The barnacles are a group of more than 2,000 species that have fascinated biologists, including Darwin, for centuries. Their lifestyles are extremely diverse from free-swimming larvae to sessile adults, and even root-like endoparasites. Barnacles also have a major economic impact with hundreds of millions of dollars of losses annually due to biofouling. Genomic resources for crustaceans, and barnacles in particular, are lacking. Using 62x PacBio coverage, 189x Illumina WGS coverage, 203x HiC coverage, and 69x CHi-C coverage, we produced a chromosome-level genome assembly of the gooseneck barnacle Pollicipes pollicipes. The P. pollicipes genome is 770 Mbp long and its assembly is one of the most contiguous and complete crustacean genomes available, with a scaffold N50 of 47 Mbp and 90.5% of the BUSCO Arthropoda gene set. Using the genome annotation produced here along with transcriptomes of 13 other barnacle species, we completed phylogenetic analyses on a nearly 2 million amino acid alignment.
Contrary to previous studies, our phylogenies suggest the Pollicipedomorpha is sister to the Balanomorpha, which alters our understanding of barnacle larval evolution. We also compared transcriptomes of P. pollicipes nauplius larvae and adults and found that nearly one half of the genes in the genome are differentially expressed. Annotation of the genes with KEGG and GO terms reveals these stages exhibit many differences including cuticle binding, chitin binding, microtubule motor activity, and membrane adhesion.
This study provides high quality genomic resources for a key group of crustaceans. This is especially valuable given the roles P. pollicipesplays in European fisheries, as a sentinel species for coastal ecosystems, and as a model for studying barnacle adhesion as well as its key position in the barnacle tree of life. A combination of genomic, phylogenetic, and transcriptomic analyses here provides valuable insights into the evolution and development of barnacles.

Keywords:

• barnacle
• genome
• assembly
• pollicipes
• pollicipedomorpha

Read the peer-reviewed publication(s):

(PubMed: 35277961)

Additional information:

https://www.ncbi.nlm.nih.gov/genome/annotation_euk/Pollicipes_pollicipes/100/

https://www.ncbi.nlm.nih.gov/assembly/GCF_011947565.2

Accessions (data generated as part of this study):

BioProject: PRJNA614970
BioProject: PRJNA649812
BioProject: PRJNA533106

Projects: