Cryopreservation of Platynereis dumerilii larvae

Area of Science:

• Marine Biology
• Developmental Biology
• Cryobiology

Background:

• Platynereis dumerilii is a key model organism in various biological studies.
• Increasing research necessitates efficient methods for maintaining genetic variants.
• Live culture maintenance poses a significant burden on researchers.

Purpose of the Study:

• To develop and validate the first cryopreservation protocol for Platynereis dumerilii larvae.
• To establish a method for long-term storage and propagation of P. dumerilii genetic lines.
• To reduce the challenges associated with maintaining live cultures of this model organism.

Main Methods:

• Larvae (6-8 days post-fertilization) were equilibrated with cryoprotectants (5% Me2SO + 0.1% sucrose) for 1 hour.
• Samples were cooled at 2.5°C/min to -35°C using a programmable freezer, then plunged into liquid nitrogen.
• Thawing was performed in a 18°C water bath, followed by a specific feeding regime (Tetraselmis and diatoms).

Main Results:

• The protocol achieved up to 34% survival after approximately 5 months.
• Average survival rate was 8.69% at 140 days post-thaw, with significant inter-batch variability.
• Cryopreserved larvae successfully developed into adults and reproduced.

Conclusions:

• This cryopreservation protocol offers a viable solution for maintaining Platynereis dumerilii stocks.
• The method alleviates the burden of continuous live culture maintenance.
• Further optimization may reduce variability and improve overall survival rates.