Recently, the innovation team of the Chinese Academy of Fishery Sciences and the”innovation team of aquatic animal breeding with Yangtze River characteristics” of the freshwater fishery research center have made new progress in the research of freshwater snail genetics and seedling breeding.
Pear shaped ring ribbed snail (B. purificata), commonly known as snail, stone snail, bean field snail and lake snail, is the largest individual species in the ring ribbed snail genus. It has the advantages of wide distribution and multiple uses. It is not only an important natural bait for high-quality aquatic products such as Chinese mitten crab, Chinese turtle and herring, but also the only bait source for the characteristic aquatic product wide bodied leech, and is also an important part of the”vegetable basket” project of the general public. As one of the important raw materials of Liuzhou snail powder, the shortage of pear shaped ring ribbed snails has also limited the rapid development of local characteristic industries to a certain extent. In addition, in the freshwater ecosystem, pear shaped ring ribbed snails also play an irreplaceable role in maintaining the balance of freshwater ecosystem.
Since 2015, the team has carried out a series of studies on the population genetics, selective breeding, non feeding culture in the primary purification area of the pond and”rice snail co cultivation” and aquatic product processing, and accumulated a series of solutions for the large-scale breeding of pear shaped ring snail.
In order to further tap the germplasm resources of piriformis, the team obtained the first chromosome level genome of piriformis through pacbio sequencing and Hi-C technology assembly, resulting in a total of 33.64gb circular consistent sequences. The genome size of the preliminarily assembled pear shaped ring ribbed snail is 1.01gb, CoNtig N50 is 45.14mb long. Through the error correction of Hi-C technology, the 984.33mb pear shaped ring ribbed snail genome, CoNtig N50 is 37.21mb long and scaffold N50 is 141.97 MB long. 99.28%of the genome sequence is anchored to 8 chromosomes, and a total of 22125 protein coding genes are predicted. Phylogenetic analysis showed that pear shaped ring edge snail and longevity snail differentiated about 288million years ago; Comparative genomic analysis showed that 34 gene families expanded, 26 gene families contracted, and 4 protein encoded genes were positively selected (fdr< 0.05). This study provides important genomic resources for further exploring the ecology, evolution and selective breeding of freshwater snails.
The relevant research paper”chromosome level genome assembly of the freshwater snail Bellamya purificata (caenogastropoda)” was published online in the journal zoological research (if=6.975) in the first district of JCR. Dr. Jin Wu from the aquaculture research office of Danshui center and associate professor caoxiaojuan from the Fisheries College of Huazhong Agricultural University are the co first authors, and researchers Xu Dongpo and Wen Haibo are the co corresponding authors. Full text website:https://www.zoores.ac.cn/en/article/doi/10.24272/j.issn.2095-8137.2022.118
This research was supported by the basic scientific research business fee of the Academy of Water Sciences (2021xt703) and the basic business fee of the freshwater Center (2021jbfm07).
(contributed by the Yangtze River characteristic aquatic animal breeding innovation team, aquaculture research office and aquatic biological resources research office of the Institute)