Keratin 7

Structure and Function

What does Keratin do?

 In general Keratin is the protein that protects the epithelial cells from damage and stress that could kill the cell.

 Keratins can also help with cell signaling.

 Keratins can help a cell go through apoptosis (intentional cell death)

Specifically, what does Keratin 7 do?

 It can be found in kangaroo rat liver cells.

 Its expression is regulated by retinoic acid.

 They can also be found in bladder cells, mammary glands, and lung alveoli, and kidney cells.†

What are epithelial cells?

 Epithelial cells are cells that are on the outside of the body and on the outside of body organs.†

 They transport ions, absorb fluid, and secrete fluid.

The picture above is a stained image of Keratin 7. It was taken from the webpage hyperlinked below as k-7.† It is a fairly lengthy structure in comparison to the structures around it.

Amino Acid Sequence of Keratin:

 On the next page is the complete amino acid sequence for the gene that codes for Keratin 67 (a type of keratin found in humans that is similar to Keratin 7).

The Molecular Weight of Keratin 7:

 The average molecular weight of Keratin-7 is 54kD (kiloDaltons).

 In one case, the human molecular weight of Keratin 7 was 51.4 kD.

The Chromosome Location of Keratin 7:

 The protein Keratin 7 is located at

†††††††††† 12q12-q14

 This means that it is located on the 12th human chromosome.

Structure of Keratin 7:

 Keratin 7 is a protein that makes 8nm segments of intermediate filaments in the epithelial cells.†

 Normally the Keratin 7 proteins have 489 amino acids.

 In humans, the amino acid count for Keratin 7 is 469.†

 The protein Keratin 7 has been found to have 6 exons, but more recently, it was determined to have 9 exons.†


This is an image of the intermediate filaments of a Keratin protein.† They are long and close together for support.

It is from the second link listed on the home page.

The Structure of Keratin 7 and the Function of Keratin 7

The structure of Keratin 7 helps it to function.† The long intermediate filaments may serve as support for† the epithelial cell that the Keratin exists in. The structure of the protein Keratin 7 allows it to function as cytoskeleton and support its cell.††