ICMT

ICMT (Isoprenylcysteine carboxyl methyltransferase) is an enzyme involved in complex post-translational modification processes and plays a key role in the post-translational regulation of prenylated proteins. ICMT primarily catalyzes the methylation of post-translationally isoprene-methylated C-terminal cysteine residues and targets these proteins to the cell membrane. This modification provides the substrate protein with a hydrophobic uncharged C terminus, thereby enhancing interaction with biological membranes and/or altering the ability to interact with protein partners. ICMT-catalyzed protein prenylation may play a role in cancer. Examples include ICMT-modified RHO GTPases or Ras family members. When the ICMT gene is knocked out, it can inhibit KRAS-induced embryonic fibroblast transformation and inhibit RAS-driven tumorigenesis; or ICMT inhibition can hinder RHO GTPase-related cancer cell invasiveness and metastasis^[1][2].