Cryogenic storage of C. elegans stocks for molecular genetic research

长期低温贮藏设施是我们的秀丽隐杆线虫菌种、大量的化石、cosmids、秀丽隐杆线虫ORFeome文库和有效完整的秀丽隐杆线虫RNAi文库的短期和长期贮藏的重要资源。秀丽隐杆线虫可以保存多年（至少30年），并可以恢复用于进一步分析，这是秀丽隐杆线虫被广泛用于重要生物医学研究项目和重大生物学发现的关键原因。此外，冷冻菌株不进行DNA复制，从而降低了积累不必要突变的可能性，而当菌株在培养皿上长时间保存时可能发生这种情况。三个申请人产生和储存的菌株数量约为13,000株，并不断产生新的菌株。自20世纪70年代初，秀丽隐杆线虫被确定为一种模式生物以来，已经建立了大量的菌株收集，这对申请人以及加拿大和国外的秀丽隐杆线虫研究人员来说，本身就是研究和发现的宝贵资源。如果没有足够的低温储存，维持这些菌株将是昂贵的、可怕的和危险的，因为许多珍贵的菌株可能会丢失。我们三个研究小组共同申请资金，购买一台超低温冰箱和两个液氮储存罐，以取代我们的超低温冰箱，这些超低温冰箱已接近预期寿命的终点，并储存新产生的秀丽隐杆线虫菌株和成千上万的分子DNA结构。目前所有三个实验室的低温储存设施都已接近其容量，此外，如果没有储存设施来转移菌株，失去超低温冷冻机将导致多年积累的大量宝贵菌株的损失。

Long term cryogenic storage facilities are an essential resource for short term and long term storage of our C. elegans strains, large collection of fosmids, cosmids, a C. elegans ORFeome library, and an effectively complete C. elegans RNAi library. C. elegans can be stored for many years (at least 30 years) and recovered for further analysis, which has been a key reason why C. elegans has been widely used in important biomedical research projects and major biological discoveries. In addition, frozen strains do not undergo DNA replication thereby lowering a probability of accumulating unwanted mutations as can happen when strains are maintained for long periods on plates. The number of strains generated and stored by the three applicants is on the order of 13,000 with new strains being generated continuously. The large collection of strains, which has been established since the nematode C. elegans was identified as a model organism in the early 1970s, by itself represents a precious resource for research and discovery for the applicants, as well as C. elegans researchers in Canada and abroad. Maintaining these strains without adequate cryogenic storage would be expensive, formidable, and risky since many precious strains could be lost. We three research groups together request funds for an ultra-low temperature refrigerator and two liquid Nitrogen storage tanks to replace our ultra-low temperature refrigerators, which are approaching the end of their expected life-spans, and to store newly generated C. elegans strains and many thousands of molecular DNA constructs. The current cryogenic storage facilities for all three laboratories are filled close to their capacities and in addition, the loss of an ultra-low temperature freezer without a storage facility to move strains to would result in the loss of a large number of valuable strains accumulated over many years.