Question

Go to the RCSB site for the Protein Data Bank (http://www.rcsb.org/pdb). Give a brief description of the molecule prefoldin, which can be found under chaperones.

Short answer

Prefoldin is a molecular chaperone that assists in protein folding by stabilizing unfolded proteins and delivering them to other chaperones.

Step-by-step solution

- Access the RCSB Protein Data Bank Website

Open your web browser and go to http://www.rcsb.org/pdb.

- Use the Search Feature

In the search bar located at the top of the homepage, type in 'prefoldin chaperones' and hit Enter.

- Select the Appropriate Entry

From the search results, look for an entry under the chaperones category that matches 'prefoldin'. Click on the corresponding PDB ID to access detailed information about the molecule.

- Read the Brief Description

On the entry page, you will find a summary or abstract that provides a brief description of the prefoldin molecule, including its structure and function. Note key details such as its role in assisting the folding of other proteins.

Key concepts

prefoldin

Prefoldin is an important molecular chaperone that assists in the correct folding of proteins. Found under the chaperones category in the Protein Data Bank (PDB), it plays a crucial role in maintaining cellular function by stabilizing nascent polypeptides and delivering them to other folding machineries like the chaperonin TRiC/CCT complex.
Prefoldin itself is a complex made up of multiple subunits. Each subunit contributes to creating a structure that can bind to partially folded proteins. This binding helps prevent misfolded proteins, which can be harmful to the cell. Prefoldin is essential for the health of eukaryotic cells, particularly in processes like cytoskeleton assembly and DNA replication.

molecular chaperones

Molecular chaperones are proteins that aid other proteins in achieving their proper 3D structure. This proper folding is vital for the protein's biological function. They do not form part of the final structure of the protein but help in the folding process.
There are different types of molecular chaperones, like Hsp70, Hsp90, and small heat shock proteins. Prefoldin is a member of this group. They often work in stressful cellular conditions where proteins are more prone to misfolding.
Chaperones function by binding to the nascent or unfolded polypeptides and stabilizing them, preventing premature folding and aggregation. After binding, they often release the partially folded protein to other chaperones for further folding.

• Assist in protein folding
• Prevent protein misfolding and aggregation
• Act under stressful conditions

protein folding

Protein folding is the process through which a protein achieves its functional 3D shape. This process is crucial because a protein’s function is directly related to its structure.
The sequence of amino acids in a protein determines its final shape. Initially, the polypeptide chain forms simple structures like alpha helices and beta sheets. These simple structures then fold into more complex ones.
Proper folding can sometimes require the assistance of molecular chaperones. Without help, proteins might misfold, leading to non-functional or harmful aggregates. Misfolded proteins are linked to various diseases, like Alzheimer's and Parkinson's.

• Initial polypeptide sequence determines final structure
• Formation of simple structures like alpha helices and beta sheets
• Assistance by molecular chaperones
• Improper folding can lead to disease