Biomaterial Database

A small viral RNA is required for in vitro packaging of bacteriophage phi 29 DNA. 1987

P X Guo, and S Erickson, and D Anderson

A small RNA of Bacillus subtilis bacteriophage phi 29 is shown to have a novel and essential role in viral DNA packaging in vitro. This requirement for RNA in the encapsidation of viral DNA provides a new dimension of complexity to the attendant protein-DNA interactions. The RNA is a constituent of the viral precursor shell of the DNA-packaging machine but is not a component of the mature virion. Studies of the sequential interactions involving this RNA molecule are likely to provide new insight into the structural and possible catalytic roles of small RNA molecules. The phi 29 assembly in extracts and phi 29 DNA packaging in the defined in vitro system were strongly inhibited by treatment with the ribonucleases A or T1. However, phage assembly occurred normally in the presence of ribonuclease A that had been treated with a ribonuclease inhibitor. An RNA of approximately 120 nucleotides co-purified with the phi 29 precursor protein shell (prohead), and this particle was the target of ribonuclease action. Removal of RNA from the prohead by ribonuclease rendered it inactive for DNA packaging. By RNA-DNA hybridization analysis, the RNA was shown to originate from a viral DNA segment very near the left end of the genome, the end packaged first during in vitro assembly.

UI	MeSH Term	Description	Entries
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D004279	DNA, Viral	Deoxyribonucleic acid that makes up the genetic material of viruses.	Viral DNA
D005814	Genes, Viral	The functional hereditary units of VIRUSES.	Viral Genes,Gene, Viral,Viral Gene
D006163	Ribonuclease T1	An enzyme catalyzing the endonucleolytic cleavage of RNA at the 3'-position of a guanylate residue. EC 3.1.27.3.	Guanyloribonuclease,RNase T1,Ribonuclease N1,Aspergillus oryzae Ribonuclease,Guanyl-Specific RNase,RNase Apl,RNase F1,RNase Pch 1,RNase ST,Ribonuclease F1,Ribonuclease F2,Ribonuclease ST,Ribonuclease T-1,T 1 RNase,Guanyl Specific RNase,RNase, Guanyl-Specific,RNase, T 1,Ribonuclease T 1,Ribonuclease, Aspergillus oryzae
D001412	Bacillus subtilis	A species of gram-positive bacteria that is a common soil and water saprophyte.	Natto Bacteria,Bacillus subtilis (natto),Bacillus subtilis subsp. natto,Bacillus subtilis var. natto
D001435	Bacteriophages	Viruses whose hosts are bacterial cells.	Phages,Bacteriophage,Phage
D012259	Ribonuclease, Pancreatic	An enzyme that catalyzes the endonucleolytic cleavage of pancreatic ribonucleic acids to 3'-phosphomono- and oligonucleotides ending in cytidylic or uridylic acids with 2',3'-cyclic phosphate intermediates. EC 3.1.27.5.	RNase A,Ribonuclease A,Pancreatic RNase,RNase I,Ribonuclease (Pancreatic),Ribonuclease I,Pancreatic Ribonuclease,RNase, Pancreatic
D012367	RNA, Viral	Ribonucleic acid that makes up the genetic material of viruses.	Viral RNA
D014764	Viral Proteins	Proteins found in any species of virus.	Gene Products, Viral,Viral Gene Products,Viral Gene Proteins,Viral Protein,Protein, Viral,Proteins, Viral