Calreticulin 4, pseudogene (CALR4P)

Calreticulin 4, pseudogene (CALR4P) refers to a **human gene with sequence homology to calreticulin chaperone proteins**, but which is **pseudogenized and non-functional in humans and other primates**—that is, it contains mutations that prevent it from being transcribed into a functional protein[1]. In contrast, in other species such as **mouse and rat**, the orthologous gene (known as calreticulin4) encodes a functional endoplasmic reticulum chaperone highly expressed in vomeronasal sensory neurons (VSNs) and implicated in protein folding and suppression of ER stress via the unfolded protein response. Functional calreticulin4 in these species may contribute to the expression and trafficking of vomeronasal receptor (V2R) proteins by providing chaperone activity in the ER, but **no such functional protein exists in humans**. This gene should not be considered a genuine drug or therapeutic target, nor a receptor, enzyme, transporter, or similar biomolecule in humans[1]. **Notes and Rationale:** - "Calreticulin 4, pseudogene" (CALR4P) in *humans* is **not a protein-coding gene, nor a functional receptor or chaperone**—it is a nonfunctional remnant, also known as a pseudogene[1]. - Functional Calreticulin4 is present primarily in *non-human mammals* with a working vomeronasal organ, and is involved in chaperoning and folding specific olfactory receptors, but these functions are *lost in humans*[1]. - There are no common drugs, disease associations, therapeutic mechanisms, or roles as a biomarker or safety concerns, as this gene does not produce a functional protein in humans. - There is nothing misspelled or ambiguous about the label, but it **is incorrect to consider this a human therapeutic target or receptor**. All data above is directly supported by [1].

Other names

Calreticulin4calreticulin 4CRT4pseudogene CALR4human calreticulin 4 pseudogene