Genome-linked protein

These data show that the physical properties of the genome-linked proteins of two picornaviruses depend on the infecting virus rather than the host cell, suggesting that they are virus-coded. It should... 

Our strategy to identify the function of the genome-linked protein has been then, to analyze the step in viral replication at which VPg becomes attached to the viral RHA. For example, if VPg were to be found in replicative structures of polio RHA, its attachment to RHA (and consequently its function) might be related to replication of RNA. As polio replicative intermediate (Rl)... 

Light absorption 122,123. See also Absorption spectra of DNA 209 Lily, genome 12 Lineweaver-Burk plot 460 Link protein 181 Linkage between genes 18 Linoleic acid 381 Lipase(s) 634 - 637... 

The existence of a phosphodiester bond between proteins and nucleic acids is by no means unique to topoisomerases. For example, the covalent bond formed between the poliovirus RNA-linked protein (VPg) and the 5 terminus of the poliovirus RNA has been determined to be a phosphoryl-tyrosine linkage (Ambros and Baltimore, 1978). Proteins are found covalently attached to the 5 termini of the genomes of phage 29 and adenovirus via a phosphoryl-serine bond (Hermoso and Salas, 1980 Desiderio and Kelly, 1981). It seems, therefore, that a phosphodiester bond between DNA and either serine or tyrosine residues in proteins may be a common feature of many proteins involved in DNA metabolism. 

A. Positive-Stranded RNA Viruses - The positive-stranded RNA viruses are best represented by the picornaviruses of which poliovirus is a model virus. Poliovirus contains a single-stranded genome RNA, which has a MW of 2.5x10 (7700 nucleotides), and four viral structural proteins. Upon entrance into a cell, the genome RNA is translated into one large polypeptide which is cleaved proteolytically to produce all the viral proteins (see below). The 5 ends of picornavirus genome RNAs are unique as they contain a covalently linked protein. The protein (VPg) has a MW of 6-12,000, and has both a basic and hydrophobic nature. It is linked... 

Osborne-Lawrence SL, Sinclair AK, Hicks RC, Lacey SW, Eddy RE, Jr., Byers MG, Shows TB, Duby AD. Complete amino acid sequence of human cartilage link protein (CRTLl) deduced from cDNA clones and chromosomal assignment of the gene. Genomics 1990 8 562-567. 

Fig. 4 Separation of genomic DNA from uncross-linked proteins by 5-8 M urea gradient. Jurkat cells were grown in the presence of pHJthymidine and [ CJIeucine for a period of 24 hr. Cells were then either subjected to in vivo formaldehyde cross-linking for a period of 2 hr (upper panel), or untreated (bottom panel). Cells were lysed and loaded onto 5-8 M urea gradients and centrifuged as described in Section IV,A,3. Following centrifugation the gradients were fractionated and H and C counts were determined by liquid scintillation counting.

The 5 iid. of the nascent chains seems to be capped (63, 64) by a terminally-linked protein, covalently bound to the 5 end of the genomic RNA of picornaviruses (65-69). This led to the suggestion that the terminally-linked protein might be needed as a primer for the viral replicase (64, and for a more detailed discussion, see chapter 9)> t>nt there is not yet experimental evidence to support the notion of a direct involvement of this protein in the process of RNA replication. 

Uversky VN, Oldfield CJ, Midic U, et al. Unfoldomics of human diseases linking protein intrinsic disorder with diseases. BMC Genomics. 2009 10(suppl 1) S7. 

Recent developments in the synthesis of oligonucleotide-peptide conjugates include the synthesis of an RNA-peptide conjugate related to viral protein genome-linked (VPg) protein. The synthesis was carried out by first synthesising the peptide portion using Fmoc chemistry and using... 

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