Cloning and expression in E. coli of the malarial sporozoite surface antigen gene from Plasmodium knowlesi

Ellis, J M; Ozaki, Luiz Shozo; Gwadz, Robert W.; Cochrane, Alan H.; Nussenzweig, Victor; Nussenzweig, Ruth S.; Godson, G. N.

doi:10.1038/302536a0

Cited by 156 publications

(58 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Plasmid pEG81 (23) was used as a target for TnS mutagenesis. It contains part of the coding region of the CS gene of P. knowlesi that was isolated from a cDNA library of sporozoite mRNA by G-C tailing using terminal transferase and inserted into the Pst I site of pBR322 (28).…”

Section: Resultsmentioning

confidence: 99%

A temperature-dependent pBR322 copy number mutant resulting from a Tn5 position effect.

Lupski¹,

Projan²,

Ozaki³

et al. 1986

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

In the process of randomly mutagenizing a recombinant pBR322 clone with transposon TnS, a high copy number plasmid mutant, pLO88, has been isolated. The copy number phenotype of pLO88 is observed only at elevated temperatures, >37C, and is due to the precise position of a TnS insertion. Nucleotide sequence of the TnS-pBR322 junction reveals that TnS-88 has inserted into an open reading frame that codes for a 63 amino acid protein previously shown to negatively regulate pBR322 plasmid copy number. By deleting portions of the TnS it is shown that the copy number phenotype is due not only to the insertion of TnS in pBR322 but also to the requirement that some TnS sequences remain intact. It appears that an outwardly directed TnS promoter inlitiates the synthesis of a transcript (RNA X) that interferes with the normal repressor RNA (RNA I)-primer RNA (RNA II) interaction at elevated temperatures.Initiation of DNA replication for ColEl plasmids depends on the formation of an RNA primer by the action of RNA polymerase and RNase H. Synthesis of the primer precursor transcript (RNA II) is initiated 555 base pairs (bp) upstream of the origin of DNA replication and this then forms a persistent hybrid with the template DNA near the origin of DNA replication. RNase H cleaves the hybridized transcript at the origin and this processed RNA II is used as a primer for DNA synthesis by DNA polymerase 1 (1-4). Regulation of the promoter for RNA II appears to be sufficient to control plasmid copy number (5). Primer formation is inhibited by a plasmid-specified 108-nucleotide repressor RNA, RNA I (6-8). RNA I synthesis starts 445 bp upstream from the origin of replication and proceeds in the opposite direction from RNA II synthesis. RNA I terminates near the site where RNA II synthesis starts and is therefore a complement of RNA II. When RNA I binds to RNA II, primer formation is inhibited (7, 9). Point mutations that affect formation and structure of RNA I will also affect RNA II and these have

show abstract

Section: Resultsmentioning

confidence: 99%

A temperature-dependent pBR322 copy number mutant resulting from a Tn5 position effect.

Lupski¹,

Projan²,

Ozaki³

et al. 1986

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Tandemly repeated sequences are known to characterize a number of surface proteins of malarial parasites. For example, the circumsporozoite protein of Plasmodium falciparum consists almost entirely of tandem repeats of 4 amino acids (25), while that of Plasmodium knowlesi contains 12 repeats of a 12-amino acid unit (26). These Plasmodium circumsporozoite proteins show a high degree of antigenicity and are able to serve as the targets for neutralizing antibodies.…”

Section: Discussionmentioning

confidence: 99%

Cloning of a brain protein identified by autoantibodies from a patient with paraneoplastic cerebellar degeneration.

Dropcho¹,

Chen²,

Posner³

et al. 1987

Proc. Natl. Acad. Sci. U.S.A.

145

View full text Add to dashboard Cite

Autoantibodies directed against neuronal proteins have been identified in some patients with paraneoplastic cerebellar degeneration. To identify the molecular targets for these autoantibodies, we constructed a lambda gt11 cDNA expression library from human cerebellum and screened the library with IgG from a patient with paraneoplastic cerebellar degeneration. A single clone, pCDR2, produced a fusion protein that reacted strongly with the patient's IgG. The isolated pCDR2 clone was used to identify six overlapping cDNA clones. Sequencing of the pCDR clones revealed a distinctive pattern consisting of a unit of 18 nucleotides (6 amino acids) repeated in tandem along the entire cDNA sequence. This sequence is unlike any previously described eukaryotic gene. Southern blot analysis was consistent with single-copy representation of the CDR (cerebellar degeneration-related) gene in the human and mouse genome. RNA blotting studies with normal tissues showed expression of the CDR gene to be largely restricted to brain. Expression of the CDR message was also noted in cell lines derived from cancers of neuroectodermal, kidney, and lung origin.

show abstract

“…CS has long been considered an Ag crucially implicated in protective immunity against the pre-erythrocytic (PE) stages of the Plasmodium infection (1). The gene coding for this Ag was the first Plasmodium gene to be cloned (2), and the first Plasmodium falciparum subunit vaccine tested in human volunteers was based on CS (3). CS-based vaccines are still at the forefront of malaria vaccine development (4,5).…”

Section: T He Circumsporozoite Protein (Cs)mentioning

confidence: 99%

Are Extensive T Cell Epitope Polymorphisms in the Plasmodium falciparum Circumsporozoite Antigen, a Leading Sporozoite Vaccine Candidate, Selected by Immune Pressure?

Kumkhaek¹,

Phra-ek

Rénia³

et al. 2005

The Journal of Immunology

View full text Add to dashboard Cite

Protective cellular immune responses depend on MHC presentation of pathogen-derived Ag fragments. MHC diversity renders this process sensitive to point mutations coding for altered amino acid sequence of the short target Ag-derived peptides epitopes. Thus, in a given host, a pathogen with an altered epitope sequence will be more likely to escape detection and elimination by the immune system. At a population level, selection by immune pressure will increase the likelihood of polymorphism in important pathogen antigenic epitopes. This mechanism of immune evasion is found in viruses and other pathogens. The detection of polymorphic hot spots in an Ag is often taken as a strong indication of its role in protective immunity. We provide evidence that polymorphisms in the T cell epitopes of a malaria vaccine candidate are unlikely to have been selected by immune pressure in the human host.

show abstract

Cloning and expression in E. coli of the malarial sporozoite surface antigen gene from Plasmodium knowlesi

Cited by 156 publications

References 20 publications

A temperature-dependent pBR322 copy number mutant resulting from a Tn5 position effect.

A temperature-dependent pBR322 copy number mutant resulting from a Tn5 position effect.

Cloning of a brain protein identified by autoantibodies from a patient with paraneoplastic cerebellar degeneration.

Are Extensive T Cell Epitope Polymorphisms in the Plasmodium falciparum Circumsporozoite Antigen, a Leading Sporozoite Vaccine Candidate, Selected by Immune Pressure?

Contact Info

Product

Resources

About