Intracranial injections induce local transcription of a gene encoding precerebellin-like protein

Abstract

The gene encoding the precerebellin-like protein, named on the basis of homology with precerebellin that was first discovered in the mammalian cerebellum, had been previously found to be activated in teleost liver tissue in response to elicitors of the acute phase response, and the protein is present in the acute phase plasma of teleosts. Properties of the molecule led us to hypothesize immune-relevant functions in the brain. Experiments reported here reveal that intracranial injections of killed Gram positive or Gram negative bacteria into fully anesthetized rainbow trout induce transcription of precerebellin-like protein in brain tissue. Intraperitoneal injections strongly elicited transcription in the liver and provoked weak transcription in the brain. Gene activation also followed injury due to intracranial injections of either mineral oil or turpentine. The function(s) of this protein remain unknown in any species. Acute phase proteins generally participate in the restoration of homeostasis following either sterile or septic injury. Any such restorative function in the brain should be accompanied by expression following injury. Structural, biological and evolutionary attributes of this gene family reported here are interpreted to signify that its members may be of health relevance in this and other species; the expression patterns and potential functions of precerebellin should be determined in mammalian liver and brain tissues.