Plant Molecular Biology

, Volume 65, Issue 5, pp 677–692 | Cite as

Analysis of expression profile of selected genes expressed during auxin-induced somatic embryogenesis in leaf base system of wheat (Triticum aestivum) and their possible interactions

  • Bhumica Singla
  • Akhilesh K. Tyagi
  • Jitendra P. Khurana
  • Paramjit Khurana


Somatic embryogenesis is a notable illustration of plant totipotency and involves reprogramming of development in somatic cells toward the embryogenic pathway. Auxins are key components as their exogenous application recuperates the embryogenic potential of the mitotically quiescent somatic cells. In order to unravel the molecular basis of somatic embryogenesis, cDNA library was made from the regeneration proficient wheat leaf base segments treated with auxin. In total, 1440 clones were sequenced and among these 1,196 good quality sequences were assembled into 270 contigs and 425 were singletons. By reverse northern analysis, a total of 57 clones were found to be upregulated during somatic embryogenesis, 64 during 2,4-D treatment, and 170 were common to 2,4-D treatment and somatic embryogenesis. A substantial number of genes involved in hormone response, signal transduction cascades, defense, anti-oxidation, programmed cell death/senescence and cell division were identified and characterized partially. Analysis of data of select genes suggests that the induction phase of somatic embryogenesis is accompanied by the expression of genes that may also be involved in zygotic embryogenesis. The developmental reprogramming process may in fact involve multiple cellular pathways and unfolding of as yet unknown molecular events. Thus, an interaction network draft using bioinformatics and system biology strategy was constructed. The outcome of a systematic and comprehensive analysis of somatic embryogenesis associated interactome in a monocot leaf base system is presented.


Auxin Somatic embryogenesis Wheat 



We are grateful to Dr V Ravi for helping with the sequencing of the genes and assembly and thank Ms Rashmi Jain for helping with the in silico analysis. BS acknowledges the award of Senior Research Fellowship from the University Grants Commission (UGC), New Delhi. This research work was financially supported by the Department of Biotechnology, Government of India, and the UGC.

Supplementary material

11103_2007_9234_MOESM1_ESM.ppt (650 kb)
Magnified version of the rare cold inducible protein, which is the second major regulator in the molecular network (PPT 650 KB)
11103_2007_9234_MOESM2_ESM.ppt (800 kb)
Magnified version of the cytochrome P450, which is the third major regulator in the molecular network (PPT 802 KB)
11103_2007_9234_MOESM3_ESM.xls (49 kb)
The annotated ESTs for the 270 contigs (XLS 49 KB)
11103_2007_9234_MOESM4_ESM.xls (86 kb)
The annotated ESTs of 425 singletons (XLS 85 KB)
11103_2007_9234_MOESM5_ESM.xls (147 kb)
Proteins encoded by differentially expressed genes and their expression profile under three experimental conditions shown in Fig. 1, namely, control (A), 2,4-D 24 h (B) and SE (C). Color mark shows expression in a particular stage (XLS 147 KB)
11103_2007_9234_MOESM6_ESM.xls (22 kb)
List of the down-regulated ESTs (XLS 21 KB)
11103_2007_9234_MOESM7_ESM.xls (202 kb)
Some representative genes in the putative molecular interaction network draft during somatic embryogenesis in the wheat leaf base system (XLS 202 KB)
11103_2007_9234_MOESM8_ESM.xls (26 kb)
Some representative nodes in the putative molecular network draft during SE in wheat leaf base system (XLS 26 KB)
11103_2007_9234_MOESM9_ESM.xls (16 kb)
Some representative nodes in the glutathione-S-transferase pathway (XLS 16 KB)


  1. Altschul SF, Madden TL, Schaffer AA, Zhang J, Zhang Z, Miller W, Lipman DJ (1997) Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. Nucleic Acids Res 25:3389–3402CrossRefPubMedGoogle Scholar
  2. Anil VS, Rao KS (2000) Calcium-mediated signaling during sandalwood somatic embryogenesis. Role for exogenous calcium as second messenger. Plant Physiol 123:1301–1311CrossRefPubMedGoogle Scholar
  3. Anil VS, Harmon AC, Rao KS (2000) Spatio-temporal accumulation and activity of calcium-dependent protein kinases during embryogenesis, seed development, and germination in sandalwood. Plant Physiol 122:1035–1043CrossRefPubMedGoogle Scholar
  4. Ben C, Hewezi T, Jardinaud MF, Bena F, Ladouce N, Moretti S, Tamborindeguy C, Liboz T, Petitprez M, Gentzbittel L (2005) Comparative analysis of early embryonic sunflower cDNA libraries. Plant Mol Biol 57:255–270CrossRefPubMedGoogle Scholar
  5. Boutilier K, Offringa R, Sharma VK, Kieft H, Ouellet T, Zhang L, Hattori J, Liu CM, van Lammeren AA, Miki BL, Custers JB, van Lookeren Campagne MM (2002) Ectopic expression of BABY BOOM triggers a conversion from vegetative to embryonic growth. Plant Cell 14:1737–1749CrossRefPubMedGoogle Scholar
  6. Braybrook SA, Stone SL, Park S, Bui AQ, Brandon HL, Fischer R, Goldberg RB, Harada JJ (2006) Genes directly regulated by LEAFY COTYLEDON2 provide insight into the control of embryo maturation and somatic embryogenesis. Pro Natl Acad Sci USA 103:3468–3473CrossRefGoogle Scholar
  7. Che P, Love TM, Frame BR, Wang K, Carriquiry AL, Howell SH (2006) Gene expression patterns during somatic embryo development and germination in maize Hi II callus cultures. Plant Mol Biol 62:1–14CrossRefPubMedGoogle Scholar
  8. Chen JG, Ullah H, Young JC, Sussman MR, Jones AM (2001) ABP1 is required for organized cell elongation and division in Arabidopsis embryogenesis. Genes Dev 15:902–911CrossRefPubMedGoogle Scholar
  9. Chugh A, Khurana P (2002) Gene expression during somatic embryogenesis-recent advances. Curr Sci 83:715–730Google Scholar
  10. Davletova S, Meszaros T, Miskolczi P, Oberschall A, Torok K, Magyar Z, Dudits D, Deak M (2001) Auxin and heat shock activation of a novel member of the calmodulin like domain protein kinase gene family in cultured alfalfa cells. J Exp Bot 52:215–221CrossRefPubMedGoogle Scholar
  11. Dudits D, Bogre L, Gyorgyey J (1991) Molecular and cellular approaches to the analysis of plant embryo development from somatic cells in vitro. J Cell Sci 99:475–484Google Scholar
  12. Dudits D, Gyorgyey J, Bogre L, Bako L (1995) Molecular biology of somatic embryogenesis. In: Thorpe TA (ed) In vitro embryogenesis in plants. Kluwer Academic publishers, Dordrecht, pp 267–308Google Scholar
  13. Du L, Chen Z (2000) Identification of genes encoding receptor-like protein kinases as possible targets of pathogen- and salicylic acid-induced WRKY DNA-binding proteins in Arabidopsis. Plant J 24:837–47CrossRefPubMedGoogle Scholar
  14. Du L, Poovaiah BW (2005) Ca2+/ calmodulin is critical for brassinosteroid biosynthesis and plant growth. Nature 437:741–745CrossRefPubMedGoogle Scholar
  15. Edwards R, Dixon DP, Walbot V (2000) Plant glutathione S-transferases: enzymes with multiple functions in sickness and in health. Trends Plant Sci 5:193–198CrossRefPubMedGoogle Scholar
  16. Ewing B, Green P (1998) Base-calling of automated sequencer traces using phred. II. Error probabilities. Genome Res 8:186–194PubMedGoogle Scholar
  17. Ewing B, Hiller L, Wendl MC, Green P (1998) Base-calling of automated sequencer traces using phred. I. Accuracy assessment. Genome Res 8:175–185PubMedGoogle Scholar
  18. Fambrini M, Durante C, Cionini G, Geri C, Giorgetti L, Michelotti V, Salvini M, Pugliesi C (2006) Characterization of LEAFY COTYLEDON1-LIKE gene in Helianthus annuus and its relationship with zygotic and somatic embryogenesis. Dev Genes Evol 216:253–264CrossRefPubMedGoogle Scholar
  19. Feher A, Pasternak TP, Dudits D (2003) Transition of somatic cells to an embryogenic state. Plant Cell Tiss Org Cult 74:201–228CrossRefGoogle Scholar
  20. Gaj MD, Zhang S, Harada JJ, Lemaux PG (2005) Leafy cotyledon genes are essential for induction of somatic embryogenesis of Arabidopsis. Planta 222:977–988CrossRefPubMedGoogle Scholar
  21. Galland R, Randoux B, Vasseur J, Hilbert JL (2001) A glutathione S-transferase cDNA identified by mRNA differential display is upregulated during somatic embryogenesis in Cichorium. Biochim Biophys Acta 1522:212–216PubMedGoogle Scholar
  22. Giroux RW, Pauls KP (1997) Characterization of somatic embryogenesis-related cDNAs from alfalfa (Medicago sativa L.). Plant Mol Biol 33:393–404CrossRefPubMedGoogle Scholar
  23. Gordon D, Abajian C, Green P (1998) Consed: a graphical tool for sequence finishing. Genome Res 8:195–202PubMedGoogle Scholar
  24. Guilfoyle TJ (1999) Auxin-regulated genes and promoters. In: Hooykaas PJJ, Hall MA, Libbenga KR (eds) Biochemistry and molecular biology of plant hormones, Elsevier, Amsterdam, The Netherlands, pp 423–459CrossRefGoogle Scholar
  25. Harada H, Kiyosue T, Kamada H, Kobayashi K (1990) Stress induced carrot somatic embryogenesis and their application to synthetic seeds. In: Sangwan RS, Sangwan-Norreel BS (eds) The impact of biotechnology in agriculture, Kluwer Academic Publishers, Dordrecht, pp 129–157Google Scholar
  26. Hecht V, Vielle-Calzada J-P, Hartog MV, Schimdt Ed DL, Boutilier K, Grossniklaus U, de Vries SC (2001) The Arabidopsis somatic embryogenesis receptor kinase 1 gene is expessed in developing ovules and embryos and enhances embryogenic competence in cultures. Plant Physiol 127:803–816CrossRefPubMedGoogle Scholar
  27. Ikeda M, Umehara M, Kamada H (2006) Embryogenesis-related genes; its expression and roles during somatic embryogenesis in carrot and Arabidopsis. Plant Biotech 23:153–161Google Scholar
  28. Imin N, De Jong F, Mathesius U, van Noorden G, Saeed NA, Wang XD, Rose RJ, Rolfe BG (2004) Proteome reference maps of Medicago truncatula embryogenic cell cultures generated from single protoplasts. Proteomics 4:1883–1896CrossRefPubMedGoogle Scholar
  29. Imin N, Nizamidin M, Daniher D, Nolan KE, Rose RJ, Rolfe BG (2005) Proteomic analysis of somatic embryogenesis in Medicago truncatula. Explant cultures grown under 6-benzylaminopurine and 1-naphthaleneacetic acid treatments. Plant Physiol 137:1250–1260CrossRefPubMedGoogle Scholar
  30. Jain M, Kaur N, Garg R, Thakur JK, Tyagi AK, Khurana JP (2006a) Structure and expression analysis of early auxin-responsive Aux/IAA gene family in rice (Oryza sativa). Funct Integr Genomics 6:47–59CrossRefPubMedGoogle Scholar
  31. Jain M, Kaur N, Tyagi AK, Khurana JP (2006b) The auxin-responsive GH3 gene family in rice (Oryza sativa). Funct Integr Genomics 6:36–46CrossRefPubMedGoogle Scholar
  32. Jain M, Tyagi AK, Khurana JP (2006c) Genome-wide analysis, evolutionary expansion, and expression of early auxin-responsive SAUR gene family in rice (Oryza sativa). Genomics 88:360–371CrossRefPubMedGoogle Scholar
  33. Jansen MAK, Booij H, Schel JHN, de Vries SC (1990) Calcium increases the yield of somatic embryos in carrot embryogenic suspension cultures. Plant Cell Rep 9:221–223CrossRefGoogle Scholar
  34. Joo S, Park KY, Kim WT (2004) Light differentially regulates the expression of two members of the auxin-induced 1-amino cyclopropane-1-carboxylate synthase gene family in mung bean (Vigna radiata L.) seedlings. Planta 218:976–988CrossRefPubMedGoogle Scholar
  35. Kwong RW, Bui AQ, Lee H, Kwong LW, Fischer RL, Goldberg RB, Harada JJ (2003) LEAFY COTYLEDON1-LIKE defines a class of regulators essential for embryo development. Plant Cell 15:5–18CrossRefPubMedGoogle Scholar
  36. Kamada H, Kobayashi K, Kiyosue T, Harada H (1989) Stress induced somatic embryogenesis in carrot and its application to synthetic seed production. In Vitro Cell Dev Biol 25:1163–1166CrossRefGoogle Scholar
  37. Kamada H, Ishikawa K, Saga H, Harada H (1993) Induction of somatic embryogenesis in carrot by osmotic stress. Plant Tissue Cult Lett 10:38–44Google Scholar
  38. Kamada H, Tachikawa Y, Saitou T, Harada H (1994) Heat stress induction of carrot somatic embryogenesis. Plant Tissue Cult Lett 11:229–232Google Scholar
  39. Kikuchi A, Sanuki N, Higashi K, Koshiba T, Kamada H (2005) Abscisic acid and stress treatment are essential for the acquisition of embryogenic competence by carrot somatic cells. Planta 223:637–645CrossRefPubMedGoogle Scholar
  40. Kiyosue T, Kamada H, Harada H (1989a) Induction of somatic embryogenesis from carrot seeds by hypochlorite treatment. Plant Tissue Cult Lett 6:138–143Google Scholar
  41. Kiyosue T, Kamada H, Harada H (1989b) Induction of somatic embryogenesis by salt stress in carrot. Plant Tissue Cult Lett 6:162–164Google Scholar
  42. Kiyosue T, Takano K, Kamada H, Harada H (1990) Induction of somatic embryogenesis in carrot by heavy metal ions. Can J Bot 68:2021–2033CrossRefGoogle Scholar
  43. Lecourieux D, Ranjeva R, Pugin A (2006) Calcium in plant defence-signalling pathways. New Phytol 171:249–269CrossRefPubMedGoogle Scholar
  44. Levine A, Tenhaken R, Dixon R, Lamb C (1994) H2O2 from the oxidative burst orchestrates the plant hypersensitive disease resistance response. Cell 79:583–593CrossRefPubMedGoogle Scholar
  45. Li HC, Chuang K, Henderson JT, Rider SD Jr., Bai Y, Zhang H, Fountain M, Gerber J, Ogas J (2005) PICKLE acts during germination to repress expression of embryonic traits. Plant J 44:1010–1022CrossRefPubMedGoogle Scholar
  46. Li J, Nam KH (2002) Regulation of brassinosteroid signaling by a GSK3/SHAGGY-like kinase. Science 295:1299–1301PubMedGoogle Scholar
  47. Li S, Xing GM, Cui KR, Yu CH, Zhang X, Xu HX, Wang YF (2003) Ultracytochemical localization of calcium and ATPase activity on the 2,4-D induced somatic embryogenesis of Lycium barbarum L. Shi Yan Sheng Wu Xue Bao 36:414–420PubMedGoogle Scholar
  48. Lin X, Hwang GJ, Zimmerman JL (1996) Isolation and characterization of a diverse set of genes from carrot somatic embryos. Plant Physiol 112:1365–1374CrossRefPubMedGoogle Scholar
  49. Mahalakshmi A, Khurana JP, Khurana P (2003) Rapid induction of somatic embryogenesis by 2,4-D in leaf base cultures of wheat (Triticum aestivum L.). Plant Biotech 20:267–273Google Scholar
  50. Mahalakshmi A, Singla B, Khurana JP, Khurana P (2007) Role of calcium-calmodulin in auxin-induced somatic embryogenesis in leaf base cultures of wheat (Triticum aestivum var. HD 2329). Plant Cell Tiss Org Cult 88: 167–174CrossRefGoogle Scholar
  51. Marrs KA (1996) The function and regulation of glutathione-S-transferases in plants. Annu Rev Plant Physiol Plant Mol Biol 47:127–158CrossRefPubMedGoogle Scholar
  52. Maraschin SF, Priester W, Spaink HP, Wang M (2005) Androgenetic switch an example of plant embryogenesis from the male gametophyte perspective. J Exp Bot 56:1711–1726CrossRefPubMedGoogle Scholar
  53. Michalczuk L, Cooke TJ, Cohen JD (1992a) Auxin levels at different stages of carrot somatic embryogenesis. Phytochemistry 31:1097–1103CrossRefGoogle Scholar
  54. Michalczuk L, Ribnicky DM, Cooke TJ, Cohen JD (1992b) Regulation of indole-3-acetic acid biosynthetic pathways in carrot cell cultures. Plant Physiol 100:1346–1353CrossRefPubMedGoogle Scholar
  55. Mordhost AP, Toonen MAJ, de Vries SC (1997) Plant embryogenesis. Crit Rev Plant Sci 16:535–576Google Scholar
  56. Nagata T, Ishida S, Hasezawa S, Takahashi Y (1994) Genes involved in the dedifferentiation of plant cells. Int J Dev Biol 38:321–327PubMedGoogle Scholar
  57. Nakamura A, Nakajima N, Goda H, Shimada Y, Hayashi K, Nozaki H, Asami T, Yoshida S, Fujioka S (2006) Arabidopsis Aux/IAA genes are involved in brassinosteroid-mediated growth responses in a manner dependent on organ type. Plant J 45:193–205CrossRefPubMedGoogle Scholar
  58. Nishiwaki M, Fujino K, Koda Y, Masuda K, Kikuta Y (2000) Somatic embryogenesis induced by the simple application of abscisic acid to carrot (Daucus carota L.) seedlings in culture. Planta 211:756–759CrossRefPubMedGoogle Scholar
  59. Nolan KE, Irwanto RR, Rose RJ (2003) Auxin up-regulates MtSERK1 expression in both Medicago truncatula root-forming and embryogenic cultures. Plant Physiol 133:218–230CrossRefPubMedGoogle Scholar
  60. Nolan KE, Saeed NA, Rose RJ (2006) The stress kinase gene MtSK1 in Medicago truncatula with particular reference to somatic embryogenesis. Plant Cell Rep 25:711–722CrossRefPubMedGoogle Scholar
  61. Nomura K, Komamine A (1995) Physiologicl and biochemical aspects of somatic embryogenesis. In: Thorpe TA (ed) In vitro embryogenesis in plants, Kluwer Academic Publishers, Dordrecht, pp 249–266Google Scholar
  62. Ogas J, Cheng JC, Sung ZR, Somerville C (1997) Cellular differentiation regulated by gibberellin in the Arabidopsis thaliana pickle mutant. Science 277:91–94CrossRefPubMedGoogle Scholar
  63. Ogas J, Kaufmann S, Handerson J, Somerville C (1999) PICKLE is a CHD3 chromatin-remodeling factor that regulates the transition from embryonic to vegetative development in Arabidopsis. Proc Natl Acad Sci USA 96:13839–13844CrossRefPubMedGoogle Scholar
  64. Ogata Y, Iizuka M, Nakayama D, Ikeda M, Kamada H, Koshiba T (2005) Possible involvent of abscisic acid in the induction of secondary somatic embryogenesis on seed coat-derived carrot somatic embryos. Planta 221:417–423CrossRefPubMedGoogle Scholar
  65. Overvoorde PI, Grimes HD (1994) The role of calcium and calmodulin in carrot somatic embryo. Plant Cell Physiol 35:135–144Google Scholar
  66. Park JE, Park JY, Kim YS, Staswick PE, Jeon J, Yun J, Kim SY, Kim J, Lee YH, Park CM (2007) GH3-mediated auxin homeostasis links growth regulation with stress adaptation response in Arabidopsis. J Biol Chem 282:10036–10046CrossRefPubMedGoogle Scholar
  67. Pasternak TP, Prinsen E, Ayaydin F, Miskolczi P, Potters G, Asard H, Van Onckelen HA, Dudits D, Feher A (2002) The role of auxin, pH, and stress in the activation of embryogenic cell division in leaf protoplast-derived cells of alfalfa. Plant Physiol 129:1807–1819CrossRefPubMedGoogle Scholar
  68. Patnaik D, Khurana P (2005) Identification of a phosphoprotein expressed during somatic embryogenesis in wheat leaf base cultures. J Plant Biochem Biotech 14:149–154Google Scholar
  69. Pfeiffer W, Hoftberger M (2001) Oxidative burst in Chenopodium rubrum suspension cells: induction by auxin and osmotic changes. Plant Physiol 3:144–150Google Scholar
  70. Puigderrajols P, Jofre A, Mir G, Pla M, Verdaguer D, Huguet G, Molinas M (2002) Developmentally and stress-induced small heat shock proteins in cork oak somatic embryos. J Exp Bot 53:1445–1452CrossRefPubMedGoogle Scholar
  71. Quint M, Gary WM (2006) Auxin signaling. Curr Opin Plant Biol 9:448–453CrossRefPubMedGoogle Scholar
  72. Quiroz-Figueroa FR, Rojas-Herrera R, Galaz-Avalos RM, Loyola-Vargas VM (2006) Embryo production through somatic embryogenesis can be used to study cell differentiation in plants. Plant Cell Tiss Org Cult 86:285–301CrossRefGoogle Scholar
  73. Raghavan V (2006) Can carrot and Arabidopsis serve as model systems to study the molecular biology of somatic embryogenesis? Curr Sci 90:1336–1343Google Scholar
  74. Rani AR, Reddy VD, Prakash Babu P, Padmaja G (2005) Changes in protein profiles associated with somatic embryogenesis in peanut. Biol Plant 49:347–354CrossRefGoogle Scholar
  75. Rensing SA, Daniel L, Schumann, Reski R, Hohe A (2005) EST sequencing from embryogenic Cyclamen persicum cell cultures identifies a high proportion of transcripts homologous to plant genes involved in somatic embryogenesis. J Plant Growth Regu 24:102–115CrossRefGoogle Scholar
  76. Saito Y, Yamasaki S, Fujii N, Takahashi H (2005) Possible involvement of CS-ACS1 and ethylene in auxin-induced peg formation of cucumber seedlings. Ann Bot (Lond) 95:413–422CrossRefGoogle Scholar
  77. Sallandrouze A, Faurobert M, El Maataoui M, Espagnac H (1999) Two-dimensional electrophoretic analysis of proteins associated with somatic embyrogenesis in Cupressus sempervirens L. Electrophoresis 20:1109–1119CrossRefPubMedGoogle Scholar
  78. Santarem ER, Pelissier B, Finer JJ (1997) Effect of explant orientation, pH, solidifying agent and wounding on initiation of soybean somatic embryos. In Vitro Cell Dev Biol 33:13–19CrossRefGoogle Scholar
  79. Schmidt ED, Guzzo F, Toonen MA, de Vries SC (1997) A leucine-rich repeat containing receptor-like kinase marks somatic plant cells competent to form embryos. Development 124:2049–2062PubMedGoogle Scholar
  80. Singla B, Chugh A, Khurana JP, Khurana P (2006) An early auxin-responsive Aux/IAA gene from wheat (Triticum aestivum) is induced by epibrassinolide and differentially regulated by light and calcium. J Exp Bot 57:4059–4070CrossRefPubMedGoogle Scholar
  81. Srinivasan C, Liu Z, Heidmann I, Supena ED, Fukuoka H, Joosen R, Lambalk J, Angenent G, Scorza R, Custers JB, Boutilier K (2007) Heterologous expression of the BABY BOOM AP2/ERF transcription factor enhances the regeneration capacity of tobacco (Nicotiana tabacum L.). Planta 225:341–351CrossRefPubMedGoogle Scholar
  82. Stasolla C, Bozhkov PV, Chu TM, Van Zyl L, Egertsdotter U, Suarez MF, Craig D, Wolfinger RD, Von Arnold S, Sederoff RR (2004) Variation in transcript abundance during somatic embryogenesis in gymnosperms. Tree Physiol 24:1073–1085PubMedGoogle Scholar
  83. Stone SL, Kwong LW, Yee KM, Pelletier J, Lepiniec L, Fischer RL, Goldberg RB, Harada JJ (2001) LEAFY COTYLEDON2 encodes B3 domain transcription factor that induces embryo development. Proc Natl Acad Sci USA 98:11806–11811CrossRefPubMedGoogle Scholar
  84. Sung ZR, Okimoto R (1983) Coordinate gene expression during somatic embryogenesis in carrots. Proc Natl Acad Sci USA 80:2661–2665CrossRefPubMedGoogle Scholar
  85. Tahir M, Law DA, Stasolla C (2006) Molecular characterization of PgAGO, a novel conifer gene of the Argonaute family expressed in apical cells and required for somatic embryo development in spruce. Tree Physiol 26:1257–1270PubMedGoogle Scholar
  86. Thibaud-Nissen F, Shealy RT, Khanna A, Vodkin LO (2003) Clustering of microarray data reveals transcript patterns associated with somatic embryogenesis in soybean. Plant Physiol 132:118–136CrossRefPubMedGoogle Scholar
  87. Thomas C, Bronner R, Molinier J, Prinsen E, van Onckelen H, Hahne G (2002) Immuno-cytochemical localization of indole-3-acetic acid during induction of somatic embryogenesis in cultured sunflower embryos. Planta 215:577–583CrossRefPubMedGoogle Scholar
  88. Thomas C, Meyer D, Himber C, Steinmetz A (2004) Spatial expression of a sunflower SERK gene during induction of somatic embryogenesis and shoot organogenesis. Plant Physiol Biochem 42:35–42CrossRefPubMedGoogle Scholar
  89. Timmers ACJ, De Vries SC, Schel JHN (1989) Distribution of membrane-bound calcium and activated calmodulin during somatic embryogenesis of carrot (Daucus carota L.). Protoplasma 153:24–29CrossRefGoogle Scholar
  90. van der Kop DA, Schuyer M, Pinas JE, van der Zaal BJ, Hooykaas PJ (1999) Selection of Arabidopsis mutants overexpressing genes driven by the promoter of an auxin-inducible glutathione S-transferase gene. Plant Mol Biol 39:979–990CrossRefPubMedGoogle Scholar
  91. van der Kop DA, Schuyer M, Scheres B, van der Zaal BJ, Hooykaas PJ (1996) Isolation and characterization of an auxin-inducible glutathione S-transferase gene of Arabidopsis thaliana. Plant Mol Biol 30:839–844CrossRefPubMedGoogle Scholar
  92. Verdus M-C, Dubois T, Dubois J, Vasseur J (1993) Ultrastructural changes in leaves of Cichorium during somatic embryogenesis. Ann Bot 72:375–383CrossRefGoogle Scholar
  93. Winkelmann T, Heintz D, Van Dorsselaer A, Serek M, Braun HP (2006) Proteomic analyses of somatic and zygotic embryos of Cyclamen persicum Mill. reveal new insights into seed and germination physiology. Planta 224:508–519CrossRefPubMedGoogle Scholar
  94. Woodward AW, Bartel B. (2005) Auxin: regulation, action, and interaction. Ann Bot (Lond) 95:707–735CrossRefGoogle Scholar
  95. Zimmerman JL (1993) Somatic embryogenesis: a model for early development in higher plants. Plant Cell 5:1411–1423CrossRefPubMedGoogle Scholar
  96. Zeng F, Zhang X, Zhu L, Tu L, Guo X, Nie Y (2006) Isolation and characterization of genes associated to cotton somatic embryogenesis by suppression subtractive hybridization and macroarray. Plant Mol Biol 60:167–183CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Bhumica Singla
    • 1
  • Akhilesh K. Tyagi
    • 1
  • Jitendra P. Khurana
    • 1
  • Paramjit Khurana
    • 1
  1. 1.Interdisciplinary Centre for Plant Genomics & Department of Plant Molecular BiologyUniversity of Delhi South CampusNew DelhiIndia

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