Bipartite structure of the downstream element of the mouse beta globin (major) poly(A) signal.
The downstream region of the mouse beta (major) globin poly(A) signal was mutated and analyzed for function in transfected COS cells. From analysis of unidirectional Bal31 deletions, the 3' boundary of the downstream element was defined as +22 (22 nucleotides downstream from the cleavage site). Analysis of cluster mutations, in which 5 or 6 adjacent bases were replaced with a random CA-containing sequence in a manner that did not alter spacing, confirmed +22 as the 3' boundary of the downstream element. The analysis also revealed two short UG-rich sequences, located from +5 to +10 and from +17 to +22, as major functional components. In contrast, a more refined series of mutations, in which clusters of 3 bases were replaced, failed to cause loss of function. We conclude that the downstream element of the mouse beta globin poly(A) signal is bipartite in structure, and that portions of its sequence are functionally redundant.
Chen
J S
JS
Department of Biological Sciences, Fordham University, Bronx, NY 10458.
Nordstrom
J L
JL
D000818:Animals; D001483:Base Sequence; D004252:DNA Mutational Analysis; D005914:Globins / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D011061:Poly A / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics*; D014407:Tumor Cells, Cultured
D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D011061:Poly A; D005914:Globins