caa a22 4500 477053270 CHVBK 20180405111343.0 cr unu---uuuuu 170330e19960501xx s 000 0 eng 10.1007/BF02221394 doi (NATIONALLICENCE)springer-10.1007/BF02221394 Nuclear cytoplasmic domains, microtubules and organelles in microsporocytes of the slipper orchid Cypripedium californicum A. Gray dividing by simultaneous cytokinesis [Elektronische Daten] [Roy Brown, Betty Lemmon, R. Brown, B. Lemmon] Microsporocytes of the slipper orchidCypripedium californicum A. Gray divide simultaneously after second meiosis. The organization and apportionment of the cytoplasm throughout meiosis are functions of nuclear-based radial microtubule systems (RMSs) that define domains of cytoplasm - a single sporocyte domain before meiosis, dyad domains within the undivided cytoplasm after first meiosis, and four spore domains after second meiosis. Organelles migrate to the interface of dyad domains in the undivided cytoplasm after first meiotic division, and second meiotic division takes place simultaneously on both sides of the equatorial organelle band. Microtubules emanating from the telophase II nuclei interact to form columnar arrrays that interconnect all four nuclei, non-sister as well as sister. Cell plates are initiated in these columns of microtubules and expand centrifugally along the interface of opposing RMSs, coalescing in the center of the sporocyte and joining with the original sporocyte wall at the periphery to form the tetrad of microspores. Organelles are distributed into the spore domains in conjunction with RMSs. These data, demonstrating that cytokinesis in microsporogenesis can occur in the absence of both components of the typical cytokinetic apparatus (the preprophase band of microtubules which predicts the division site and the phragmoplast which controls cell-plate deposition), suggest that plant nuclei have an inherent ability to establish a domain of cytoplasm via radial microtubule systems and to regulate wall deposition independently of the more complex cytokinetic apparatus of vegetative cells. Springer-Verlag, 1996 Cytokinesis nationallicence Microtubules nationallicence Microsporogenesis nationallicence Orchids nationallicence Phragmoplast nationallicence Pollen nationallicence Brown Roy Department of Biology, University of Southwestern Louisiana, 70504-2451, Lafayette, LA, USA aut Lemmon Betty Department of Biology, University of Southwestern Louisiana, 70504-2451, Lafayette, LA, USA aut Brown R. Department of Biology, University of Southwestern Louisiana, 70504-2451, Lafayette, LA, USA aut Lemmon B. Department of Biology, University of Southwestern Louisiana, 70504-2451, Lafayette, LA, USA aut Sexual Plant Reproduction Springer-Verlag 9/3(1996-05-01), 145-152 0934-0882 9:3<145 1996 9 497 https://doi.org/10.1007/BF02221394 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02221394 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Brown Roy Department of Biology, University of Southwestern Louisiana, 70504-2451, Lafayette, LA, USA aut NATIONALLICENCE 700 1- Lemmon Betty Department of Biology, University of Southwestern Louisiana, 70504-2451, Lafayette, LA, USA aut NATIONALLICENCE 700 1- Brown R. Department of Biology, University of Southwestern Louisiana, 70504-2451, Lafayette, LA, USA aut NATIONALLICENCE 700 1- Lemmon B. Department of Biology, University of Southwestern Louisiana, 70504-2451, Lafayette, LA, USA aut NATIONALLICENCE 773 0- Sexual Plant Reproduction Springer-Verlag 9/3(1996-05-01), 145-152 0934-0882 9:3<145 1996 9 497 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer