Peptidoglycan Recognition Protein 4 (PGLYRP4)

PGLYRP4 contains an N-terminal signal peptide, followed by a transmembrane segment, PGRP domains IV, III, and II, a second transmembrane segment, and PGRP domain I at the extracellular C terminus. PGRPI-beta shares 32%, 42%, and 68% identity with PGRPL), PGRPS, and PGRPI-alpha (PGLYRP3), respectively. PGRP domain IV in PGRPI-beta is 96% identical to PGRP domain IV in PGRPI-alpha. RNA dot blot analysis detected weak PGRPI-beta expression only in esophagus. Northern blot analysis detected a 2.6-kb transcript in esophagus, and PCR detected expression in esophagus, tonsils, and thymus. Transiently transfected COS-7 and human embryonic kidney cells expressed PGRPI-beta as a Triton X-100-soluble membrane protein with an apparent molecular mass of 46 kD.