Protein family

Protein family is a group of proteins that share a common evolutionary origin, reflected by their related functions and similarities in sequence or structure. The concept of protein families was first introduced in the 1970s as a way to categorize proteins based on their structural and functional similarities.

Definition

A protein family is defined by the possession of one or more shared characteristics, which can be based on protein sequence, protein structure, or function. These shared characteristics suggest that the proteins have a common evolutionary origin.

Classification

Protein families are classified based on their shared characteristics. The most common method of classification is based on sequence similarity, which is often determined using bioinformatics tools such as BLAST. Other methods of classification include structural similarity and functional similarity.

Examples

There are many examples of protein families. Some of the most well-known include the G-protein coupled receptor family, the kinase family, and the immunoglobulin family. Each of these families contains proteins that share common features and functions.

Importance

Understanding protein families is crucial for many areas of biology, including genetics, molecular biology, and biochemistry. By studying protein families, scientists can gain insights into protein function, protein structure, and the evolutionary history of proteins.

See also

• Protein structure
• Protein function
• Protein sequence
• Evolution of proteins