What complications might arise from genetic screens targeting an organ that differentiates late in development?
A. The DNA of late development genes is usually highly condensed and thus inaccessible for mutagenesis.
b. Genes controlling adult structures can be important in earlier stages of development, and their mutations may be lethal and thus hidden from observation.
c. The sequence of late development genes is highly variable, so it is difficult to obtain loss-of-function mutant phenotypes.
When the S. cerevisiae genome was sequenced and surveyed for possible genes, only about 40% those genes had been previously identified identified in forward genetic screens. This left about 60% of predicted genes with no known function, leading some to dub the genes fun (function unknown) genes.
As an approach to understanding the function of a certain fun gene, you wish to create a loss-of-function allele. How will you accomplish this?
A. P element insertions
B. transformation and homologous recombination
c. transposon insertions
d. inversion and homologous recombination
You wish to know the physical location of the encoded protein product. How will you ascertain such information?
A. TILLING
B. translational fusion with GFP gene
c. transcriptional fusion with GFP gene
d. PCR analysis
1. Option B is correct
Genes controlling adult structures can be important in earlier
stages of development, and their mutations may be lethal and thus
hidden from observation
2. Option B is correct
If we want to create a mutation in a known gene, we have to use
homologous recombination system. Homologous recombination can be
used to replace a known WT sequence with a mutant version.
3. Option B is correct
If we want to determine the physical location of a protein, we have
to create a translational fusion with a reporter gene such as GFP
or RFP.
What complications might arise from genetic screens targeting an organ that differentiates late in development? A....
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