QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

doi: 10.1242/10.1242/jcs.00085

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Cortés, J. C. G. Articles by Ribas, J. C. Search for Related Content PubMed PubMed Citation Articles by Cortés, J. C. G. Articles by Ribas, J. C.

Localization of the (1,3)ß-D-glucan synthase catalytic subunit homologue Bgs1p/Cps1p from fission yeast suggests that it is involved in septation, polarized growth, mating, spore wall formation and spore germination

¹ Instituto de Microbiología Bioquímica and Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Salamanca, 37007 Salamanca, Spain
² Department of Biology, Faculty of Science and Engineering, Konan University, Okamoto 8-9-1, Kobe 658-8501, Japan

View larger version (96K): [in a new window]   Fig. 1. Genetic interactions of S. pombe cps1-12 mutant with the actin mutant cps8-188 and with cdc septation mutants. Phase-contrast and Calcofluor white UV staining micrographs of log-phase cells grown on YES liquid medium at 25°C and shifted to different temperatures. Cells are shown grown at the temperature that reveals in each case the most apparent difference between single and double mutant phenotypes (8 hours at 30°C for cps8-188, 8 hours at 31°C for cdc16-116 and 6 hours at 34°C for cdc14-118 single and double cps1-12 mutants). The phenotype of the cps1-12 cps8-188 double mutant is more aggravated than that of the corresponding single mutants, while the phenotype of the cps1-12 cdc14-118 double mutant resembles that of the cdc14-118 single mutant, and the phenotype of the cps1-12 cdc16-116 double mutant is similar to that of the cps1-12 single mutant. The cps1-12 single mutant cells were grown at 34°C, but a weaker phenotype was obtained at 30 or 31°C. Cells were centrifuged, suspended in 50 µg/ml Calcofluor white and directly observed for phase-contrast and Calcofluor white staining.

View larger version (66K): [in a new window]   Fig. 2. Bgs1p localizes to the growing areas, to one or both poles, and to the contractile ring and septum. (A) Calcofluor white staining and GFP-Bgs1p localization along the mitotic cell cycle. (B) Detail of Calcofluor white staining and GFP-Bgs1p localization to the contractile ring and along the plasma membrane during septum formation. Early-logarithmic phase cells (GFP-bgs1+ bgs1), grown on YES liquid medium at 28°C, were visualized for GFP and Calcofluor white staining. Calcofluor white was added at 50 µg/ml following immediate examination of the cells. Cells representative of each cell cycle step were selected and aligned to show a cell cycle progression.

View larger version (72K): [in a new window]   Fig. 3. Bgs1p localization during septation depends on the medial ring formation and localization, and on proteins that form the septation initiation network. Calcofluor white staining and GFP-Bgs1p localization in different cdc septation mutants. GFP-bgs1+ bgs1 mutant cells were grown as in Fig. 2, shifted to 37°C for 3 hours (mid1-366) or 4 hours (cdc3-6, cdc11-119 and cdc14-118) or to 32°C for 5 hours (cdc15-140 and cdc16-116), and visualized for GFP and Calcofluor white staining. Cells representative of the different mutant phenotypes are shown.

View larger version (76K): [in a new window]   Fig. 4. Bgs1p does not localize to the contractile ring during or after mitosis in the septation initiation network mutants cdc11-119 and cdc14-118. GFP-bgsl+ bgsl mutant cells were grown as in Fig. 2, shifted to 37°C and collected at different times (2.5, 3.5, 4.5 and 5.5 hours). Cells were ethanol fixed and analyzed for GFP and Calcofluor white/Hoechst staining. Cells representative of the mutant phenotypes at different times, including cells displaying a partial septum made before expressing the mutant phenotype, are shown.

View larger version (83K): [in a new window]   Fig. 5. Bgs1p localizes to all around the cell and septum and to regions of altered cell wall deposition in the actin mutant cps8-188. GFP-bgs1+ bgs1 mutant cells were grown as in Fig. 2, shifted to 32°C for 5 hours or to 37°C for 3 or 6 hours, and examined for GFP and Calcofluor white staining. Cells representative of the different mutant phenotypes at each temperature and incubation time are shown.

View larger version (54K): [in a new window]   Fig. 6. Bgs1p localizes to the altered growing ends and septa in the end marker mutant strains tea1-1, tea2-1 and tea2-1 cdc11-119. GFP-bgs1+ bgs1 mutant cells were grown as in Fig. 2, shifted to 37°C for 6 hours (tea2-1 cdc11-119) or 8 hours (tea1-1 and tea2-1), and examined for GFP and Calcofluor white staining. Cells representative of the different mutant phenotypes are shown.

View larger version (76K): [in a new window]   Fig. 7. Bgs1p localization during the sexual phase of the life cycle suggests that it is involved in mating projection synthesis, cell fusion control and forespore and spore wall synthesis. Homothallic GFP-bgs1+ bgs1 h90 cells grown at 28°C in EMM liquid medium until early-stationary phase were collected, transferred onto a SPA plate and incubated at 28°C. Samples were taken after 3, 5, 8, 24 and 48 hours, resuspended in EMM liquid medium containing 50 µg/ml Calcofluor white, and visualized for GFP and Calcofluor white staining. Cells and zygotes representative of each mating and sporulation step were selected and aligned to show a sexual phase progression.

View larger version (62K): [in a new window]   Fig. 8. Bgs1p localizes around the spore during isotropic growth, to the growing pole during spore germination, and to the contractile ring and septum during cytokinesis of the first cell. Homothallic GFP-bgs1+ bgs1 h90 strain was grown and sporulated as in Fig. 7. Cells were incubated on SPA plates at 28°C for 7 days to allow most of the asci to spontaneously lyse and liberate the spores. The culture was checked to confirm that most of the spores were released. The spores were collected, incubated in YES liquid medium at 28°C, and samples were taken at 5 and 9 hours. Calcofluor white was added (50 µg/ml final concentration) and the spores were examined for GFP and Calcofluor white staining. Spores representative of each germination step were selected and aligned to show an ordered germination process.