Budding fission

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. 

In a series of experiments, we produced giant vesicles with dimension of several microns up to several millimeters by phase transfer processes [1,2]. Giant vesicles are often used as model membranes for biological cells. Due to their size, it is possible to investigate typical effects like budding, fission or membrane fusion by... 

Yeast Fungus whose thallus consists of single cells that multiply by budding or fission. 

Nasmyth In the case of the weel system, not very much is known about how fission yeast is doing it. In budding yeast, it is the level of Cln3. 

The budding yeast securin has what appears to be a single stable partner, a 180 kDa protein called Espl (Ciosk et al 1998). In fission yeast, Cut2 had previously been found to be associated with Cut 1, an Espl homologue (Funabiki et al 1996b). 

Hunt There are differences between budding and fission yeast in the importance ofPdsl. 

Nurse Another difference is that the mitotic cohesin persists in fission yeast meiosis, which is not the case in budding yeast. I think what is exciting about this, however, are the similarities, so we shouldn t get too worried by the differences. We have talked a lot about cohesin, but I wondered whether it might be worth having some discussion of the S phase suppression. 

Beach, D., Durkacz, B. and Nurse, P. (1982) Functionally homologous cell cycle control genes in budding and fission yeast. Nature, 300 (5894), 706-709. 

The time from one fission to the next fission, or from budding to budding, is the generation time t (h), and is approximately equal to the doubling time. Several examples of specific growth rates are given in Table 4.2. 

Cell division Fission or budding no mitosis Mitosis, including mitotic spindle centrioles in many species... 

When the pH of a suspension of microspheres of acidic proteinoid is raised by 1-2 units, diffusion of material from the interior to the exterior, fission into two particles, and the appearance of a double layer in the boundary are observed 2 Proteinoid microspheres shrink or swell on transfer to hypertonic or to hypotonic solutions respectively. Some experiments show that polysaccharides are retained under conditions in which monosaccharides diffuse out2. Some proteinoid microspheres possess the intrinsic capacity to grow by accretion, to proliferate through budding, and to form junctions 2). The morphology and other characteristics of proteinoid microspheres are altered by the inclusion of other materials such as polynucleotides, lipids or salts. 

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