PLPPR4 and psychiatric disorder: Because PRG‐1 regulates LPA levels and LPA has been demonstrated to cause symptoms related to neurological/psychiatric diseases, the authors used in vitro and in vivo inhibitors of LPA‐synthesizing enzyme autotaxin to decrease extracellular LPA levels and prevent biochemical, electrophysiological and behavioral alterations caused by R346T mutation/monoallelic depletion of the PRG‐1 gene in mice.