SEQUENCE OF THE NON-PHOSPHORYLATING GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE FROM NICOTIANA-PLUMBAGINIFOLIA AND PHYLOGENETIC ORIGIN OF THE GENE FAMILY

A cDNA-library has been constructed from Nicotiana plumbaginifolia see dlings, and the non-phosphorylating glyceraldehyde-3-phosphate dehydro genase (GapN, EC 1.2.1.9) was isolated by plaque hybridization using t he cDNA from pea as a heterologous probe. The cDNA comprises the entir e GapN coding region. A putative polyadenylation signal is identified. Phylogenetic analysis based on the deduced amino acid sequences revea led that the GapN gene family represents a separate ancient branch wit hin the aldehyde dehydrogenase superfamily. It can be shown that the G apN gene family and other distinct branches of the superfamily have it s phylogenetic origin before the separation of primary life-forms. Thi s further demonstrates that already very early in evolution, a broad d iversification of the aldehyde dehydrogenases led to the formation of the superfamily. (C) 1997 Elsevier Science B.V.