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A J Caton

Publications and source records attributed to A J Caton.

43 records · Page 3Linked to original sources
PubMed1986

Comparative sequence analysis of CO17-1A antigen-specific monoclonal antibodies.

Sequence analysis of murine monoclonal antibodies (MAbs) specific for the CO17-1A antigen is being performed to assess the structural basis for antibody specificity for this antigen. Preliminary data reveal that the heavy chain variable regions of MAbs GA733 and CO17-1A (designated Ab1s since they were isolated following immunization with CO17-1A antigen) most likely utilize distinct members of the same gene family. Remarkably, they also display identical amino acid sequences in their heavy chain CDR3 regions, reflecting absolute nucleotide sequence identity across their VH-D-JH junctions. Since these junctional sequences are randomly generated during the assembly of immunoglobulin genes and in general display enormous diversity, this homology suggests an important role for heavy chain CDR3 in determining specificity for the CO17-1A antigen in these antibodies.

Amino Acid Sequence↗
PubMed1983

Antigenicity and evolution amongst recent influenza viruses of H1N1 subtype.

The sequence of the HA1 subunit region of the haemagglutinin gene of influenza A/USSR/90/77, and A/Brazil/11/78, A/Lackland/3/78, A/England/333/80 and A/India/6263/80 was determined by dideoxy-sequencing methods using total virion RNA and specific oligonucleotide primers for reverse transcriptase. These 1977-1980 strains share a minimum of 85% amino acid sequence homology with influenza A/PR/8/34. Most of the surface amino acid substitutions which occurred during the evolution of A/PR/8/34 to A/USSR/90/77 and subsequently in the 1978-1980 strains are located in the 4 antigenic sites previously defined by an analysis of laboratory-selected mutants of A/PR/8/34. We deduce an evolutionary pathway for the 1977-80 strains and suggest their different epidemic properties may be a consequence of only a few amino acid changes.

Antigens, Viral↗
PubMed1982

The antigenic structure of the influenza virus A/PR/8/34 hemagglutinin (H1 subtype).

We have constructed an operational antigenic map of the hemagglutinin of influenza virus A/PR/8/34, which indicates the presence of five immunodominant antigenic regions exhibiting various degrees of operational linkage. These sites have been located by the identification of changed amino acid residues in mutant viruses that are antigenically altered at each site. Comparison of the antigenic features with the three-dimensional structure of the H3 subtype hemagglutinin shows that the antigenic sites correspond to four topographically distinct regions of the surface of the protein. One of the sites is formed when two regions that are widely separated in the hemagglutinin monomer associate in the assembled trimer. The location of the sites relative to those proposed for the H3 subtype hemagglutinin suggests that carbohydrate modulates the antigenicity of specific regions of the hemagglutinin.

Amino Acid Sequence↗
PubMed1980

Structure of the host-derived sequences present at the 5' ends of influenza virus mRNA.

Nucleotide sequence analysis of the terminal virus-coded regions of a clone of the matrix gene of influenza virus indicated that the region corresponding to the 5' end of the mRNA contains an additional 13 non-virus coded nucleotides. Using the dideoxy-chain termination sequencing method with a restriction fragment derived from this clone, we have determined that the 5' ends of matrix gene mRNAs contain a heterogenous sequence of 9-15 nucleotides. In addition, the data indicate that the 3' terminal nucleotide of matrix gene virion RNA is not transcribed into mRNA, transcription of influenza virus-specific sequences commencing with the penultimate nucleotide at the 3' end of viron RNA.

Base Sequence↗
PubMed1979

New procedure for the production of influenza virus-specific double-stranded DNA's.

A novel technique is described for the production of pure, full-length influenza virus ds DNA's corresponding to each segment of the influenza virus genome, and suitable for molecular cloning and restriction endonuclease mapping. The method involves the synthesis of DNA complementary to both virion (negative strand) and messenger (positive strand) RNA, gel purification and annealing. By avoiding the use of SI nuclease, which often removes the terminal regions of DNA duplexes, the method allows transcription of the total sequence information of influenza virion and messenger RNA's into a ds DNA form.

Avian Myeloblastosis Virus↗