Viruses mengo

Krishnaswamy, S., Rossmann, M.G. Structural refinement and analysis of mengo virus. /. Mol. Biol. 

Menaquinones (vitamin K2) 818, 821 Mengo virus 247 Menkes disease 883 Mercaptans 624 Mercaptides 550 Mercaptoethanol 98... 

Related picoma viruses such as human rhinoviruses (Fig. 7-15), foot-and-mouth disease virus, parvo-virus, and Mengo virus have similar architectures. The small (diameter 25 nm) single-stranded DNA bacteriophages such as ( )X174 also have three different coat proteins, one of which forms small hollow spikes at the vertices of the icosahedral shell (Fig. 5-41A). ... 

The outer surface of FMDV is relatively smooth. Unlike HRV14 or Mengo virus there were not any major canyons or pits in the surface (figure 10.24). Rossmann et al (1985) proposed that a canyon on the surface of HRV14 was the site of cell attachment and which was inaccessible to antibody. This shielded HRV14 from immune surveillance. 

A comparison of the FMDV proteins with the other viral proteins places Mengo virus roughly midway between HRV14 and FMDV in terms of evolution. 

Figure 10.24 Pentameric association of protomers. Orthogonal views of the virtual bonds joining a-carbon atoms for the pentamers of (a) FMDV, (b) Mengo virus and (c) HRV14 respectively. From Achaiya et al (1989) with permission, copyright 1989 Macmillan Magazines Ltd.

AMINO- AND CARBOXYL-TERMINAL SEQUENCES OF THE MAJOR CAPSID POLYPEPTIDES OF MENGO VIRUS... 

DISTRIBUTION OF THE CAPSID POLYPEPTIDES WITH RESPECT TO THE SURFACE OF THE MENGO VIRUS PARTICLE... 

The experimental data pertaining to the structure of the Mengo virus particle can be summarized as follows. 

Information regarding the assembly of picomaviruses has been obtained largely from the characterization of subviral particles found in infected cells. In the case of poliovirus these include 6 and 15-14 particles, 80 "procapsids and 125 "provirions (68, 69, 70). The cardioviruses do not produce stable procapsids or provirions in vivo however, 15 and 14 particles have been identified in EMC virus-infected cells (7I), and recently a 5OS particle has been isolated from Mengo virus-infected cells (75T Relationships among... 

The early stages in Mengo virus assembly are not clear since (eya) is the smallest subviral particle identified thus far. 

SCRABA, D.G., KAY, C.M. and COLTER, J.S. Physicochemical studies of the three variants of Mengo virus and their constituent ribonucleates. J. Mol. Biol. (I967), 26, 67-79. 

PEREZ-BERCOIT, R. and GARDEE, M. The genomic ERA of Mengo virus. I. Location of the poly(C) tract. Virology (1977) ... 

KAY, C.M., COLTER, J.S. and OIKAWA, K. Circular dichroism studies on Mengo virus variants and their constituent ribonucleates. Can. J. Biochem. (I970), 48, 94O-943. 

PAUCHA, E., SIEHAPER, J. and COLTER, J.S. Synthesis of viral-specific polypeptides in Mengo virus-infected L cells evidence for asymmetric translation of the viral genome. Virology (1974), iL, 515-326. 

Polypeptide synthesis directed by (a) Mengo virus RNA and (b) poly (U,C) in Cont. S-10 and Int. S-10 pre-incubated for different times. Results are given as the counts per minute of leucine incorporation... 

Most of the cell-free extracts used in these studies had been pre-incubated to reduce the translation of endogenous mRNA. Since different preparations of lysates exhibited varying degrees of interferon-induced inhibition, we studied the influence of the length of time of pre-incubation on the interferon-induced inhibition of vitro protein synthesis. e could establish that the ability of cell-free extracts to translate mengo virus RNA was a function of the time of pre-incubation. The ability of an extract from interferon-treated (int. S-10) cells to translate mengo virus RNA was not impaired when compared with an extract from control cells until between 60 and 90 of pre-incubation. At this point, although the activity of the control extract declined somewhat, the activity of the Int. S-10 declined much more rapidly. 

Protein synthesis directed by mengo virus ENA (60 ixg/ml) was assayed in the absence and presence of added total calf liver tENA (60 jig/ml) and tKNA Q (30 ing/ml). Eesults are shown as the incorporation of radioactivity into hot trichloroacetic acid-insoluble material. 

Figure 2. SDS-polyacrylamide gel analysis of proteins synthesized in response to mengo virus MA by Cont.S-10 and Int.S-10 pre-incubated for different times, methionine is...

C. Analysis of the Polypeptides Synthesized with Mengo Virus MA... 

Addition of dsENA to extracts prepared from interferon-treated cells caused 80-90% inhibition of mengo virus EEA translation, regardless of the time of pre-incubation (Table 5) The same dose of dsEEA caused an inhibition of only 8-15% in control extracts. 

Table 5 Effect of added dsRNA and tRNA on mengo virus RNA...

In marked contrast with mengo virus RNA, poly (lJ,C) translation was essentially unaffected by the addition of dsRNA to cell-free extracts from interferon-treated cells and in the presence of dsRNA, tRNA was still able to reverse the interferon-induced inhibition apparent in extracts pre-incubated for 75 (Table 4) Thus, with two doses of poly(l) poly(C), which gave 80% inhibition of mengo RNA translation in interferon-treated cell extracts pre-incubated for 15 min, only a slight effect (12%) on poly (U,C) translation was observed. After pre-incubation for 75 min, translation of poly (lJ,C) by the interferon-treated cell extract was... 

When the extent of initiation was directly measured as the amount of N-terminal methionine present in peptides synthesized with mengo virus RHA as messenger (Table 5)> it was shown that addition of dsRRA to extracts from interferon-treated cells reduced the amount of N-terminal methionine by Incorporation... 

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