Identification of genes showing differential expression in anorexia mutant mouse

Differential display (DD) PCR was applied to identify genes regulated by anorexia (anx) in mouse brain. Of the four apparently differentially expressed genes, three (H2-H4) had high homology with known genes such as apoptotic protease activating factor 1 (Apaf 1), adenylate cyclase 6 (Adcy 6), and myelin proteolipid protein (PLP). H1, designated as HIPA1, had a homology with unknown function gene fragments. Northern blot analysis confirmed HIPA1 expression induced by anorexia. A 1579 bp full-length cDNA of HIPA1 was isolated from a mouse brain cDNA library using a probe from the differentially displayed H1 fragment. Sequence analysis showed that HIPA1 had 98.7% homology to mouse hippocampus cDNA. In situ hybridization demonstrated that the HIPA1 mRNA was highly up-regulated in the hippocampus of anx/anx mouse brain.