Experiments on spore formation in diploid cells of Saccharomyces cerevisiae
Diploid yeast cells induce meiosis and spore formation when they are starved of both nitrogen and carbon sources. At this point, their chromosomes replicate and undergo a secondary division to produce a haploid nucleus.
Operation method
basic program
Materials and Instruments
Yeast Move I. Spore formation on plates For more product details, please visit Aladdin Scientific website.
YPD
Petri dish Incubator
1. Pick or selectively inoculate single colonies of yeast from a plate onto a spore forming plate.If there is no need for selective viability, cells can be pre-grown on YPD plates for a few days before being transferred to spore forming plates. Individual colonies can be grown on YPD plates for 3 to 4 days, while for small clumps of cells, they can be grown on the plate for 2 days.This pre-growth is not necessary, but it allows for a somewhat more efficient spore formation.When transferring yeast cells, a small number of cells should be used to coat a relatively large area of a spore-forming plate, and clumps of inoculum should not be seen.2. Incubate at 25°C for 4 days.3. Put a drop of water on the slide, pick a small number of cells diluted in water, and observe under a microscope with a magnification of 250×~400×, that is to say, you can see the tetrasporangium spores suspended in water.II. Spore formation in liquid medium1. In a suitable culture vessel, add YPD medium to culture, and wait for the spore-forming diploid cells to grow until the OD600 is 2.5~3.0.
2. Transfer 1 ml of culture medium to a single-use sterile 15 ml polypropylene tube and centrifuge at 12 000 g for 5 min.
3. Pour off the supernatant, resuspend the cells with 5 ml of water, and centrifuge according to step 2.
4. Pour off the supernatant and resuspend the cells in 1 ml of spore-forming liquid medium supplemented with the nutrients required for the specific diploid cells.5. Incubate at 30°C and above 350 r/min for 2-3 days and examine spore formation under a microscope.