Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 1991 Feb;127(2):345-53.
doi: 10.1093/genetics/127.2.345.

Circumsporozoite protein genes of malaria parasites (Plasmodium spp.): evidence for positive selection on immunogenic regions

A L Hughes  1
Affiliations
Comparative Study

Circumsporozoite protein genes of malaria parasites (Plasmodium spp.): evidence for positive selection on immunogenic regions

A L Hughes. Genetics. 1991 Feb.

Abstract

The circumsporozoite (CS) protein is a cell surface protein of the sporozoite, the stage of the life cycle of malaria parasites (Plasmodium spp.) that infects the vertebrate host. Analysis of DNA sequences supports the hypothesis that in Plasmodium falciparum, positive Darwinian selection favors diversity in the T-cell epitopes (peptides presented to T cells by host MHC molecules) of the CS protein. In gene regions encoding T cell epitopes of P. falciparum, the rate of nonsynonymous nucleotide substitution is significantly higher than that of synonymous substitution, whereas this is not true of other gene regions. Furthermore nonsynonymous nucleotide substitutions in these regions cause a change of amino acid residue charge significantly more frequently than expected by chance. By contrast, in Plasmodium cynomolgi, the same regions show no evidence of positive selection, and residue charge is conserved. The CS protein has a central repeat region, which is the target of host antibodies. In P. falciparum, the amino acid sequence of the repeat region is conserved within and between alleles. In P. cynomolgi, on the other hand, there is evidence that positive selection has favored evolution of two different repeat types within a given allele.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Mol Biol Evol. 1990 Nov;7(6):515-24 - PubMed
    1. Parasitol Today. 1989 May;5(5):138-42 - PubMed
    1. Mol Biol Evol. 1986 Sep;3(5):418-26 - PubMed
    1. Mol Biol Evol. 1989 May;6(3):290-300 - PubMed
    1. Science. 1985 May 24;228(4702):996-9 - PubMed

Publication types