Cloning and expression analysis of putative glyceraldehyde-3- phosphate dehydrogenase genes in Pilobolus crystallinus

Putative glyceraldehyde-3-phosphate dehydrogenase (gapdh) genes were cloned from Pilobolus crystallinus with degenerated primers designed from conserved sequences in many GAPDHs. P. crystallinus had three gapdh homologue genes, named pcgapdh1, pcgapdh2, and pcgapdh3. Deduced amino acid sequences for PCGAPDH1, PCGAPDH2, and PCGAPDH3 showed highest similarity with GPD3, GPD1, and GPD2, respectively, of Mucor circinelloides, indicating that these three gapdh genes had diverged before Pilobolus and Mucor were separated. The expression patterns of the gapdh genes, however, were quite different between P. crystallinus and M. circinelloides. All the three pcgapdh genes were expressed, and the expression of pcgapdh2 was suppressed by glucose and sodium acetate. These results indicate that the function of these orthologous genes was changed after Pilobolus and Mucor were separated.