Rocha D. M. auteur aut IRD Marques A. auteur aut IRD Andrade Cgtj auteur aut IRD Guyot Romain auteur aut IRD Chaluvadi S. R. auteur aut IRD Pedrosa-Harand A. auteur aut IRD Houben A. auteur aut IRD Bennetzen J. L. auteur aut IRD Vanzela A. L. L. auteur aut IRD text journalArticle eng text/pdf born digital access The functional cell of an asymmetric tetrad is selected according to its replication capability, while degenerative cells progress to multistep PCD, including mitotic disorder and DNA elimination.Members of the Cyperaceae family exhibit an asymmetric microsporogenesis that results in the degeneration of three out of four meiotic products. Efforts have been made previously to describe the resulting structure, named the pseudomonad, but mechanisms concerning the establishment of cell domains, nuclear development, and programmed cell death are largely unknown. Using the Rhynchospora genus as a model, evidence for cell asymmetry, cytoplasmic isolation, and programmed cell death was obtained by a combination of electron microscopic, cytochemical, immunocytochemical, in situ hybridization, and flow cytometric methods. Degenerative cells were identified at the abaxial region, with the cytoskeleton marking their delimitation from the functional domain after meiosis. After attempting to initiate cell division with an unreplicated genome and abnormal spindle assembly, these cells exhibited a gradual process of cytoplasmic contraction associated with hypermethylation of cytosines and differential loss of DNA. These results indicate that the asymmetric tetrad establishes a functional cell, where one nucleus is preferentially selected to survive. Degenerative haploid cells are then eliminated in a multistep process associated with mitotic disorder, non-random elimination of repetitive DNA, vacuolar cell death, and DNA fragmentation. specialized Asymmetric cell plate electron microscopy holocentromeres meiotic drive mitotic disorder pollen development vacuolar cell death 076 020 67 18 5391-5401 2016 0022-0957 https://www.documentation.ird.fr/hor/fdi:010068282 10.1093/jxb/erw300 0022-0957 [F B010068282] https://www.documentation.ird.fr/hor/fdi:010068282 https://www.documentation.ird.fr/intranet/publi/2016/11/010068282.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2016-12-06 2021-12-14 fdi:010068282 fre