Genetic analysis of metabolic cooperation in mammalian cell lines

Metabolites can be exchanged between cells in culture by direct transfer from the cytoplasm of one cell to that of another in a process known as metabolic cooperation. Most mammalian cell lines are able to transfer small molecules directly between adjacent cells in this way and are consequently mec+; however, a small number are defective in this ability (mec-). Results obtained from somatic cell hybrids formed between combinations of these cells have shown that the four different cell lines examined in this study can be divided into at least two different complementation groups on the basis of their ability to transfer 3H-labeled nucleotides to adjacent cells. Two of the cell lines clearly fall into a single complementation group.