Characterisation of the Cdc2-related kinase 2 gene from Plasmodium knowlesi and P. berghei.
The complete sequence of the cdc2-related kinase 2 (CRK2) gene from Plasmodium knowlesi and from P. berghei was determined. In both species, the CRK2 gene is closely linked to an elongation factor 1 alpha gene. The two CRK2 proteins are highly homologous to the P. falciparum PfPK5 protein. The CRK2 gene of both species is expressed at a low level during the asexual cell-cycle within the host erythrocytes. The P. berghei CRK2 mRNA is also present in gametocytes and in stages during development in the mosquito, suggesting a role of this protein in different parts of the life cycle. A conserved sequence located in the 5' untranslated region immediately upstream of the initiator ATG has the potential to form a stem-loop structure. Although the CRK2 protein possesses most of the domains that are conserved among cdc2-proteins, neither a recombinant P. knowlesi CRK2 protein nor a recombinant P. berghei protein was able to complement a yeast cdc28ts mutant. Furthermore and in contrast to the P. falciparum PfPK5 protein, a recombinant monomeric P. knowlesi CRK2 protein showed no kinase activity.
Vinkenoog
R
R
Laboratory of Parasitology, Leiden University Medical Centre, The Netherlands.
Sperança
M A
MA
Ramesar
J
J
Thomas
A W
AW
del Portillo
H A
HA
Janse
C J
CJ
Waters
A P
AP
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D017124:Conserved Sequence; D018076:DNA, Complementary; D015870:Gene Expression; D017125:Genes, Protozoan; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D010962:Plasmodium berghei / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D016790:Plasmodium knowlesi / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D011494:Protein Kinases; D015800:Protozoan Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016053:RNA, Protozoan / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics; D017422:Sequence Analysis, DNA
C077833:CRK protein, protozoan; D018076:DNA, Complementary; D015800:Protozoan Proteins; D012333:RNA, Messenger; D016053:RNA, Protozoan; D011494:Protein Kinases