RNF

RNF is an acronym used in biology to denote a family of proteins known as ring finger proteins. The defining feature of these proteins is the presence of a RING finger domain, a cysteine-rich motif that coordinates zinc ions. The RING domain supports E3 ubiquitin ligase activity, allowing RNF proteins to catalyze the transfer of ubiquitin from an E2 enzyme to substrate proteins. Through this activity, RNF proteins regulate protein stability, activity, or localization and participate in various cellular pathways.

The RNF family is large and diverse, with many genes named RNF followed by a number (for example, RNF8, RNF168, RNF20, RNF40, RNF4). Members vary in localization, substrates, and biological roles, and they participate in processes such as DNA damage response, cell cycle control, transcription, and signaling. Notable examples include RNF8 and RNF168, which promote ubiquitin signaling at sites of DNA double-strand breaks, and the RNF20/40 complex, which ubiquitylates histone H2B to influence chromatin structure. RNF4 acts as a SUMO-targeted ubiquitin ligase that recognizes SUMO-modified proteins and targets them for ubiquitination.

Dysregulation or mutation of RNF genes has been linked to diseases including cancer and neurodegenerative disorders, and RNF proteins are active areas of biomedical research as potential therapeutic targets. Research continues to map substrates and regulatory networks for RNF proteins to better understand their roles in health and disease.