Exam 16: Mutation, Repair, and Recombination

A point mutation in a gene's promoter will most likely cause the production of:

Three mutations were obtained in a bacterial gene.An antibody is available for the protein product of this gene.Both Northern analysis (RNA separated by electrophoresis,blotted,and probed with DNA)and Western analysis (proteins separated by electrophoresis,blotted,and probed with antibodies)were performed on the mutants.The results are summarized below. For each mutation,what kind of mutation occurred and how do you know it? a)Mutant 1 b)Mutant 2 c)Mutant 3

The rare enol form of thymine pairs with guanine.If a thymine enolization occurs during replication,what would be the mutational event?

A transversion somewhere within gene "B" in a laboratory plant results in the production of a mutant mRNA that is much longer than the wild type.This transversion is most likely located:

Mice that are homozygous for a complete deletion of the wild-type gene "T" develop multiple tumors in a variety of tissues very early in life.Gene "T" is most likely:

During mutagenic treatment with nitrous acid,an adenine deaminates to form hypoxanthine,which bonds like guanine.The mutational event would be:

A mouse is homozygous for a transversion that eliminated the splice site between the first exon and the first intron of gene "G." The resulting mutant mRNA is longer than the wild type,but the protein that it encodes is much shorter than its wild-type counterpart.Provide a logical and plausible explanation for these observations.

People who develop the hereditary form of retinoblastoma inherit:

A plant is homozygous for a point mutation in gene B.This plant produces wild-type B protein in wild-type amounts,but a more detailed analysis reveals that the B mRNA produced by this plant is two nucleotides shorter than wild type.The mutation is most likely a two base-pair deletion:

A small (one base pair)insertion in the middle of the coding region of a gene will cause a:

A mutation changes a codon from AAA (encoding lysine)to AGA (encoding arginine)in yeast,but no mutant phenotype is detected when the mutant strain is plated and grown on minimal or complete medium.This type of mutation is called:

In a classical genetic experiment,Newcombe spread E.coli cells on complete medium.After several generations of growth,he replica-plated the colonies onto two plates with complete medium plus a selective agent.Colonies on the first replica were left untouched,while on the second replica,they were respread,allowing bacteria from each colony to be "moved" to a new location on the plate.Significantly more mutants after spreading (resistant to the selective agent)were observed than if they had not been respread.The experiment was used to:

A Neurospora nonsense mutation known to be UAG is treated with two compounds,hydroxylamine and 5-bromouracil.Hydroxylamine (HA)causes G·C → A·T transitions,while 5-bromouracil causes T·A → C·G transitions.Which of these agents do you expect to induce revertants?