[15] Tagging Proteins- HA, FLAG, and GFP

Question 1

What are protein tags?

Answer 1

Markers attached to proteins to aid in their detection or purification.

Question 2

What is the purpose of tagging proteins?

Answer 2

• Detection
• Purification
• Visualization

Question 3

Give examples of protein tags.

Answer 3

• HA tag
• FLAG tag
• GFP (Green Fluorescent Protein)

Question 4

Define the HA tag.

Answer 4

A short peptide derived from the influenza hemagglutinin protein, commonly used in protein tagging.

Question 5

Define the FLAG tag.

Answer 5

An octapeptide protein tag designed for antibody recognition in various assays.

Question 6

How are protein tags attached to the protein of interest?

Answer 6

By genetically engineering the protein’s gene to include the sequence encoding the tag.

Question 7

Why are HA and FLAG tags commonly used?

Answer 7

They are small, unlikely to interfere with protein function, and have high-affinity antibodies available for detection.

Question 8

What are the considerations when choosing a protein tag?

Answer 8

• Size and potential impact on protein function
• Available antibodies for detection
• Compatibility with experimental conditions

Question 9

GFP - Initials

Answer 9

Green Fluorescent Protein

Question 10

What is GFP used for?

Answer 10

As a tag in biological research, allowing for direct visualization of the protein of interest.

Question 11

What’s the advantage of using GFP as a protein tag?

Answer 11

GFP can be visualized directly because it fluoresces green when exposed to blue or ultraviolet light.