A classification system for zebrafish adipose tissues

The zebrafish model system offers significant utility for in vivo imaging of adipose tissue (AT) dynamics, and screening to identify chemical and genetic modifiers of adiposity. In particular, AT can be accurately quantified in live zebrafish using fluorescent lipophilic dyes (FLDs). Although, this methodology offers considerable promise, the comprehensive identification and classification of zebrafish ATs has not been performed. Here we utilize FLDs and in vivo imaging to systematically identify, classify and quantify the zebrafish AT pool. We identify 34 regionally distinct zebrafish ATs, including 5 visceral ATs (VATs) and 22 subcutaneous ATs (SATs). For each of these ATs we describe detailed morphological characteristics to aid their identification in future studies. Further, we quantify the areas for each AT, and construct regression models to allow prediction of expected AT size and variation across a range of developmental stages. Finally, we demonstrate the utility of this resource for identifying effects of strain variation and high-fat diet on AT growth. Together, this resource provides foundational information on the identity, dynamics, and expected quantities of zebrafish ATs for use as a reference for future studies. Disease Models & Mechanisms • DMM • Advance article