Eps15 homology domain-containing protein 3, abbreviated as EHD3 and also known as PAST3, is a protein encoded by the EHD3 gene. It has been observed in humans, mice and rats. It belongs to the EHD protein family, a group of four membrane remodeling proteins related to the Dynamin superfamily of large GTPases. Although the four of them are 70-80% amino acid identical, they all have different locations. Its main function is related to endocytic transport.

The primary structure of a protein is related to which amino acids a protein is made of. EHD3 has 535 amino acids, of which almost three-quarters are common in the four EHD proteins. This protein has a molecular mass of 60887 daltons.

The secondary structure of the EHD3 protein still remains unknown.

The tertiary structure of a protein involves the domains it is formed of. EHD3 protein is formed of four different domains:

Protein post-translational modifications (PTM) increase the functional diversity of the proteome by the covalent addition of functional groups or proteins, by the hydrolysis of peptide bonds that link amino acids together or by the degradation of different parts of the protein. The EHD3 protein suffers three kinds of amino acid modifications:

The EH domain is a common motif in a family of proteins involved in endocytic trafficking. This family of four paralogs (EHD1-EHD4) has been implicated in receptor intracellular trafficking, particularly in internalization and recycling to the plasma membrane. The list of functions of EHD proteins is just starting to be populated.

EHD3 is a moonlighting protein, which means it can perform different functions depending on the tissue where the protein is located. The main functions are the following:

The gene that encodes the human EHD3 protein is located in chromosome number 2, most specifically in the 23.1 region. On the other hand, the murine EHD3 gene is located in chromosome 17, in the 21st region. The human gene is formed approximately of 35,438 bases.