Geneticist for a Day
Gel Electrophoresis | Multimedia | Activities
Gel Electrophoresis - Activity 1 - Geneticist for a Day - Answers
Gel Electrophoresis - Activity 1 - Geneticist for a Day - Answers
Goal: Have students be able to evaluate a gel electrophoresis in a research science setting
Materials: Pen or pencil, paper
The scenario: You are a scientist studying the mouse gene smu, which codes for the protein SMUase. You want to collect a lot of SMUase, but the mice do not make the protein quick enough, so you decide to create a plasmid.
You make the plasmid with the smu gene, and other necessary markers, and decide to insert it into e. coli bacteria. You heat up the bacteria to get the plasmid inside and near the DNA, but you cannot be sure that the plasmid has inserted itself into the E. coli’s DNA.
You know that your gene contains the sequence GGGAATTCCG, so you decide to perform an electrophoresis on the e. coli DNA, then use a probe to determine if your gene has been inserted into the e.coli DNA.
The DNA the probe binds to is in red. The size marker is in blue.
Click for a larger picture
Questions:
What sequence would the probe have?
What must be done to the e. coli before the electrophoresis?
Did your plasmid make it into the DNA? Why or why not?
Materials: Pen or pencil, paper
The scenario: You are a scientist studying the mouse gene smu, which codes for the protein SMUase. You want to collect a lot of SMUase, but the mice do not make the protein quick enough, so you decide to create a plasmid.
You make the plasmid with the smu gene, and other necessary markers, and decide to insert it into e. coli bacteria. You heat up the bacteria to get the plasmid inside and near the DNA, but you cannot be sure that the plasmid has inserted itself into the E. coli’s DNA.
You know that your gene contains the sequence GGGAATTCCG, so you decide to perform an electrophoresis on the e. coli DNA, then use a probe to determine if your gene has been inserted into the e.coli DNA.
The DNA the probe binds to is in red. The size marker is in blue.

Click for a larger picture
Questions:
What sequence would the probe have?
What must be done to the e. coli before the electrophoresis?
Did your plasmid make it into the DNA? Why or why not?