cDNA cloning and characterization of the nuclear gene encoding chloroplast glyceraldehyde-3-phosphate dehydrogenase from the marine red alga Gracilaria verrucosa.
Using a PCR-generated homologous probe, we have recovered a cDNA (GapA cDNA) encoding the complete 338 amino-acid chloroplast GAPDH of the marine red alga Gracilaria verrucosa, together with its 78 amino-acid transit peptide. This cDNA was readily aligned with chloroplast-localized GAPDH genes (GapA and GapB) of green plants. The proline residue which contributes to the specificity of NAD+ binding to cytosolic GAPDHs is absent from the deduced polypeptide chain of G. verrucosa GapA as is also the case in the chloroplast GAPDHs of plants. The transit peptide shows a high proportion of random coil, an amino-terminal Met-Ala dipeptide, a high content of hydroxylamino acids, and a net positive charge. The polyadenylation signal appears to be AGTAAA. Genomic Southern-hybridization data indicate that only one chloroplast-GAPDH gene may occur in G. verrucosa. Bootstrapped parsimony trees indicate that the G. verrucosa GapA gene is a sister group to plant chloroplast-GAPDH genes, and are most readily interpreted as showing that red algal and plant chloroplast-localized GAPDHs arose in a single endosymbiotic event.
Zhou
Y H
YH
Institute for Marine Biosciences, National Research Council of Canada, Halifax, Nova Scotia.
Ragan
M A
MA
D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D002467:Cell Nucleus; D002736:Chloroplasts / Q000201:enzymology*; D003001:Cloning, Molecular; D004247:DNA; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D000461:Rhodophyta / Q000201:enzymology / Q000235:genetics*; D017386:Sequence Homology, Amino Acid
D004247:DNA; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases