Search bioRxiv⌕ Search

Biology subjects

Vernadou, E.

Publications and source records attributed to Vernadou, E..

3 recordsLinked to original sources

ERGA-BGE genome of Noah's Ark shell (Arca noae Linnaeus, 1758), a Mediterranean bivalve species

Arca noae, also known as the Noahs Ark clam, is a bivalve mollusk found in the shallow coastal waters of the Mediterranean Sea and the eastern Atlantic Ocean. This species plays a crucial ecological role by filtering plankton and organic particles from the water, helping maintain water quality and supporting nutrient cycling in marine ecosystems. It is also an important food source for various marine predators, including fish and crustaceans, thereby contributing to the coastal food web. Arca noae is notably resilient to environmental stressors, such as temperature fluctuations, changes in salinity, and pollution, making it a valuable model species for studying how bivalves adapt and respond to stress. While it is not commonly harvested commercially, Arca noae is of great interest to marine researchers due to its ability to thrive in diverse coastal habitats. The reference genome of Arca noae will thus provide important evolutionary insights. The entirety of the genome sequence was assembled into 19 contiguous chromosomal pseudomolecules. This chromosome-level assembly encompasses 1.5 Gb, composed of 257 contigs and 119 scaffolds, with contig and scaffold N50 values of 20.5 Mb and 84.7 Mb, respectively.

genomics↗

ERGA-BGE genome of Pinctada radiata (Leach, 1814): one of the first Lessepsian migrants

Pinctada radiata, commonly known as the Gulf pearl oyster, is a species of pearl oyster found primarily in the warm waters of the Red Sea, the Persian Gulf, and parts of the Indian Ocean. Pinctada radiata contributes to marine ecosystems by filtering water, which helps maintain water quality and supports other marine life. This species is the first bivalve Lessepsian migrant, having migrated from the Red Sea to the Mediterranean Sea via the Suez Canal. The reference genome of Pinctada radiata could help identify genes enabling adaptation to varying temperatures and salinities, facilitating survival in diverse and newly colonized habitats allowing comparisons with other bivalves to uncover shared and unique genetic adaptations. Additionally, the genome could support targeted management practices and conservation initiatives, such as habitat restoration and selective breeding, ensuring the long-term sustainability of P. radiata. The entirety of the genome sequence was assembled into 14 contiguous chromosomal pseudomolecules. This chromosome-level assembly encompasses 0.93 Gb, composed of 220 contigs and 44 scaffolds, with contig and scaffold N50 values of 8.1 Mb and 63.8 Mb, respectively.

genomics↗

A long-term ecological research data set from the marine genetic monitoring programme ARMS-MBON 2018-2020

Molecular methods such as DNA/eDNA metabarcoding have emerged as useful tools to document biodiversity of complex communities over large spatio-temporal scales. We established an international Marine Biodiversity Observation Network (ARMS-MBON) combining standardised sampling using autonomous reef monitoring structures (ARMS) with metabarcoding for genetic monitoring of marine hard-bottom benthic communities. Here, we present the data of our first sampling campaign comprising 56 ARMS units deployed in 2018-2019 and retrieved in 2018-2020 across 15 observatories along the coasts of Europe and adjacent regions. We describe the open-access data set (image, genetic, and metadata) and explore the genetic data to show its potential for marine biodiversity monitoring and ecological research. Our analysis shows that ARMS recovered more than 60 eukaryotic phyla capturing diversity of up to [~]5,500 amplicon sequence variants and [~]1,800 operational taxonomic units, and up to [~]250 and [~]50 species per observatory using the cytochrome c oxidase subunit I (COI) and 18S rRNA marker genes, respectively. Further, ARMS detected threatened, vulnerable and non-indigenous species often targeted in biological monitoring. We show that while deployment duration does not drive diversity estimates, sampling effort and sequencing depth across observatories do. We recommend that ARMS should be deployed for at least three to six months during the main growth season to use resources as efficiently as possible and that post-sequencing curation is applied to enable statistical comparison of spatio-temporal entities. We suggest that ARMS should be used in biological monitoring programmes and long-term ecological research and encourage the adoption of our ARMS-MBON protocols.

ecology↗