title: Short report: molecular cloning and characterization of a putative binding protein of Babesia caballi.
abstract: A composite 2,206 nucleotide DNA sequence encoding a putative immunoglobulin-binding protein (BiP) was constructed from a sequence obtained from Babesia caballi cDNA library clones. The 1,962 nucleotide open reading frame predicts a 72 kD protein with extensive homology with BiPs from Apicomplexa parasites. The BiP gene had a predicted N-terminal signal sequence of 18 amino acids and a C-terminal tetrapeptide sequence (Ser-Asp-Glu-Leu) for signaling in the endoplasmic reticulum lumen. The recombinant protein expressed in baculovirus showed an apparent mass of 72 kD, which is identical to that of the native B. caballi protein. Monoclonal antibodies (MAbs) against B. caballi BiP reacted strongly with extracellular merozoites, but not in early intraerythrocytic stage. Detailed observation showed that the reaction of MAbs against pear-shaped forms was markedly irregular, with either no reaction, or reaction with one or two brightly fluorescent pear-shaped forms (two parasites) of B. caballi.
authors.affiliation: Department of Veterinary Parasitology, School of Veterinary Medicine and Animal Sciences, Kitasato University, Towada, Aomori, Japan. ikadai@vmas.kitasato-u.ac.jp
authors.forename: Hiromi
authors.initials: H
authors.lastname: Ikadai
authors.forename: Yumi
authors.initials: Y
authors.lastname: Takamatsu
authors.forename: Ryoko
authors.initials: R
authors.lastname: Takashiro
authors.forename: Ayaka
authors.initials: A
authors.lastname: Segawa
authors.forename: Noboru
authors.initials: N
authors.lastname: Kudo
authors.forename: Ikuo
authors.initials: I
authors.lastname: Igarashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Oyamada
mesh_terms: D000818:Animals; D001403:Babesia / Q000235:genetics*; D001404:Babesiosis / Q000469:parasitology*; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins / Q000235:genetics*; D006736:Horses; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D018832:Molecular Chaperones / Q000235:genetics*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins; D007143:Immunoglobulin Heavy Chains; D018832:Molecular Chaperones