Mex-3 homolog D, also known as MEX3D, is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 that in humans is encoded by the MEX3D gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

.

Function

MEX3D is an RNA binding protein that interacts with AU-rich element

AU-rich element

AU-rich elements are one of the most common types of regulatory elements found in mRNAs. They are involved in the control of gene expression. They are the most common determinant of RNA stability in mammalian cells....

s of Bcl-2

Bcl-2

Bcl-2 is the founding member of the Bcl-2 family of apoptosis regulator proteins encoded by the BCL2 gene. Bcl-2 derives its name from B-cell lymphoma 2, as it is the second member of a range of proteins initially described in chromosomal translocations involving chromosomes 14 and 18 in...

. Upon binding, MEX3D has a negative regulatory action on Bcl-2 expression at the posttranscriptional level.

Structure

MEX3 proteins contain two N-terminal heterogeneous nuclear ribonucleoprotein K homology motifs ( KH domain

KH domain

The K Homology domain is a protein domain that was first identified in the human heterogeneous nuclear ribonucleoprotein K. An evolutionarily conserved sequence of around 70 amino acids, the KH domain is present in a wide variety of nucleic acid-binding proteins. The KH domain binds RNA, and can...

 ) and a RING domain at the C-terminus.