Project description:Protists are pivotal components of marine ecosystems in terms of their high diversity, but protist communities have been poorly explored in benthic environments. Here, we investigated protist diversity and community assembly in surface sediments in the South China Sea (SCS) at a basin scale. Pyrosequencing of 18S rDNA was performed for a total of six samples taken from the surface seafloor at water depths ranging from 79 to 2,939 m. We found that Cercozoa was the dominant group, accounting for an average of 39.9% and 25.3% of the reads and operational taxonomic units (OTUs), respectively. The Cercozoa taxa were highly diverse, comprising 14 phylogenetic clades, six of which were affiliated with unknown groups belonging to Filosa and Endomyxa. Fungi were also an important group in both read- (18.1% on average) and OTU-derived (9.3% on average) results. Moreover, the turnover patterns of the protist communities were differently explained by species sorting (53.3%), dispersal limitation (33.3%), mass effects (0%), and drift (13.3%). In summary, our findings show that the basin-wide protist communities in the surface sediments of the SCS are primarily dominated by Cercozoa and are mainly assembled by species sorting and dispersal limitation.
Project description:The present study identified and characterized miRNAs, which may play a major role in stress resistance. we applied high-throughput sequencing to investigate the alterations of miRNAs expression of sea cucumber under hypoxia stress(DO2_1,DO2_2,DO2_3),slight hypoxia stress(DO4_1,DO4_2,DO4_3) and normal condition(DO8_1,DO8_2,DO8_3). These results will provide a basis for future studies of miRNA regulation in sea cucumbers under hypoxia stress.
