Project Summary The objective of the Caenorhabditis Genetics Center (CGC) Resource Component is to promote research on the small metazoan Caenorhabditis elegans by curating important, genetically characterized nematode stocks and distributing them upon request to researchers and science educators. The CGC is the sole general stock center for the curation and distribution of C. elegans. The CGC currently houses nearly 23,000 different strains, and they are immensely popular: ~30,000 strains are distributed each year and the majority goes to >3,400 user groups in the United States. Researchers in all locales supply us with important strains that they have generated. If the CGC were not performing this curation and distribution service, strain sharing would be extremely inefficient and costly; the burden of filling requests would be placed upon individual labs. Moreover, the conservation of many published strains might be in jeopardy. This would be a great loss, because research in this model organism has led to fundamental insights into basic biological mechanisms, including programmed cell death, the discovery of microRNAs, and the mechanism of RNA interference in animals. C. elegans has also provided insights to mechanisms of cancer progression and other diseases including Alzheimer's and Parkinson's. In addition to enhancing research progress, the CGC offers major cost-savings to the NIH as a whole, to individual research labs funded by NIH, and to all other labs in the community, through decreasing redundant labor by making new mutations and mutant combinations readily available. An economy- of-scale strain distribution approach decreases labor and other costs by relieving individual labs of the responsibility for disseminating useful strains, and it safeguards strains made with NIH grant support through curation in redundant sites. The CGC facilitates use of this relatively low-cost model by investigators working primarily in high-cost models such as mice. The continued constant growth of the Center has necessitated purchase of additional equipment to support long-term storage and preservation of our growing strain collection and for enabling work with the rapidly increasing numbers of fluorescently marked strains in the collection.