title: The meiosis-specific nuclear passenger protein is required for proper assembly of forespore membrane in fission yeast.
abstract: Sporulation, gametogenesis in yeast, consists of meiotic nuclear division and spore morphogenesis. In the fission yeast Schizosaccharomyces pombe, the four haploid nuclei produced after meiosis II are encapsulated by the forespore membrane (FSM), which is newly synthesized from spindle pole bodies (SPBs) in the cytoplasm of the mother cell as spore precursors. Although the coordination between meiosis and FSM assembly is vital for proper sporulation, the underlying mechanism remains unclear. In the present study, we identified a new meiosis-specific protein Npg1, and found that it was involved in the efficient formation of spores and spore viability. The accumulation and organization of the FSM was compromised in npg1-null cells, leading to the error-prone envelopment of nuclei. Npg1 was first seen as internuclear dots and translocated to the SPBs before the FSM assembled. Genetic analysis revealed that Npg1 worked in conjunction with the FSM proteins Spo3 and Meu14. These results suggest a possible signaling link from the nucleus to the meiotic SPBs in order to associate the onset of FSM assembly with meiosis II, which ensures the successful partitioning of gametic nuclei.
authors.affiliation: Department of Biological Sciences, Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba, Ibaraki 305-8577, Japan masaktakaine@gmail.com knakano@biol.tsukuba.ac.jp.
authors.forename: Masak
authors.initials: M
authors.lastname: Takaine
authors.affiliation: Department of Biology, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Imada
authors.affiliation: Department of Biological Sciences, Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Numata
authors.affiliation: Department of Biology, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Department of Biological Sciences, Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba, Ibaraki 305-8577, Japan masaktakaine@gmail.com knakano@biol.tsukuba.ac.jp.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Nakano
mesh_terms: D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D002467:Cell Nucleus / Q000502:physiology*; D015966:Gene Expression Regulation, Fungal / Q000235:genetics; D055786:Gene Knockout Techniques; D008540:Meiosis / Q000235:genetics / Q000502:physiology*; D009024:Morphogenesis / Q000235:genetics; D021381:Protein Transport / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D012568:Schizosaccharomyces / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D064048:Spindle Pole Bodies / Q000378:metabolism*; D013172:Spores, Fungal / Q000235:genetics
chemical_list: D018797:Cell Cycle Proteins; C483712:Meu14 protein, S pombe; C051095:SSP1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; C000602592:nuclear passenger protein-1, S pombe
keywords: Fission yeast; Forespore membrane; Meiosis; Spindle pole body; Sporulation