Adiponectin and adiponectin receptor genes are coexpressed during zebrafish embryogenesis and regulated by food deprivation.

Adiponectin is an adipocytokine that plays important roles in glucose and lipid homeostasis. Adiponectin binds to two types of transmembrane receptors: Adiponectin receptor (AdipoR) type 1 and 2. We isolated and characterized the two adiponectin genes (adiponectin A and B) and the three adiponectin receptors in zebrafish. In adult, adiponectin A is only detected in the kidney while adiponectin B mRNAs are widely expressed and are detected in the liver, adipose tissue, muscle, and brain. The receptors are found in many tissues such as the brain, gut, liver, adipose tissue, kidney, and ovary. Interestingly, we detect embryonic synexpression of all genes in the pharyngeal region. We observed that adiponectin B expression in adult liver is reduced while the expression of the receptors is increased in fasted fish. These data indicate that the upstream members of the Adiponectin pathway have complex expression patterns and are regulated by food deprivation in zebrafish.