Nomenclature
The nomenclature of arrestin protein and gene is very confusing. In fact, the nomenclature of arrestin should be as follows: arrestin-1 (historic names S-antigen, 48 kDa protein, visual or rod arrestin), arrestin-2 (β-arrestin or β-arrestin1), arrestin-3 (β-arrestin2 or hTHY-ARRX), and arrestin-4 (cone or X-arrestin; for unclear reasons its gene is called “arrestin 3” in the HUGO database)(Zhan, Perez, Gimenez, Vishnivetskiy, & Gurevich, 2014). We would like to useARR4 (OMIM: 301770) to avoid the confusion of nomenclature, because this can be referred back to numerous previous research results, so as to have continuity in research outputs of this field.