title: Identification and sequencing of cDNA clones for the rodent negative acute-phase protein alpha 1-inhibitor 3.
abstract: Rat alpha 1-inhibitor 3 clones were isolated by immunological screening of a lambda gt11 cDNA library prepared from rat liver poly(A)-rich RNA. The recombinant cDNA clones were identified by the absence of their immunoprecipitable products following hybrid-arrested in vitro translation. The size of the cognate poly(A)-rich RNA was estimated to be roughly 5000 residues. Approximately 16 h after induction of inflammation the amount of alpha 1-inhibitor 3 poly(A)-rich RNA decreases as shown by dot-blot hybridization and Northern analyses. The response of this negative acute-phase plasma protein to inflammation may therefore be considered to be at the pretranslational level. The characterized DNA constitutes an open reading frame of 225 amino acids followed by a canonical eucaryotic polyadenylation signal and a poly(A) tail. Sequence microheterogeneity, particularly in the 3'-flanking region was observed. An amino acid homology of 70% for alpha 1-inhibitor 3 with human and rodent alpha 2-macroglobulin emphasizes the evolutionary relationship of the macroglobulins.
mesh_terms: D000209:Acute-Phase Proteins; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics*; D006801:Humans; D011480:Protease Inhibitors / Q000235:genetics*; D051381:Rats; D000511:alpha-Macroglobulins / Q000235:genetics
chemical_list: D000209:Acute-Phase Proteins; D011480:Protease Inhibitors; C017894:alpha 1-inhibitor 3; D000511:alpha-Macroglobulins; D004247:DNA