When microspores decide to become embryos — cellular and molecular changesThis review is one of a selection of papers published in the Special Issue on Plant Cell Biology.

Cultured microspores can be induced to develop into fully functional haploid embryos instead of mature pollen. The ability of these cells to change their development in response to environmental stimuli is an exceptional example of totipotency in plants. Discovering the triggers of embryo development in microspore cultures could lead to a greater understanding of the early stages of embryogenesis in plants and might be used to increase the range of crop plants to which microspore culture can be applied for the production of double haploid homozygous lines. The information might also help to define the general characteristics of pluripotent cells in any organism. In this review, the changes that occur in cellular organization and gene expression in early-stage microspore cultures of several species are discussed. Responding cells in these cultures enlarge, their nuclei are repositioned to their cell centres, and their cytoplasms become filled with fragmented vacuoles. We used flow cytometry to track cellul...

[1]  H. Spaink,et al.  Androgenic switch: an example of plant embryogenesis from the male gametophyte perspective. , 2005, Journal of experimental botany.

[2]  W. Newcomb,et al.  Microspore development inBrassica napus and the effect of high temperature on division in vivo and in vitro , 1993, Protoplasma.

[3]  A. Hetherington,et al.  The generation of Ca(2+) signals in plants. , 2004, Annual review of plant biology.

[4]  P. Vrinten,et al.  Characterization of cDNAs expressed in the early stages of microspore embryogenesis in barley (Hordeum vulgare) L. , 1999, Plant Molecular Biology.

[5]  H. Gabius,et al.  Dissection of the impact of various intracellular signaling pathways on stable cell aggregate formation of rat thymocytes after initial lectin-dependent cell association using a plant lectin as model and target-selective inhibitors , 1999, Molecular and Cellular Biochemistry.

[6]  E. Heberle‐Bors,et al.  De novo transcription of specific mRNAs during the induction of tobacco pollen embryogenesis , 1993, Sexual Plant Reproduction.

[7]  H. Dickinson,et al.  Microspore-derived embryos in Brassica: the significance of division symmetry in pollen mitosis I to embryogenic development , 2004, Sexual Plant Reproduction.

[8]  L. Martiny,et al.  Regulation of developmental pathways in cultured microspores of tobacco and snapdragon by medium pH , 2004, Planta.

[9]  W. Newcomb,et al.  Heat-shock proteins 70 kDa and 19 kDa are not required for induction of embryogenesis of Brassica napus L. cv. topas microspores. , 2003, Plant & cell physiology.

[10]  M. Tazawa,et al.  Is Ca2+ release from internal stores involved in membrane excitation in characean cells? , 2003, Plant & cell physiology.

[11]  Zhenbiao Yang,et al.  Analysis of the Small GTPase Gene Superfamily of Arabidopsis1 , 2003, Plant Physiology.

[12]  P. Chourey,et al.  Starch Biosynthesis during Pollen Maturation Is Associated with Altered Patterns of Gene Expression in Maize1 , 2002, Plant Physiology.

[13]  Neus Agell,et al.  Modulation of the Ras/Raf/MEK/ERK pathway by Ca(2+), and calmodulin. , 2002, Cellular signalling.

[14]  H. V. Van Onckelen,et al.  The Role of Auxin, pH, and Stress in the Activation of Embryogenic Cell Division in Leaf Protoplast-Derived Cells of Alfalfa1 , 2002, Plant Physiology.

[15]  V. Sharma,et al.  Ectopic Expression of BABY BOOM Triggers a Conversion from Vegetative to Embryonic Growth Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.001941. , 2002, The Plant Cell Online.

[16]  K. P. Pauls,et al.  Flow cytometric analysis of cellulose tracks development of embryogenic Brassica cells in microspore cultures , 2002 .

[17]  Zhenbiao Yang,et al.  The ROP2 GTPase Controls the Formation of Cortical Fine F-Actin and the Early Phase of Directional Cell Expansion during Arabidopsis Organogenesis Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.001537. , 2002, The Plant Cell Online.

[18]  J. Qiu,et al.  The Arabidopsis SPIKE1 Gene Is Required for Normal Cell Shape Control and Tissue Development Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.010346. , 2002, The Plant Cell Online.

[19]  E. Eliyahu,et al.  PKC in eggs and embryos. , 2001, Frontiers in bioscience : a journal and virtual library.

[20]  R. Dhindsa,et al.  Cold-activation of Brassica napus BN115 promoter is mediated by structural changes in membranes and cytoskeleton, and requires Ca2+ influx. , 2001, The Plant journal : for cell and molecular biology.

[21]  C. Dumas,et al.  Molecular characterisation of two novel maize LRR receptor-like kinases, which belong to the SERK gene family , 2001, Planta.

[22]  D. Verma,et al.  A Novel UDP-Glucose Transferase Is Part of the Callose Synthase Complex and Interacts with Phragmoplastin at the Forming Cell Plate , 2001, Plant Cell.

[23]  D. J. Carroll,et al.  Ca2+ signalling during fertilization of echinoderm eggs. , 2001, Seminars in cell & developmental biology.

[24]  C. Dumas,et al.  Fertilization in flowering plants. New approaches for an old story. , 2001, Plant physiology.

[25]  B. van Duijn,et al.  Insights into a key developmental switch and its importance for efficient plant breeding. , 2000, Plant physiology.

[26]  P. Benfey,et al.  ASYMMETRIC CELL DIVISION IN PLANTS. , 1999, Annual review of plant physiology and plant molecular biology.

[27]  W. Keller,et al.  Significance of preprophase bands of microtubules in the induction of microspore embryogenesis of Brassica napus , 1999, Planta.

[28]  D. Twell,et al.  Asymmetric division and cell-fate determination in developing pollen , 1998 .

[29]  L. Santella.  The role of calcium in the cell cycle: facts and hypotheses. , 1998, Biochemical and biophysical research communications.

[30]  K. P. Pauls,et al.  Flow Cytometric Characterization of Embryogenic and Gametophytic Development in Brassica napus Microspore Cultures , 1998 .

[31]  E. Heberle‐Bors,et al.  Initiation of microspore embryogenesis by stress , 1997 .

[32]  K. P. Pauls.  The utility of doubled haploid populations for studying the genetic control of traits determinated by recessive alleles , 1996 .

[33]  R. Quatrano,et al.  Fucus Embryogenesis: A Model to Study the Establishment of Polarity. , 1993, The Plant cell.

[34]  K. P. Pauls,et al.  Flow cytometric characterization of microspore development in Brassica napus , 1992 .

[35]  D. Bartels,et al.  Messenger-RNA and protein changes associated with induction of Brassica microspore embryogenesis , 1991, Planta.

[36]  K. Suprenant.  Unidirectional microtubule assembly in cell-free extracts of Spisula solidissima oocytes is regulated by subtle changes in pH. , 1991, Cell motility and the cytoskeleton.

[37]  S. M. Wolniak,et al.  1,2-Dioctanoylglycerol accelerates or retards mitotic progression in Tradescantia stamen hair cells as a function of the time of its addition. , 1990, Cell motility and the cytoskeleton.

[38]  D. Epel.  An Ode to Edward Chambers: Linkages of Transport, Calcium and pH to Sea Urchin Egg Arousal at Fertilization , 1989 .

[39]  J. Guern,et al.  Intracellular pH: Measurement and Importance in Cell Activity , 1989 .

[40]  W. Boss,et al.  Second messengers in plant growth and development , 1987 .

[41]  W. Jensen.  Fertilization in Flowering Plants. , 1973 .