Saccharomyces cerevisiae sporulation

Fig. 2.6 The moqjhological events of sporulation in Saccharomyces cerevisiae. (a) starved cell V, vacuole LG, lipid granule ER, endoplasmic reticulum CW, cell wall M, mitochondrion S, spindle pole SM, spindle microtubules N, nucleus NO, nucleolus, (b) Synaptonemal complex (SX) and development of polycomplex body (PB) along with division of spindle pole body in (c). (d) First meiotic division which is completed in (e). (f) Prepararation for meiosis II. (g) Enlargement of prospore wall, culminating in enclosure of separate haploid nuclei (h). (i) Spore coat (SC) materials produced and deposited, giving rise to the distinct outer spore coat (OSC) seen in the completed spores of the mature ascus (j). Reproduced from the review by Dickinson (1988) with permission from Blackwell Science Ltd.

Clancy, M. J., Buton-Magee, B., Straight, D. J., Kennedy, A. L., Partridge, R. M., and Magee, P. T. (1983). Isolation of genes expressed preferentially during sporulation in the yeast Saccharomyces cerevisiae. Proc. Natl Acad. Scl U.S.A. 80, 3000-3004. 

Fast, D. (1973). Sporulation synchrony of Saccharomyces cerevisiae grown in various carbon sources. J. Bacterial 116, 925-930. 

Gottlin-Ninfa, E., and Kaback, D. B. (1986). Isolation and functional analysis of sporulation-induced transcribed sequences from Saccharomyces cerevisiae. Mol. Cell. Biol. 6, 2185-2197. 

Moens, P. B. and Rapport, E. (1971). Synaptic structures in the nuclei of sporulating yeast, Saccharomyces cerevisiae (Hansen). J. Cell Sci. 9, 665-677. 

Percival-Smith, A., and Segall, J. (1984). Isolation of DNA sequences preferentially expressed during sporulation in Saccharomyces cerevisiae. Mol. Cell Biol. 4,142-150. 

M.S.Esposito, Decompartmentalization of erythromycin sensitivity during sporulation of Saccharomyces cerevisiae Genetic control by chromosomal and mitochondrial genes. Submitted to J. Bacteriol. (1979). 

The overall life cycle of a particular yeast Saccharomyces (S.) cerevisiae, is summarised in Fig. S.6 which shows how it is possible for the cells to fuse to form various cell and spore types. The figure shows the possible types of reproduction in yeast. Generally, industrial strains of S. cerevisiae, brewers yeast, reproduce by budding/ fission processes and only sporulate under specialised conditions. However, many strains of yeast are capable of cell fusion to form spores or cells with increased genetic complements. Such strains have many sets of chromosomes and are termed polyploid. Active fermentation of industrial strains involves growth by mitotic division and nutrient depletion which results in stationary cells with little or no spore formation. 

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