HEN-1, a secretory protein with an LDL receptor motif, regulates sensory integration and learning in Caenorhabditis elegans.

Animals sense many environmental stimuli simultaneously and integrate various sensory signals within the nervous system both to generate proper behavioral responses and also to form relevant memories. HEN-1, a secretory protein with an LDL receptor motif, regulates such processes in Caenorhabditis elegans. The hen-1 mutants show defects in the integration of two sensory signals and in behavioral plasticity by paired stimuli, although their sensation capability seems to be identical to that of the wild-type. The HEN-1 protein is expressed in two pairs of neurons, but expression in other neurons is sufficient for wild-type behavior. In addition, expression of HEN-1 at the adult stage is sufficient. Thus, HEN-1 regulates sensory processing non-cell-autonomously in the mature neuronal circuit.