C. elegans Cold Tolerance Model Service

Environmental temperature is critical for the survival and proliferation of animals, which directly affects biochemical processes in organisms. Therefore, the acclimation of temperature is essential for animal survival. A range of mechanisms are adapted to cope with environmental temperature changes. However, thermoregulation mechanisms remain poorly understood. In addition, the research of thermotaxis in C. elegans has been studied extensively for several decades, while cold tolerance is a relatively recent concept in C. elegans. Although both of them require temperature sensation, C. elegans uses the proper mechanisms depending on its situation, and displays them in different responsible neurons and molecular pathways. Here we provide C. elegans cold tolerance model service to assist customers to investigate mechanisms of temperature habituation, and also provide access to customers to acquire a surrogate screen for broader neuronal dysfunction.

Cold tolerance in C. elegans

It is known that the nematode Caenorhabditis elegans exhibit cold tolerance in response to environmental temperature decrease. For instance, wild-type animals raised in cooler temperatures at 15°C are able to survive a sudden shift to a cold temperature at 2°C for 48 h. Whereas those raised at warmer temperatures at 20-25°C die following a similar sudden cold stress. This cultivation-temperature-dependent cold tolerance is termed cold acclimation and can occur after a few hours of exposure to a changed cultivation temperature in C. elegans. Therefore, the cold acclimation of C. elegans is thought to involve fundamental mechanisms of plasticity in metabolic systems and/or memory dynamism in temperature responses. For example, the laboratory strain, N2, cultured at 25°C do not survive at 2°C, and those cultured at 15°C do. However, when animals cultured at 25°C are transferred to 15°C for a certain time, they are able to survive at 2°C. C. elegans has cold tolerance ability and displays changes in physiology. Studies demonstrated that in order to preserve cell membrane fluidity at low temperatures, the worms increase the total proportion of unsaturated fatty acids. Therefore, cold tolerance assays can potentially help identify important mechanisms that regulate cold adaptation, including lipid homeostasis.

Furthermore, previous research reported that ASJ sensory neurons detect temperature, and control cold-tolerance through insulin signaling. The ASJ sensory neuron contains ASJL and ASJR, a single pair of neurons, which are located in the head and are required for sensing warm temperature. Active ASJ neurons initiate a signaling cascade that results in cold-induced lipid modulation in the gut and decreased cold tolerance. In the absence of signaling from the ASJ nerve pair, worms maintain a cold-resistant lipid profile. Therefore, it makes a rapid and robust method to detect changes in signaling from these neurons when testing C. elegans ability to survive a sudden shift to a cold temperature, and may provide a surrogate screen for broader neuronal dysfunction.

A feedback network in cold tolerance of Caenorhabditis elegans. (Sonoda S, et al, 2016)

Cold tolerance model in CD BioSciences

C. elegans cold tolerance assays involve synchronized L4 larval stage or young adult worms are exposed at specific temperatures ranging from 0°C to 4°C. Notably, temperatures below 0°C should be avoided because worms are unable to survive at such low temperatures. Here we provide two cold tolerance model services using C. elegans, including a standard cold-tolerance assay after cultivation at a constant temperature, and a multistep temperature-shifted cold-tolerance assay, to meet the needs of customers.

C. elegans is a simple model and has been used in the study of temperature behaviors and tolerance. Cold sensitivity is broadly applicable for rapidly identifying neuronal function under specific genetic or transgenic backgrounds, as well as for the larger scale forward and reverse genetic screening. CD BioSciences provides C. elegans cold tolerance model service to help customers get insight to the mechanisms of cold adaptation, and also offers a surrogate screen for broader neuronal dysfunction. If you are interested in this area, please don't hesitate to contact us.

References

1. Ujisawa T, et al.( 2018). “Endoribonuclease ENDU-2 regulates multiple traits including cold tolerance via cell autonomous and nonautonomous controls in Caenorhabditis elegans”. Proc Natl Acad Sci U S A.115(35):8823-8828.
2. Sonoda S, et al. (2016). "Sperm Affects Head Sensory Neuron in Temperature Tolerance of Caenorhabditis elegans." Cell Rep. 16(1):56-65.

* For research use only.