期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1978
卷号：75
期号：2
页码：635-639
DOI：10.1073/pnas.75.2.635
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Short-labeled 4.5S RNA molecules isolated from the posterior silk gland of Bombyx mori can be separated by two-dimensional polyacrylamide gel electrophoresis into many discrete species, some of which are radiochemically pure by the criteria of RNA fingerprinting. One region of the gel contains two precursor RNAs, one to each of the known alanine transfer RNAs. Each precursor tRNAAla molecule contains all of the internal oligonucleotides present in the corresponding tRNAAla species plus new 5'-and 3'-terminal sequences. Precursor molecules to tRNA1Gly (which differ from each other in size) are contained in two other gel regions, and a fourth region contains a precursor to tRNA2Gly. Both of the transcription initiator purine tetraphosphate nucleosides are present in unfractionated tRNA precursor mixtures, with pppA- predominating over pppG-. Minor nucleotides are also present in B. mori tRNA precursors. No polycistronic tRNA gene transcripts were observed.
