TM4SF20
Description
The TM4SF20 (transmembrane 4 L six family member 20) is a protein-coding gene located on chromosome 2.
TM4SF20 is a polytopic transmembrane protein that plays a role in regulating collagen synthesis by inhibiting the activation of CREB3L1, a transcription factor involved in collagen production. This inhibition is achieved by blocking the regulated intramembrane proteolysis (RIP) of CREB3L1. However, in the presence of ceramide, TM4SF20's membrane topology changes, leading to the stimulation of RIP activation of CREB3L1. Ceramide also triggers a process called "regulated alternative translocation" (RAT), which reverses the direction of transmembrane helices during the translation of TM4SF20 into the endoplasmic reticulum membrane. This mechanism ultimately influences the function of TM4SF20.
TM4SF20 is also known as PRO994, SLI5, TCCE518.