SEQUENCE AND EXPRESSION OF A GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE-ENCODING GENE FROM QUAIL EMBRYO FIBROBLASTS

Using differential hybridization techniques, a cDNA library derived fr om a line of v-myc-transformed quail embryo fibroblasts was screened f or clones whose expression was elevated in transformed, as compared wi th normal, cells. One of the isolated clones contained the entire codi ng region of the quail glyceraldehyde-3-phosphate dehydrogenase-encodi ng gene (GAPDH). A comparison of the deduced 333-amino-acid (aa) seque nce of quail GAPDH with that of the only other avian (chicken) GAPDH s equence known, and with those of mammalian counterparts indicates the strong aa sequence conservation of this glycolytic enzyme. GAPDH is ex pressed in all transformed and non-transformed quail and chicken embry o fibroblasts and macrophages tested, with a moderate elevation of exp ression in most of the transformed cell lines. In the avian genomes, G APDH is present in a single copy, in contrast to the high number of GA PDH-related sequences in mammalian species.