title: Electron microscopic evidence of circular molecules in 9-S globin mRNA from rabbit reticulocytes.
abstract: 9S globin mRNA prepared by the proteinase K method from polysomes of rabbit reticulocytes consists of 40% circular molecules as revealed by electron microscopy, if spreading of the molecules is performed from a solution of 50% formamide, 0.5 M NaCl, 25 mM Tris, 10 mM EDTA, pH 8, after 16 h incubation at 42 degrees C. We assume a noncovalent nature of the circularization because of the fact that a total transformation into the well known linear form occurs if strong denaturing conditions for spreading were used. The biological significance of the circular globin mRNA molecules is unknown.
mesh_terms: D000818:Animals; D019286:Endopeptidase K; D010450:Endopeptidases / Q000378:metabolism; D005914:Globins / Q000096:biosynthesis; D008854:Microscopy, Electron; D009690:Nucleic Acid Conformation; D011132:Polyribosomes / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis*; D011817:Rabbits; D012156:Reticulocytes / Q000032:analysis*
chemical_list: D012333:RNA, Messenger; D005914:Globins; D010450:Endopeptidases; D019286:Endopeptidase K