title: Molecular cloning and characterization of novel splicing variants of human decay-accelerating factor.
abstract: Decay-accelerating factor (DAF) is one of the complement regulatory proteins. Two isoforms of DAF have been identified in humans. In this study, we isolated novel cDNAs encoding five isoforms of DAF from the human lung, which were generated by insertion of new exonic sequences. RT-PCR revealed that all isoforms were expressed in almost all tissues tested, although the expression patterns and levels differed among the tissues. Transfection of isoform vDAF1, 2, and 3 cDNAs into CHO cells showed that these molecules are soluble forms secreted after glycosylation. Isoform vDAF4 and vDAF5 cDNAs included a part of and the entire intron 7 sequence, respectively, and the transfection of vDAF4 cDNA produced a large, glycosylated, membrane-bound form. These results suggest that more than seven isoforms of human DAF are involved in the regulation of complement activation under physiological conditions through their specific structures and localization.
authors.affiliation: Department of Surgery I, Fukushima Medical University School of Medicine, 1-Hikariga-oka, Fukushima 960-1295, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Osuka
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Endo
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Higuchi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Suzuki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Shio
authors.forename: Koichi
authors.initials: K
authors.lastname: Fujiu
authors.forename: Ryuzo
authors.initials: R
authors.lastname: Kanno
authors.forename: Akio
authors.initials: A
authors.lastname: Oishi
authors.forename: Masanori
authors.initials: M
authors.lastname: Terashima
authors.forename: Teizo
authors.initials: T
authors.lastname: Fujita
authors.forename: Mitsukazu
authors.initials: M
authors.lastname: Gotoh
mesh_terms: D017398:Alternative Splicing / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D018958:CD55 Antigens / Q000235:genetics*; D016466:CHO Cells; D003001:Cloning, Molecular; D003167:Complement Activation / Q000235:genetics*; D006224:Cricetinae; D003412:Cricetulus; D018076:DNA, Complementary / Q000235:genetics*; D006801:Humans; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000235:genetics
chemical_list: D018958:CD55 Antigens; D018076:DNA, Complementary; D020033:Protein Isoforms