The (1,3)β-D-glucan synthase subunit Bgs1p is responsible for the fission yeast primary septum formation

[EN]Cytokinesis is a crucial event in the cell cycle of all living cells. In fungal cells, it requires coordinated contraction of an actomyosin ring and synthesis of both plasmatic membrane and a septum structure that will constitute the new cell wall end. Schizosaccharomyces pombe contains four ess...

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Bibliographic Details
Authors: Cortés, Juan Carlos G., Konomi, Mami, Martins, Ivone M., Muñoz, Javier, Moreno, María Belén, Osumi, Masako, Durán, Angel, Ribas, Juan Carlos
Format: article
Publication Date:2007
Country:España
Institution:Universidad de Salamanca (USAL)
Repository:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/125256
Online Access:http://hdl.handle.net/10366/125256
Access Level:Open access
Keyword:Glucan synthase
Cell wall
Morphogenesis
Septation
Fission Yeast
Morfogénesis
Levaduras
Tabicación celular
2415 Biología molecular
2414.10 Micología (levaduras)
2407 Biología celular
Description
Summary:[EN]Cytokinesis is a crucial event in the cell cycle of all living cells. In fungal cells, it requires coordinated contraction of an actomyosin ring and synthesis of both plasmatic membrane and a septum structure that will constitute the new cell wall end. Schizosaccharomyces pombe contains four essential putative (1,3)β-D-glucan synthase catalytic subunits, Bgs1p to Bgs4p. Here we examined the function of Bgs1p in septation by studying the lethal phenotypes of bgs1 + shut-off and bgs1 Δ cells and demonstrated that Bgs1p is responsible and essential for linear (1,3)β-D-glucan and primary septum formation. bgs1 + shut-off generates a more than 300-fold Bgs1p reduction, but the septa still present large amounts of disorganized linear (1,3)β-D-glucan and partial primary septa. Conversely, both structures are absent in bgs1 Δ cells, where there is no Bgs1p. The septum analysis of bgs1+-repressed cells indicates that linear (1,3)β-D-glucan is necessary but not sufficient for primary septum formation. Linear (1,3)β-D-glucan is the polysaccharide that specifically interacts with the fluorochrome Calcofluor white in fission yeast. We also show that in the absence of Bgs1p abnormal septa are formed, but the cells cannot separate and eventually die.