distribution of exogenously applied auxin and LEC genes likely function downstream in auxin-induced somatic embryogenesis.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7

Similar content being viewed by others

Abbreviations

2,4-D:

2,4-Dichlorophenoxyacetic acid

ES:

Early stage

IAA:

Indole-3-acetic acid

IZE:

Immature zygotic embryo

LS:

Late stage

MZE:

Mature zygotic embryo

NAA:

1-Naphthaleneacetic acid

SAM:

Shoot apical meristem

WT:

Wild type

References

  • Aloni R, Schwalm K, Langhans M, Ulrich CI (2003) Gradual shifts in sites of free-auxin production during leaf-primordium development and their role in vascular differentiation and leaf morphogenesis in Arabidopsis. Planta 216:841–853

    PubMed  CAS  Google Scholar 

  • Berleth T (1998) Experimental approaches to Arabidopsis embryogenesis. Plant Physiol Biochem 36:69–82

    Article  CAS  Google Scholar 

  • Chugh A, Khurana PJ (2002) Gene expression during somatic embryogensis—recent advances. Curr Science 83:715–730

    CAS  Google Scholar 

  • Conway LJ, Poethig RS (1997) Mutations of Arabidopsis thaliana that transform leaves into cotyledons. Proc Natl Acad Sci USA 94:10209–10214

    Article  PubMed  CAS  Google Scholar 

  • Curaba J, Moritz T, Blervaque R, Parcy F, Raz V, Herzog M, Vachon G (2004) AtGA3ox2, a key gene responsible for bioactive gibberellin biosynthesis, is regulated during embryogenesis by LEAFY COTYLEDONS2 and FUS3 in Arabidopsis. Plant Physiol 136:3660–3669

    Article  PubMed  CAS  Google Scholar 

  • Feher A, Pasternak TP, Dudits D (2003) Transition of somatic plant cells to an embryogenic state. Plant Cell Tissue Org Cult 74:201–228

    Article  CAS  Google Scholar 

  • Feldmann KA, Marks MD (1986) Rapid and efficient regeneration of plants from explants of Arabidopsis thaliana. Plant Sci 47:63–69

    Article  Google Scholar 

  • Gaj MD (2001) Direct somatic embryogenesis as a rapid and efficient system for in vitro regeneration of Arabidopsis thaliana (L.) Heynh. Plant Cell Tis Org Cul 64:39–46

    Article  Google Scholar 

  • Gaj MD (2002) Stimulation of somatic embryo formation by mutagens and darkness in culture of immature zygotic embryos of Arabidopsis thaliana (L.) Heynh. Plant Growth Regul 37:93–98

    Article  CAS  Google Scholar 

  • Gaj MD (2004) Factors influencing somatic embryogenesis induction and plant regeneration with particular reference to Arabidopsis thaliana (L.) Heynh. Plant Growth Regul 43:27–47

    Article  CAS  Google Scholar 

  • Gamborg OL, Miller RA, Ojima K (1968) Nutrient requirement of suspension cultures of soybean root cells. Exp Cell Res 50:151–158

    Article  PubMed  CAS  Google Scholar 

  • Gazzarrini S, McCourt P (2003) Cross-talk in plant hormone signalling: what Arabidopsis mutants are telling us. Ann Bot 91:605–612

    Article  PubMed  CAS  Google Scholar 

  • Harada JJ (1999) Signalling in plant embryogenesis. Curr Opin Plant Biol 2:23–27

    Article  PubMed  CAS  Google Scholar 

  • Harada JJ (2001) Role of Arabidopsis LEAFY COTYLEDON genes in seed development. J Plant Physiol 158:405–409

    Article  CAS  Google Scholar 

  • Harada JJ, Stone SL, Kwong RW, Lee H, Kwong LW, Pelletier J (2003) Leafy cotyledon genes and the control of embryo development. In: Vasil IK (ed) Plant biotechnology 2002 and beyond. Kluwer, The Netherlands, pp 263–268

    Google Scholar 

  • Ikeda-Iwai M, Satoh S, Kamada H (2002) Establishment of reproducible tissue culture system for the induction of Arabidopsis somatic embryos. J Exp Bot 53:1575–1580

    Article  PubMed  CAS  Google Scholar 

  • Ikeda-Iwai M, Umehara M, Satoh S, Kamada H (2003) Stress-induced somatic embryogenesis in vegetative tissues of Arabidopsis thaliana. Plant J 34:107

    Article  PubMed  CAS  Google Scholar 

  • Jefferson RA, Kavanagh TA, Bevan MW (1987) GUS fusions: β-glucuronidase as a sensitive and versatile gene fusion marker in higher plants. EMBO J 6:3901–3907

    PubMed  CAS  Google Scholar 

  • Kroj T, Savino G, Valon C, Giraudat J, Parcy F (2003) Regulation of storage protein gene expression in Arabidopsis. Development 130:6065–6073

    Article  PubMed  CAS  Google Scholar 

  • Kwong RW, Bui AQ, Kwong LW, Fischer RL, Goldberg RW, Harada JJ (2003) LEAFY COTYLEDON-LIKE defines a class of a regulators essential for embryo development. Plant Cell 15:5–18

    Article  PubMed  CAS  Google Scholar 

  • Lee H, Fischer RL, Goldberg RB, Harada JJ (2003) Arabidopsis LEAFY COTYLEDON1 presents functionally specialized subunit of the CCAAT binding transcription factor. Proc Natl Acad Sci USA 100:2152–2156

    Article  PubMed  CAS  Google Scholar 

  • Lotan T, Ohto M, Yee KM, West MAL, Lo R, Kwong RW, Tamagishi K, Fisher RL, Goldberg RB, Harada JJ (1998) Arabidopsis LEAFY COTYLEDON1 is sufficient to induce embryo development in vegetative cells. Cell 93:1195–1205

    Article  PubMed  CAS  Google Scholar 

  • Luerssen H, Kirik V, Herrman P, Misera S (1998) FUSCA3 encodes a protein with a conserved Vp1/AB13-like B3 domain which is of functional importance for the regulation of seed maturation in Arabidopsis thaliana. Plant J 15:755–764

    Article  PubMed  CAS  Google Scholar 

  • Luo Y, Koop HS (1997) Somatic embryogenesis in cultured immature zygotic embryos and leaf protoplasts of Arabidopsis thaliana ecotypes. Planta 202:387–396

    Article  PubMed  CAS  Google Scholar 

  • Meinke D (1992) A homeotic mutant of Arabidopsis thaliana with leafy cotyledons. Science 258:1647–1650

    Article  PubMed  Google Scholar 

  • Meinke DW, Franzmann LH, Nickle TC, Yeung EC (1994) Leafy cotyledon mutants of Arabidopsis. Plant Cell 6:1049–1064

    Article  PubMed  CAS  Google Scholar 

  • Mordhorst AP, Hartog MV, El Talmer MK, Laux T, de Vries SC (2002) Somatic embryogenesis from Arabidopsis shoot apical meristem mutants. Planta 214:829–836

    Article  PubMed  CAS  Google Scholar 

  • Mordhorst AP, Toonen MAJ, de Vries SC (1997) Plant embryogenesis. Critical Rev Plant Sci 16:535–576

    Article  Google Scholar 

  • Mordhorst AP, Voerman KJ, Hartog MV, Meijer EA, VanWent J, Koornneef M, deVries SC (1998) Somatic embryogenesis in Arabidopsis thaliana is facilitated by mutation in genes repressing meristematic cell divisions. Genetics 149:549–563

    PubMed  CAS  Google Scholar 

  • Murashige T, Skoog FA (1962) A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol Plant 15:437–497

    Article  Google Scholar 

  • Ni DA, Wang LJ, Ding CH, Xu ZH (2001) Auxin distribution and transport during embryogenesis and seed germination of Arabidopsis. Cell Res 11:273–278

    Article  PubMed  CAS  Google Scholar 

  • Pasternak TP, Prinsen E, Ayaydin F, Miskolczi P, Potters G, Asard H, Van Onckelen HA, Dudits D, Feher A (2002) The role of auxins, pH, and stress in the activation of embryogenic cell division in leaf protoplast-derived cells of alfalfa. Plant Physiol 129:1807–1819

    Article  PubMed  CAS  Google Scholar 

  • Reidt W, Wohlfarth T, Ellestrom M, Czihal A, Tewes A, Ezcurra I, Rask L, Baumlein H (2000) Gene regulation during late embryogenesis: the RY motif of maturation-specific gene promoters is direct target of the FUS3 gene product. Plant J 21:401–408

    Article  PubMed  CAS  Google Scholar 

  • Reinert J (1958) Morphogenese und ihre Kontrolle an Gewebekulturen aus Carotten. Naturwissenschaften 45:344–345

    Article  CAS  Google Scholar 

  • Rider SD Jr, Henderson JT, Jerome RE, Edenberg HJ, Romero-Severson J, Ogas J (2003) Coordinate repression of regulators of embryogenic identity by PICKLE during germination in Arabidopsis. Plant J 35:33–43

    Article  PubMed  CAS  Google Scholar 

  • Sabatini S, Beis D, Wolkenfelt H, Maufett J, Guilfoyle T, Malamy J, Benfey P, Leyser O, Bechtold N, Weisbeek P, Scheres B (1999) An auxin-dependent distal organizer of pattern and polarity in the Arabidopsis root. Cell 99:463–472

    Article  PubMed  CAS  Google Scholar 

  • Souter M, Lindsey K (2000) Polarity and signalling in plant embryogenesis. J Exp Bot 51:971–983

    Article  PubMed  CAS  Google Scholar 

  • Steward FC, Mapes MO, Mears K (1958) Growth and organised development of cultured cells. I. Growth and division of freely suspended cells. Am J Bot 45:693–703

    Article  Google Scholar 

  • Stone SL, Kwong LW, Yee KM, Pelletier J, Lepiniec L, Fischer RL, Goldberg RB, Harada JJ (2001) LEAFY COTYLEDON2 encodes a B3 domain transcription factor that induces embryo development. Proc Natl Acad Sci USA 98:11806–11811

    Article  PubMed  CAS  Google Scholar 

  • Tsuchiya Y, Nambra E, Naito S, McCourt P (2004) The FUS3 transcription factor functions through the epidermal regulator TTG1 during embryogenesis in Arabidopsis. Plant J 37:73–81

    Article  PubMed  CAS  Google Scholar 

  • Ulmasov T, Murfett J, Hagen G, Gulifoyle TJ (1997) Aux/IAA proteins repress expression of reporter genes containing natural and highly active synthetic auxin response elements. Plant Cell 9:1963–1971

    Article  PubMed  CAS  Google Scholar 

  • von Recklinghausen IR, Iwanowska A, Kieft H, Mordhorst AP, Schel JHN, von Lammeren AAM (2000) Structure and development of somatic embryos formed in Arabidopsis pt mutant callus cultures derived from seedlings. Protoplasma 211:217–224

    Article  Google Scholar 

  • West MAL, Matsudaira YK, Danao J, Zimmerman JL, Fischer RL, Goldberg RB Harada JJ (1994) LEAFY COTYLEDON1 is an essential regulator of late embryogenesis and cotyledon identity in Arabidopsis. Plant Cell 6:1731–1745

    Article  PubMed  CAS  Google Scholar 

  • Wu Y, Haberland G, Zhou C, Koop H-U (1992) Somatic embryogenesis, formation of morphogenic callus and normal development in zygotic embryos of Arabidopsis thaliana in vitro. Protoplasma 169:89–96

    Article  Google Scholar 

  • Yazawa K, Takahata K, Kamada H (2004) Isolation of the gene encoding carrot leafy cotyledon1 and expression analysis during somatic and zygotic embryogenesis. Plant Physiol Biochem 42:215–223

    Article  PubMed  CAS  Google Scholar 

  • Zhang S, Wong L, Meng L, Lemaux PG (2002) Similarity of expression patterns of knotted 1 and ZmLEC1 during somatic and zygotic embryogenesis in maize (Zea mays L.). Planta 215:191–194

    Article  PubMed  CAS  Google Scholar 

  • Zimmerman L (1993) Somatic embryogenesis: a model for early development in higher plants. Plant Cell 5:1411–1423

    Article  PubMed  Google Scholar 

Download references

Acknowledgements

Malgorzata D. Gaj was supported by a Fulbright fellowship. We thank Jennifer Lynn Stonaker (Department of Plant and Microbial Biology, University of California, Berkeley) for help with the establishment of embryogenic cultures, Ling Meng (Department of Plant and Microbial Biology, University of California, Berkeley) for assistance in RT-PCR experiments, Julie Pelletier (Section of Plant Biology, Division of Biological Sciences, University of California, Davis) for maintenance of lec mutants and providing the lec2-1 mutant carrying DR5::GUS construct and Kelly Yee (Section of Plant Biology, Division of Biological Sciences, University of California, Davis) for construction of the double and triple mutants.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Malgorzata D. Gaj.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Gaj, M.D., Zhang, S., Harada, J.J. et al. Leafy cotyledon genes are essential for induction of somatic embryogenesis of Arabidopsis . Planta 222, 977–988 (2005). https://doi.org/10.1007/s00425-005-0041-y

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00425-005-0041-y

Keywords

Navigation