ABSTRACT
Ultracold preservation is widely used for storage of genetic stocks of Caenorhabditis elegans. Current cryopreservation protocols are vulnerable to refrigeration failures, which can result in the loss of stock viability due to damage during re-freezing. Here we present a method for preserving worms in a dehydrated and frozen form that retains viability after multiple freeze/thaw cycles. After dehydration in the presence of trehalose or glycerol, C. elegans stocks can be frozen and thawed multiple times while maintaining viability. Both stress-resistant dauer and non-dauer larvae survive desiccation and freezing. Survival after desiccation is dependent on the forkhead box transcription factor homologue DAF-16. Our technique is useful for storing stocks in a manner robust to freezer failures, and potentially for shipping strains between laboratories.
Competing Interest Statement
The authors have declared no competing interest.