Abstract
The origin recognition complex (ORC) is a multisubunit protein composed of six polypeptides that binds to replication origins and is essential for the initiation of chromosomal DNA replication. Using the Vectorette technique, we have isolated a novel gene encoding an ORC1-like protein from the human malaria parasite Plasmodium falciparum. The gene has no introns and encodes a protein (PfORC1) of 1189 amino acid residues with a predicted molecular mass of 139 kDa. PfORC1 contains all conserved sequences in the ORC1/Cdc6/Cdc18 family and displays the highest homology to the Schizosaccharomyces pombe ORC1. However, PfORC1 possesses an extensive N-terminal segment with several interesting features including multiple potential phosphorylation sites, a large proportion of charged amino acids, four copies of a heptamer repeat, two nuclear localisation signals, and a leucine zipper motif. Southern blot analyses show that the Pforc1 gene is present as a single copy per haploid genome and is located on chromosome 12. A 5600 nucleotide transcript of this gene is expressed predominantly in the sexual erythrocytic stage, indicating that PfORC1 may be involved in gametogenesis during which DNA is quickly replicated.
Publication Date
2003-03-01
Publication Title
Parasitology International
Volume
52
Issue
1
Publisher
Elsevier BV
ISSN
1383-5769
Embargo Period
2024-11-19
First Page
41
Last Page
52
Recommended Citation
Li, J., & Cox, L. (2003) 'Characterisation of a sexual stage-specific gene encoding ORC1 homologue in the human malaria parasite Plasmodium falciparum', Parasitology International, 52(1), pp. 41-52. Elsevier BV: Available at: 10.1016/s1383-5769(02)00079-x
