The vaccinia virus I1 protein is essential for the assembly of mature virions

Klemperer, Nancy; Ward, Joseph C.; Evans, Elizabeth L.; Traktman, Paula

doi:10.1128/jvi.71.12.9285-9294.1997

Cited by 40 publications

(11 citation statements)

References 61 publications

(85 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To identify the viral proteins co‐sedimenting with microtubules, we performed in‐gel protease digestion followed by analysis of the resulting peptides by MALDI mass spectrometry. Using this approach, we identified a number of potential vaccinia‐encoded MAPs: A10L (a structural protein), I1L and L4R (which are DNA‐binding proteins), all of which are associated with viral cores (Vanslyke and Hruby, 1994; Jensen et al ., 1996a; Klemperer et al ., 1997), and A6L which is conserved in all poxvirus genomes but is of unknown function (Figure 9).…”

Section: Resultsmentioning

confidence: 99%

“…The following antibodies were kindly provided: anti‐α‐tubulin by Dr E.Karsenti, anti‐centrin (20H5) by Professor J.L.Salisbury (Sanders and Salisbury, 1994; Paoletti et al ., 1996), anti‐Nek2 and anti‐C‐Nap1 by Professor E.Nigg (Fry et al ., 1998a,b), anti‐myc and anti‐gp27 by Dr T.Nilsson (Füllekrug et al ., 1999) and antibodies against the corresponding vaccinia proteins: A3L, A10L and L4R by Professor D.Hruby (Vanslyke and Hruby, 1994), I1L by Professor P.Traktman (Klemperer et al ., 1997), A27L (C3) by Dr M.Esteban (Rodriguez et al ., 1985), A33R, A34R and A36R (Röttger et al ., 1999). In addition, the following antibodies were obtained from commercial sources: anti‐α‐tubulin (N356) (Amersham International, UK), anti‐acetylated α‐tubulin (6‐11B‐1) (Sigma, USA), anti‐γ‐tubulin (GTU‐88; Sigma), anti‐pericentrin and anti‐TGN46 (BAbCO, USA), and rabbit IgG (Sigma).…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Vaccinia virus infection disrupts microtubule organization and centrosome function

et al. 2000

View full text Add to dashboard Cite

We examined the role of the microtubule cytoskeleton during vaccinia virus infection. We found that newly assembled virus particles accumulate in the vicinity of the microtubule-organizing centre in a microtubuleand dynein±dynactin complex-dependent fashion. Microtubules are required for ef®cient intracellular mature virus (IMV) formation and are essential for intracellular enveloped virus (IEV) assembly. As infection proceeds, the microtubule cytoskeleton becomes dramatically reorganized in a fashion reminiscent of overexpression of microtubule-associated proteins (MAPs). Consistent with this, we report that the vaccinia proteins A10L and L4R have MAP-like properties and mediate direct binding of viral cores to microtubules in vitro. In addition, vaccinia infection also results in severe reduction of proteins at the centrosome and loss of centrosomal microtubule nucleation ef®ciency. This represents the ®rst example of viral-induced disruption of centrosome function. Further studies with vaccinia will provide insights into the role of microtubules during viral pathogenesis and regulation of centrosome function.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Vaccinia virus infection disrupts microtubule organization and centrosome function

et al. 2000

View full text Add to dashboard Cite

show abstract

“…The A32 protein appears to be required at an earlier step, since repression of A32 results in the accumulation of DNA-deficient IVs (4). Also other DNAbinding proteins, such as the VV early transcription factor VETF, composed of two subunits encoded by the D6R and A8L genes, and the product of the I1L gene are needed for IV-to-IMV transition since viruses deficient in these polypeptides are blocked at the IV stage (19,20,27,29). A similar phenotype is displayed when synthesis of the two structural proteins 39K (A5L) (63) and L1R (38), present in the core and envelope, respectively, is prevented.…”

mentioning

confidence: 99%

The Major Core Protein P4a (A10L Gene) of Vaccinia Virus Is Essential for Correct Assembly of Viral DNA into the Nucleoprotein Complex To Form Immature Viral Particles

Heljasvaara¹,

Rodrı́guez²,

Risco

et al. 2001

J Virol

View full text Add to dashboard Cite

The vaccinia virus (VV) A10L gene codes for a major core protein, P4a. This polypeptide is synthesized at late times during viral infection and is proteolytically cleaved during virion assembly. To investigate the role of P4a in the virus life cycle and morphogenesis, we have generated an inducer-dependent conditional mutant (VVindA10L) in which expression of the A10L gene is under the control of the Escherichia coli lacI operator/ repressor system. Repression of the A10L gene severely impairs virus growth, as observed by both the inability of the virus to form plaques and the 2-log reduction of viral yields. This defect can be partially overcome by addition of the inducer isopropyl-␤-D-thiogalactopyranoside (IPTG). Synthesis of viral proteins other than P4a occurred, although early shutoff of host protein synthesis and expression of viral late polypeptides are clearly delayed, both in the absence and in the presence of IPTG, compared with cells infected with the parental virus. Viral DNA replication and concatemer resolution appeared to proceed normally in the absence of the A10L gene product. In cells infected with VVindA10L in the absence of the inducer virion assembly is blocked, as defined by electron microscopy. Numerous spherical immature viral particles that appear devoid of dense viroplasmic material together with highly electron-dense regular structures are abundant in VVindA10L-infected cells. These regularly spaced structures can be specifically labeled with anti-DNA antibodies as well as with a DNase-gold conjugate, indicating that they contain DNA. Some images suggest that these DNA structures enter into spherical immature viral particles. In this regard, although it has not been firmly established, it has been suggested that DNA uptake occurs after formation of spherical immature particles. Overall, our results showed that P4a and/or its cleaved products are essential for the correct assembly of the nucleoprotein complex within immature viral particles.Vaccinia virus (VV), the prototype member of the Poxviridae family, is a large DNA virus whose replication and assembly occur entirely in the cytoplasm of the host cell, in particular areas termed viral factories or virosomes (33). The linear double-stranded DNA genome has a capacity to encode over 200 polypeptides (22), of which approximately 100 are incorporated into virus particles (14). The viral genes can be divided into three classes according to their temporally regulated expression. The early genes are transcribed prior to DNA replication, while the intermediate and late genes are transcribed only during or after replication of the viral genome (33).Detailed information about VV morphogenesis has been obtained from studies by conventional electron microscopy (6, 7, 9, 21, 31, 32). Virus assembly begins within cytoplasmic viral factories with the formation of crescent-shaped membranes whose origin remains controversial. These membranes subsequently enclose granular material from the virosomes, forming spherical particles known as immature vir...

show abstract

“…The detection of and responses to viral DNA and damaged self-DNA share some common machinery. During DNA virus infection the sensing of the genome is a critical aspect of the innate immune response, but where and how this takes place, and how viruses have [66,67] Supercoiled in virion [66] Cytoplasm Human Adenovirus V (Adenovirus) Linear, dsDNA, 36 kb. Circularises upon nuclear entry [68] Protein μ, protein V, protein VII, terminal proteins.…”

Section: Discussionmentioning

confidence: 99%

Functions of DNA damage machinery in the innate immune response to DNA virus infection

Trigg

Ferguson

2015

Current Opinion in Virology

View full text Add to dashboard Cite

DNA is potently immunostimulatory, and self-DNA is packaged in the nucleus or mitochondria allowing it to remain silent to cell-intrinsic sensors. However, damaged or mislocalised self-DNA is sensed by our innate immune systems, resulting in the production of type I interferons (IFNI), chemokines and inflammatory cytokines. During DNA virus infection the detection of viral DNA genomes by pattern recognition receptors (PRRs) is essential for the initiation of IFNI responses and host defence against these pathogens. It is intriguing that a number of molecular mechanisms have been found to be common to both of these DNA-induced stress responses and this has potentially important consequences for both sides of the host/pathogen arms race.

show abstract

The vaccinia virus I1 protein is essential for the assembly of mature virions

Cited by 40 publications

References 61 publications

Vaccinia virus infection disrupts microtubule organization and centrosome function

Vaccinia virus infection disrupts microtubule organization and centrosome function

The Major Core Protein P4a (A10L Gene) of Vaccinia Virus Is Essential for Correct Assembly of Viral DNA into the Nucleoprotein Complex To Form Immature Viral Particles

Functions of DNA damage machinery in the innate immune response to DNA virus infection

Contact Info

Product

Resources

About