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:1980
卷号:77
期号:9
页码:5302-5306
DOI:10.1073/pnas.77.9.5302
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Double-stranded cDNA has been synthesized from a polyadenylylated potato spindle tuber viroid (PSTV) template and inserted in the Pst I endonuclease site of plasmid pBR322 by using the oligo(dC){middle dot}oligo(dG)-tailing procedure. Tetracycline-resistant ampicillin-sensitive transformants contained sequences complementary to PSTV [32P]cDNA, and one recombinant clone (pDC-29) contains a 460-base-pair insert. This cloned double-stranded PSTV cDNA contains the cleavage sites for six restriction endonucleases predicted by the published primary sequence of PSTV as well as one additional site each for Ava I, Hae III, Hpa II, and Sma I. The additional Ava I, Hpa II, and Sma I sites are explained by the presence of a second C-C-C-G-G-G sequence in the cloned double-stranded cDNA. The largest fragment released by Hae III digestion contains approximately 360 base pairs. These results suggest that we have cloned almost the entire sequence of PSTV, but the sequence cloned differs slightly from that published. Hybridization probes derived from pDC-29 insert have allowed detection and preliminary characterization of RNA molecules having the same size as PSTV but the opposite polarity. This RNA is present during PSTV replication in infected tomato cells.