The complimentation test is used to find out if mutations are allelic or non allelic
In what circumstances will a Complimentation Test give a false result?
When the mutation is recessive
When the mutation is dominant
When the mutated gene is part of a complex
Where proteins form multimers
Genotypes M1 & M2 are bred together, and a Wild Type result is obtained- are the mutations allelic
No- as the presentation of a wild type phenotypes shows there is at least one dominant wild type allele for each gene
Yes- The two mutations on the same allele are able to compliment each other sufficiently to produce a wild type phenotype
If M3 and M2 are bred together and they present as M2, what does this tell us about the mutation's location?
They are on the same allele- there is no dominant wild type allele to mask their activity
They are on separate alleles, but M2 has a far greater effect than previously thought
According to the above table, which mutations are allelic
M9 & M4
M8 & M6
All of the above
A Complimentation Test can be fooled if the mutant protein can form a functioning heterodimer with the wild type protein
One gene is said to be epistatic to another if...
The presence of a double mutant exhibits the phenotype of the mutant gene
The presence of the wild type masks the phenotype of the mutant gene
A genes expression causes a change in the expression of another gene further down the pathway
Where are epistatic genes usually found in substrate dependent pathways?
A substrate dependent pathway is a series of positive and negative regulators that act on one another of the final product
This image is of a Switch Regulatory Pathway
Why should null alleles be used for epistatic analysis (i.e how to find out the order of gene function in a pathway)
The masking of alleles downstream becomes obvious
They are easier to make than hypomorphic alleles
They can be used for both Substrate Dependent and Switch pathways
How do we identify that the pathway effected by the (epistatic) mutation is a Switch Regulatory pathway?
If the mutation prevents the production of the final product
If the phenotype of a double mutant is different to the phenotype of either single mutant
The Rif1 & Rif2 strains are both causes lengthened telomeres, as shown in the diagram. Based on the Rif1/Rif2 double mutation, which of the two availible pathways (shown) is likely to be the one used?