MICRONUCLEAR AND MACRONUCLEAR SEQUENCES OF A EUPLOTES-CRASSUS GENE ENCODING A PUTATIVE NUCLEAR-PROTEIN KINASE

The sequences of a 1.8-kbp macronuclear DNA molecule (V3), and the maj ority of its micronuclear counterpart, are reported. The macronuclear V3 DNA molecule contains an open reading frame that is interrupted by a single intron, while the micronuclear copy is interrupted by four in ternal eliminated sequences, one of which is located within the intron . The predicted protein product of the macronuclear V3 gene is a 471-a mino acid polypeptide that is very similar to a group of protein-serin e/threonine kinases from both plant and animal species, some of whose members appear to be involved in cell cycle or growth control.