Sequencing, assembly, and annotation of Hydra oligactis and strain AEP Hydra vulgaris genomes

The epithelial and interstitial stem cells of the freshwater polyp Hydra are the best characterized stem cell systems in any cnidarian, providing valuable insight into cell type evolution and the origin of stemness in animals. However, little is known about the transcriptional regulatory mechanisms that determine how these stem cells are maintained and how they give rise to their diverse differentiated progeny. To address such questions, a thorough understanding of transcriptional regulation in Hydra is needed. To this end, we report two new high-quality genomes, a chromosome-level assembly for the AEP strain of H. vulgaris and a draft assembly for the H. oligactis Innsbruck female12 strain. To accompany the new H. vulgaris assembly, we also generated genome-wide maps of chromatin interactions, chromatin accessibility, sequence conservation, and histone modifications.