Spore number control and breeding in Saccharomyces cerevisiae: a key role for a self-organizing system.
Spindle pole bodies (SPBs) provide a structural basis for genome inheritance and spore formation during meiosis in yeast. Upon carbon source limitation during sporulation, the number of haploid spores formed per cell is reduced. We show that precise spore number control (SNC) fulfills two functions. SNC maximizes the production of spores (1-4) that are formed by a single cell. This is regulated by the concentration of three structural meiotic SPB components, which is dependent on available amounts of carbon source. Using experiments and computer simulation, we show that the molecular mechanism relies on a self-organizing system, which is able to generate particular patterns (different numbers of spores) in dependency on one single stimulus (gradually increasing amounts of SPB constituents). We also show that SNC enhances intratetrad mating, whereby maximal amounts of germinated spores are able to return to a diploid lifestyle without intermediary mitotic division. This is beneficial for the immediate fitness of the population of postmeiotic cells.
Taxis
Christof
C
The European Molecular Biology Laboratory, D-69117 Heidelberg, Germany.
Keller
Philipp
P
Kavagiou
Zaharoula
Z
Jensen
Lars Juhl
LJ
Colombelli
Julien
J
Bork
Peer
P
Stelzer
Ernst H K
EH
Knop
Michael
M
D002244:Carbon; D002503:Centromere / Q000648:ultrastructure; D003198:Computer Simulation; D003593:Cytoplasm / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005799:Genes, Dominant; D005800:Genes, Fungal; D008040:Genetic Linkage; D005838:Genotype; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006238:Haploidy; D008540:Meiosis; D008854:Microscopy, Electron; D018715:Microscopy, Video; D008954:Models, Biological; D009154:Mutation; D016366:Open Reading Frames; D010957:Plasmids / Q000378:metabolism; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology; D012984:Software; D008941:Spindle Apparatus; D013172:Spores, Fungal / Q000502:physiology*; D013997:Time Factors
D029701:Saccharomyces cerevisiae Proteins; D049452:Green Fluorescent Proteins; D002244:Carbon