Vaccinia virus infection disrupts microtubule organization and centrosome function

Abstract

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.

Infection with Replication-deficient Adenovirus Induces Changes in the Dynamic Instability of Host Cell Microtubules

“…These viruses replicate at a site near the centrosome, and the disruption of centrosome function is likely a consequence of viral replication (Ploubidou et al, 2000;Jouvenet and Wileman, 2005). Contrary to these results, the Ad-induced enhancement of MT nucleation occurred Ͻ2 h after infection and was transient.…”

“…Two other viruses, vaccinia and ASFV, have been reported to regulate MT assembly from the centrosome, but in these cases virus infection led to decreased MT nucleation and a reduction in ␥-tubulin levels at the centrosome (Ploubidou et al, 2000;Jouvenet and Wileman, 2005). These viruses replicate at a site near the centrosome, and the disruption of centrosome function is likely a consequence of viral replication (Ploubidou et al, 2000;Jouvenet and Wileman, 2005).…”

Plus-end tracking proteins, CLASPs, and a viral Akt mimic regulate herpesvirus-induced stable microtubule formation and virus spread

“…Centrosome disruption is induced by a number of viruses (24,(56)(57)(58)(59) and may represent a strategy to gain control of host MT networks or a host response to infection. Our findings demonstrate that in the absence of a centrosome, the TGN acts as an alternate MTOC in HSV-1-infected cells, with MTs emanating from the TGN rapidly becoming acetylated.…”

Characterization and Cloning of Two Isoforms of Heteroglobin, a Novel Heterodimeric Glycoprotein of the Secretoglobin-Uteroglobin Family Showing Tissue-specific and Sex Differential Expression

“…Protein bands of interest were excised and in gel digestion with trypsin performed automatically in the Progest (Genomic Solutions) as explained (47). The tryptic peptides (trim) were separated by high performance liquid chromatography (48) and sequenced in a 474 Procise peptide sequencer (Applied Biosystems).…”

“…Partial Sequencing of the Subunits HGB.A and HGB.BPurified parotid gland HGB was subjected to reducing SDS-PAGE, and the bands corresponding to the subunits HGB.A and HGB.B were processed for protein sequencing as described (47,48). As expected, amino-terminal sequencing of HGB.A elicited an identical sequence to that found in the band from parotid homogenate (see Fig.…”