Accumulation, biotransformation and time-dependent transcriptomic responses to PSTs in scallop kidneys

Area of Science:

• Marine Biology
• Ecotoxicology
• Molecular Biology

Background:

• Bivalve scallops accumulate paralytic shellfish toxins (PSTs) from toxic algae, posing public health risks.
• The kidney is a primary site for toxin transformation in scallops.

Purpose of the Study:

• Investigate molecular responses in scallop kidneys to PST exposure.
• Analyze time-course transcriptome changes during PST accumulation.
• Identify genes involved in PST biotransformation and detoxification.

Main Methods:

• Time-course transcriptome analysis of Yesso Scallop (Patinopecten yessoensis) over 15 days.
• Exposure to PST-producing algae (Alexandrium catenella).
• Analysis of differentially expressed genes (DEGs) and toxin profiles.

Main Results:

• PST accumulation increased over 15 days, with a shift from low-toxicity C2 to high-toxicity neoSTX and STX.
• DEGs were concentrated on days 3 and 10, correlating with toxin changes.
• The SLC family was consistently upregulated; C-type lectin showed biphasic expression; Calmodulin upregulated on day 15.
• SULT4A1 was identified as a potential key gene in PST biotransformation, significantly associated with neoSTX and STX levels.

Conclusions:

• Scallop kidneys exhibit complex molecular adaptations to PST exposure.
• SULT4A1 plays a crucial role in converting low-toxicity PSTs to high-toxicity derivatives.
• This research provides insights into shellfish defense mechanisms against phycotoxins.