Virtual Labs

Immunoprecipitation of protein from Cell Lysate using Antibody

1. Which of the following statements about immunoprecipitation (IP) is NOT true?

a: IP is a method that uses an antibody that binds to a particular protein to isolate and concentrate that protein from a sample. Explanation

Explanation

b: Because Protein A or Protein G beads attach to the Fc region of antibodies, making it easier to capture the antibody-protein complex, they are frequently utilized in IP. Explanation

Explanation

c: Because immunoprecipitation only enables the isolation of individual proteins, it cannot be used to investigate protein-protein interactions. Explanation

Explanation

d: The washing procedure, which aids in removing other components and proteins that are not particularly bound from the beads, is one of the most important procedures in IP. Explanation

Explanation

2. Which of the following sums up immunoprecipitation's (IP) main goal the best?

a: To enhance particular DNA sequences Explanation

Explanation

b: To calculate the protein content of a sample Explanation

Explanation

c: Sorting proteins according to how electrically charged they are Explanation

Explanation

d: Using an antibody to separate a particular protein from a complicated combination Explanation

Explanation

3. Of the following, which one is crucial to take into account when choosing an antibody for immunoprecipitation?

a: The target protein's isoelectric point Explanation

Explanation

b: The antibody's solubility in water-based solutions Explanation

Explanation

c: The antibody's affinity and specificity for the target protein Explanation

Explanation

d: The antibody's molecular weight Explanation

Explanation

4. In the immunoprecipitation (IP) process, what provides stable support for immobilizing the antibody-protein complex?

a: Agarose gel Explanation

Explanation

b: Magnetic, agarose or sepharose beads coupled with Protein A or G Explanation

Explanation

c: Centrifugation pellets Explanation

Explanation

d: Wash buffer Explanation

Explanation

5. What is the primary reason for using Protein A or G in the immunoprecipitation process?

a: They directly bind to the target antigen. Explanation

Explanation

b: They have a high affinity for immunoglobulins and bind to the Fc region of the antibody. Explanation

Explanation

c: They act as a stabilizing agent for the antigen. Explanation

Explanation

d: They are used to wash away unbound proteins. Explanation

Explanation

6. During the immunoprecipitation procedure, what is the role of the centrifugation step?

a: To mix the antibody and antigen together Explanation

Explanation

b: To bind the antibody to the beads Explanation

Explanation

c: To separate the bead-bound complex from the supernatant Explanation

Explanation

d: To elute the antibody-protein complex from the beads Explanation

Explanation

7. What does the term 'high affinity' refer to in the context of Immunoprecipitation?

a: The strong binding interaction between the antibody and the target antigen Explanation

Explanation

b: The strong binding interaction between the antigen and the beads Explanation

Explanation

c: The ability of the beads to bind to multiple antigens Explanation

Explanation

d: The ability of the buffer to maintain pH stability Explanation

Explanation

8. In co-immunoprecipitation (Co-IP), what additional information can be obtained compared to standard Immunoprecipitation (IP)?

a: The identity of the target antigen Explanation

Explanation

b: The interaction partners or associated protein complexes of the target antigen Explanation

Explanation

c: The structure of the antibody Explanation

Explanation

d: The pH of the buffer solution used Explanation

Explanation

9. What is the function of the wash buffer in the immunoprecipitation process?

a: To dissociate the antibody-antigen complex Explanation

Explanation

b: To remove unbound complexes, antibodies, or impurities Explanation

Explanation

c: To stabilize the pH during the reaction Explanation

Explanation

d: To bind to the Fc region of the antibody Explanation

Explanation

10. Which type of Immunoprecipitation is specifically used to study protein-RNA interactions?

a: Co-immunoprecipitation (Co-IP) Explanation

Explanation

b: Chromatin immunoprecipitation (ChIP) Explanation

Explanation

c: RNA immunoprecipitation Explanation

Explanation

d: Reverse Immunoprecipitation Explanation

Explanation

11. What assumption is made when proteins are co-precipitated in Co-IP?

a: The proteins are contaminants Explanation

Explanation

b: The proteins are unrelated to the target antigen Explanation

Explanation

c: The proteins are functionally related to the target antigen at the cellular level Explanation

Explanation

d: The proteins are involved in the pH stabilization of the buffer Explanation

Explanation

12. Which analysis techniques can be used to examine the separated complexes and antigens after Immunoprecipitation?

a: Chromatography and Spectrophotometry Explanation

Explanation

b: SDS-PAGE, staining, Western Blotting, or Mass Spectrometry Explanation

Explanation

c: ELISA and PCR Explanation

Explanation

d: Flow Cytometry and Microscopy Explanation

Explanation

13. What distinguishes Phospho-specific Immunoprecipitation from other types of IP?

a: It isolates DNA instead of proteins. Explanation

Explanation

b: It specifically isolates and studies phosphorylated proteins. Explanation

Explanation

c: It uses a different type of antibody. Explanation

Explanation

d: It does not require beads for immobilization Explanation

Explanation