Cloning of a Ca(2+)-ATPase gene of Plasmodium falciparum and comparison with vertebrate Ca(2+)-ATPases.
A Ca(2+)-ATPase gene was cloned from the genomic libraries of Plasmodium falciparum. From the deduced amino acid sequence of the gene, a 139 kDa protein with a total of 1228 amino acids was predicted. Sequence of a partial cDNA clone of the gene identified two introns near the 3'-end at the regions identical to the regions assumed for the Ca(2+)-ATPase gene of P. yoelii, a rodent malaria species. As compared with a variety of Ca(2+)-ATPases, the P. falciparum Ca(2+)-ATPase had the highest amino acid sequence homology (78%) to the P. yoelii Ca(2+)-ATPase, moderate homology (45-50%) to vertebrate sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPases (SERCAs), and lowest homology (20%) to a plasma membrane Ca(2+)-ATPase. The P. falciparum protein conserved sequences and residues that are important for the function and/or structure of the organellar type Ca(2+)-ATPase, such as high affinity Ca(2+)-binding sites, fluorescein isothiocyanate (FITC)-binding regions, and the phosphorylation site, but the protein did not contain calmodulin-binding regions that occur in the plasma membrane type Ca(2+)-ATPase. Thus we concluded the cloned gene was the organellar type Ca(2+)-ATPase of P. falciparum. In a region between the phosphorylation site and FITC-binding region, the P. falciparum protein was about 200 residues longer than the rabbit SERCA and lacked a sequence that binds to phospholamban, a protein that regulates the activity of the rabbit SERCA.(ABSTRACT TRUNCATED AT 250 WORDS)
Kimura
M
M
Biophysics Laboratory, Osaka City University Medical School, Japan.
Yamaguchi
Y
Y
Takada
S
S
Tanabe
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D000252:Calcium-Transporting ATPases / Q000235:genetics*; D003001:Cloning, Molecular; D017124:Conserved Sequence; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000201:enzymology / Q000235:genetics*; D017433:Protein Structure, Secondary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D000252:Calcium-Transporting ATPases