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：1973
卷号：70
期号：4
页码：1122-1126
DOI：10.1073/pnas.70.4.1122
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Highly purified globin mRNA from ducks was copied with RNA-directed DNA polymerase from avian myeloblastosis virus into anti-messenger DNA. With excess RNA, more than 90% of this DNA annealed back to its template with a Cot/2 value of 7.5 x 10-4 mol{middle dot}sec{middle dot} liter-1; the melting temperature of the hybrid was 86{degrees}. Giant nuclear RNA fractions with sedimentation coefficients of more than 50 S formed hybrids of almost equal stability at Cot/2 values of 0.05-0.42 mol{middle dot}sec{middle dot} liter-1, indicating amRNA content of 0.3-1.5%. 12S RNA from the same polyribosomes and nuclear giant RNA from HeLa cells did not cross-hybridize. Although a large part of the giant RNA broke down in 99% dimethylsulfoxide gradients, RNA fractions sedimenting faster than 28S rRNA still were found to consist of up to 0.03% globin mRNA sequences. Thus, the mRNA sequences are contained in the covalent structure of giant nuclear precursors, which are termed precursor-mRNA.
关键词：precursor-mRNA ; hemoglobin ; RNA-directed DNA polymerase ; anti-messenger DNA ; hybridization
