Meeting Abstract
Cnidarian genomes provide a framework for exploring fundamental biological processes such as embryonic development, regeneration, self-recognition, and aging. We are focusing on the colonial cnidarian Hydractinia, a hydrozoan representative that has incredible regenerative ability largely due to a lineage of migratory stem cells known as ‘i-cells’. In this system, one can study gene function using several established functional genomics tools, including CRISPR/Cas9 genome editing. We have generated high-quality, high-coverage genome and transcriptome assemblies for H. echinata and its sister species, H. symbiolongicarpus, using PacBio long-read and Dovetail-based strategies for the genome and Illumina data for the transcriptome. The length of the genome assemblies are 419 Mb for H. echinata (84x coverage, 1,582 scaffolds, N50 of 1.51 Mb) and 308 Mb for H. symbiolongicarpus (94x coverage, 392 scaffolds, N50 of 3.31 Mb), placing them among the most contiguous invertebrate genomes. Similar to Hydra, both genomes are AT-rich (65%) and highly repetitive (>50%). We are using a comparative genomics approach that includes ortholog clustering to determine how closely these genomes resemble other established cnidarian model genomes. Our results reveal both the conserved features and extensive evolutionary novelties contained within these Hydractinia genomes.
