Aspartic proteinase. Expressed in intestinal cells. Induced in response to thermal stress in conditions where severe cold temperatures are followed by warmer temperatures (PubMed:29664006). In particular, induced in the warming phase (10 to 22 degrees Celsius) during the cold (4 degrees Celsius) to warm (22 degrees Celsius) temperature transition (PubMed:29664006). Belongs to the peptidase A1 family.