title: A modified nucleotide in the poly(A) tract of maize RNA.
abstract: poly(A)+ RNA was isolated from maize by affinity chromatography on columns of oligo(dT)-cellulose. A modified nucleotide ('X') was detected in ribonuclease T2 digests of the RNA as part of a resistant dinucleotide. The dinucleotide was detected by means of the polynucleotide kinase-mediated transfer of a radioactive phosphate atom from adenosine triphosphate to the 5'-OH position of the dinucleotide. Intact poly(A) tracts were released from poly(A)+ RNA by digestion with ribonuclease T1 and A in a high salt buffer and were isolated by oligo(dT)-cellulose chromatography. The poly(A) preparation was found to consist of a series of polyadenylate fragments which varied in chain length from approximately 17 to greater than 70. The modified nucleotide was shown to occupy an internal position in these poly(A) tracts.
mesh_terms: D002846:Chromatography, Affinity; D002855:Chromatography, Thin Layer; D004720:Endonucleases / Q000378:metabolism; D004722:Endoribonucleases; D010944:Plants / Q000032:analysis*; D011061:Poly A / Q000032:analysis* / Q000302:isolation & purification*; D012313:RNA / Q000302:isolation & purification*; D012333:RNA, Messenger; D012260:Ribonucleases / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D011061:Poly A; D012313:RNA; D004720:Endonucleases; D004722:Endoribonucleases; D012260:Ribonucleases; C022543:ribonuclease T(2)