title: Molecular characterization of iron binding proteins, transferrin and ferritin heavy chain subunit, from the bumblebee Bombus ignitus.
abstract: Transferrin and ferritin are iron-binding proteins involved in transport and storage of iron as part of iron metabolism. Here, we describe the cDNA cloning and characterization of transferrin (Bi-Tf) and the ferritin heavy chain subunit (Bi-FerHCH), from the bumblebee Bombus ignitus. Bi-Tf cDNA spans 2340 bp and encodes a protein of 706 amino acids and Bi-FerHCH cDNA spans 1393 bp and encodes a protein of 217 amino acids. Comparative analysis revealed that Bi-Tf appears to have residues comprising iron-binding sites in the N-terminal lobe, and Bi-FerHCH contains a 5'UTR iron-responsive element and seven conserved amino acid residues associated with a ferroxidase center. The Bi-Tf and Bi-FerHCH cDNAs were expressed as 79 kDa and 27 kDa polypeptides, respectively, in baculovirus-infected insect Sf9 cells. Northern blot analysis revealed that Bi-Tf exhibits fat body-specific expression and Bi-FerHCH shows ubiquitous expression. The expression profiles of the Bi-Tf and Bi-FerHCH in the fat body of B. ignitus worker bees revealed that Bi-Tf and Bi-FerHCH are differentially induced in a time-dependent manner in a single insect by wounding, bacterial challenge, and iron overload.
authors.affiliation: College of Natural Resources and Life Science, Dong-A University, Busan 604-714, Republic of Korea.
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.forename: Bo Yeon
authors.initials: BY
authors.lastname: Kim
authors.forename: Kwang Sik
authors.initials: KS
authors.lastname: Lee
authors.forename: Hyung Joo
authors.initials: HJ
authors.lastname: Yoon
authors.forename: Zheng
authors.initials: Z
authors.lastname: Cui
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.forename: Jing Ming
authors.initials: JM
authors.lastname: Jia
authors.forename: Doh Hoon
authors.initials: DH
authors.lastname: Kim
authors.forename: Hung Dae
authors.initials: HD
authors.lastname: Sohn
authors.forename: Byung Rae
authors.initials: BR
authors.lastname: Jin
mesh_terms: D000818:Animals; D001516:Bees / Q000737:chemistry* / Q000235:genetics; D001665:Binding Sites; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005293:Ferritins / Q000737:chemistry* / Q000235:genetics; D005786:Gene Expression Regulation; D007313:Insecta; D033862:Iron-Binding Proteins; D021122:Protein Subunits; D020218:Response Elements; D014018:Tissue Distribution; D014162:Transfection; D014168:Transferrin / Q000737:chemistry* / Q000235:genetics
chemical_list: D018076:DNA, Complementary; D033862:Iron-Binding Proteins; D021122:Protein Subunits; D014168:Transferrin; D005293:Ferritins