Lecture 6: Sex in Fungi Flashcards
1
Q
Requirements
A
- Recognition between cells of opposite mating types (MAT 1 and MAT 2)
2
Q
Hermaphroditic
A
Can act a male or female
3
Q
Term for male and female mating types
A
- Female- trichogyne
- Male- conidium/ hyphal cell
4
Q
Meiosis
A
Reduction and division, diploid meiocyte divides into 4 genetically different haploid gametes
5
Q
Differences between heterothallic and homothalic
A
Heterothallic:
* Has a reduced efficacy of purifying selection
* Increases the risk of undergoing genetic drift
Homothallic:
* Has a high efficacy of purifying selection
* Reduces the risk of undergoing genetic drift
6
Q
Mating strategies of homothallic species
A
- Homothallism
- Pseudohomothallism
- Bi-directoinal mating type switching
- Uni-directional mating type switching
- Unisexual reproduction
7
Q
psuedohomothallism
A
- Isolate can sexually reproduce without partner
- each cell has 2 nuclei
- Mat loci diff in each
- Opp mating identities in a single cell allows for sexual reproduction
8
Q
Bi-directional Mating type
A
- Sexually reproduce without partner
- Achieved through changing the mating of one of the daughter cells
- Both MAT1 and MAT2 cells in the same population
9
Q
Unidirectional Mating type
A
- MAT2 inserted into MAT1 gene, therefore MAT2protein cannot be made
- Cell division causes deletion of MAT2 info
- Only MAT1 present and protein is made, cell identifies as MAT1
- MAT1 and MAT2 can now mate and produce offspring
10
Q
Unisexual reproduction
A
- Appears both homothallic and heterothalli
- sexual reproduction in single isolate that harbours genes associated with only a single mating type
11
Q
Importance of sexual reproduction
A
- eliminate deleterios mutations
Genetic recombination
Genetic variability
