AUTHOR=Kong Lingling , Liu Pingping , Li Moli , Wang Huizhen , Shi Jiaoxia , Hu Jingjie , Li Yueru , Hu Xiaoli 

TITLE=Transcriptional Responses of Flavin-Containing Monooxygenase Genes in Scallops Exposed to PST-Producing Dinoflagellates Implying Their Involvements in Detoxification

JOURNAL=Frontiers in Marine Science

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2021.732000

DOI=10.3389/fmars.2021.732000

ISSN=2296-7745

ABSTRACT=<p>Flavin-containing monooxygenase (FMO) is one of the most prominent xenobiotic metabolic enzymes. It can catalyze the conversion of heteroatom-containing chemicals to polar, readily excretable metabolites and is considered an efficient detoxification system for xenobiotics. Bivalves can accumulate paralytic shellfish toxins (PSTs) produced by dinoflagellates, especially during outbreaks of harmful algal blooms. Exploring <italic>FMO</italic> genes in bivalves may contribute to a better understanding of the adaptation of these species and the mechanisms of PSTs bioavailability. Therefore, through genome screening, we examined the expansion of <italic>FMO</italic> genes in two scallops (<italic>Patinopecten yessoensis</italic> and <italic>Chlamys farreri</italic>) and found a new subfamily (FMO_like). Our expression analyses revealed that, in both scallops, members of the FMO_N-oxide and FMO_like subfamilies were mainly expressed from the D-stage larvae to juveniles, whereas the FMO_GS-OX subfamily genes were mainly expressed at and prior to the trochophore stage. In adult organs, higher expressions of <italic>FMO</italic>s were observed in the kidney and hepatopancreas than in other organs. After exposure to PST-producing algae, expression changes in <italic>FMO</italic>s occurred in hepatopancreas and kidney of both scallops, with more members being up-regulated in hepatopancreas than in kidney for <italic>Alexandrium catenella</italic> exposure, while more up-regulated <italic>FMO</italic>s were found in kidney than in hepatopancreas of <italic>C. farreri</italic> exposed to <italic>A. minutum</italic>. Our findings suggest the adaptive functional diversity of scallop <italic>FMO</italic> genes in coping with the toxicity of PST-producing algae.</p>