title: Antisera to poly(A)-poly(U)-poly(I) contain antibody subpopulations specific for different aspects of the triple helix.
abstract: Rabbit antibodies to the triple-helical polynucleotide poly(A)-poly(U)-poly(I) were fractionated into three major antibody populations, each recognizing a different conformational feature of the triple-helical immunogen. Two distinct populations were purified from precipitates made with poly(A)-poly(U)-poly(U) and poly(A)-poly(I)-poly(I). The former reacted with double-stranded poly(A)-poly(U) or poly(I)-poly(C), and similar populations could be purified with either double-stranded form. The second population recognized the poly(A)-poly(I) region of the triple helix, and the third required all three strands for reactivity. These immunochemical studies suggest that the poly(A) and poly(U) have the same orientation in the triple-helicical poly(A)-poly(U)-poly(I) as in the double-helical poly(A)-poly(U), in which they have Watson-Crick base pairing.
mesh_terms: D000818:Animals; D000906:Antibodies / Q000032:analysis*; D003168:Complement Fixation Tests; D005779:Immunodiffusion; D009690:Nucleic Acid Conformation; D011061:Poly A; D011069:Poly I; D011072:Poly U; D011131:Polyribonucleotides / Q000276:immunology*; D011817:Rabbits
chemical_list: D000906:Antibodies; D011131:Polyribonucleotides; D011061:Poly A; D011069:Poly I; D011072:Poly U