Cytosines do it, thymines do it, even pseudouridines do it--base flipping by an enzyme that acts on RNA.
In the December 28, 2001 issue of Cell, Hoang and Ferré-D'Amaré report the structure of a tRNA pseudouridine synthase, showing the target uridine flipped out from the tRNA and confirming that base flipping is not limited to enzymes that act on DNA.
Cheng
Xiaodong
X
Emory University School of Medicine, Department of Biochemistry, Atlanta, GA 30322, USA.
Blumenthal
Robert M
RM
D020029:Base Pairing; D003596:Cytosine / Q000378:metabolism*; D019751:Intramolecular Transferases / Q000378:metabolism*; D008958:Models, Molecular; D008968:Molecular Conformation; D009690:Nucleic Acid Conformation; D011560:Pseudouridine / Q000378:metabolism*; D012313:RNA / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D012270:Ribosomes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013941:Thymine / Q000378:metabolism*
D011560:Pseudouridine; D012313:RNA; D003596:Cytosine; D019751:Intramolecular Transferases; C023199:tRNA-pseudouridine synthase I; D013941:Thymine