THE NUCLEAR GENE AND CDNAS ENCODING CYTOSOLIC GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE FROM THE MARINE RED ALGA GRACILARIA-VERRUCOSA - CLONING, CHARACTERIZATION AND PHYLOGENETIC ANALYSIS

We have cloned and sequenced the single-copy nuclear gene (GapC) encod ing the complete 335-amino acid cytosolic glyceraldehyde-3-phosphate d ehydrogenase (GAPC) from the red alga Gracilaria verrucosa. The prolin e residue which contributes to the specificity of NAD(+) binding in ot her GAPC-like proteins is present. Putative regulatory regions, includ ing GC-rich regions, a GATA element, and 11-base T- and T/G-clusters, but excluding TATA- and CCAAT-boxes, were identified upstream. Two typ es of GapC cDNAs differing in polyadenylation site were characterized. An 80-bp phase-two spliceosomal intron was identified in a novel posi tion interrupting the highly conserved cofactor-coding region I. The G . verrucosa GAPC was easily aligned with other known GAPC-type sequenc es. Inferred phylogenetic trees place red algae among the eukaryote cr own taxa, although with modest bootstrap support and without stable re solution among related GAPC lineages.