title: cDNA encoding an immunogenic region of a 22 kilodalton surface protein of Eimeria acervulina sporozoites.
abstract: cDNA encoding an immunogenic region of a 22 kDa surface protein of Eimeria acervulina sporozoites was cloned and expressed in the bacteriophage lambda gt11 vector. The recombinant beta-galactosidase fusion protein, designated MA1, has an apparent molecular size of 125 kDa. Immunofluorescence staining of intact E. acervulina sporozoites and merozoites and immunoblotting of 125I-surface labeled protein from both stages revealed exclusive expression of the cloned cDNA in the sporozoite stage. The gene encoding the 22 kDa surface protein appears to exist as a single copy sequence as revealed by Southern blot hybridization utilizing the cDNA insert as a probe. Although not recognized by immune serum, purified recombinant MA1 antigen induced significant in vitro activation of T lymphocytes obtained from chickens immune to E. acervulina. DNA sequencing and hydropathic analysis of the predicted amino acid sequence revealed a central hydrophilic region surrounded by two hydrophobic areas which may represent exposed and transmembrane regions of the protein.
authors.affiliation: U.S. Department of Agriculture, Animal Parasitology Institute, Beltsville, MD 20705.
authors.forename: M C
authors.initials: MC
authors.lastname: Jenkins
authors.forename: H D
authors.initials: HD
authors.lastname: Danforth
authors.forename: H S
authors.initials: HS
authors.lastname: Lillehoj
authors.forename: R H
authors.initials: RH
authors.lastname: Fetterer
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics*; D001483:Base Sequence; D004247:DNA / Q000235:genetics*; D015342:DNA Probes; D004539:Eimeria / Q000235:genetics / Q000276:immunology*; D008565:Membrane Proteins / Q000235:genetics*; D008970:Molecular Weight; D011994:Recombinant Proteins
chemical_list: D000953:Antigens, Protozoan; D015342:DNA Probes; D008565:Membrane Proteins; D011994:Recombinant Proteins; D004247:DNA