Nucleocytoplasmic Large DNA Virus
NCLDVs are a group of large DNA viruses infecting various eukaryotic hosts, including iridoviruses, ascoviruses, poxviruses, the asfarvirus, phycodnaviruses, and the marseillevirus (Boyer et al., 2009).
From: Advances in Virus Research, 2012
Organizational Cell Biology
T. Wileman, ... P.P. Powell, in Encyclopedia of Cell Biology, 2016
The Nucleo-Cytoplasmic Large DNA Viruses Use Aggresomes to Generate Pericentriolar Factories
The nucleo-cytoplasmic large DNA viruses (NCLDV) are a family of large DNA viruses with genomes ranging from 150 kb to 1.2 MB. The family includes the poxviruses iridoviruses, African swine fever virus (ASFV), phycodnaviruses, and mimiviruses that share several conserved core genes. The NCLDV infect a wide range of hosts including mammals, arthropods, fish, and marine plankton, but all replicate and assemble in large factories located close to the nucleus at the microtubule organizing center (MTOC) (Figure 4). The factories contain viral DNA and structural proteins but lack cellular membranes and are very similar to inclusions called aggresomes that form during protein misfolding diseases (Heath et al., 2001; Wileman, 2007). Protein misfolding leads to the formation of small protein aggregates in the cytosol which are transported along microtubules by dynein motors to the MTOC where they encounter the major cellular pools of chaperones and proteasomes. If aggregates fail to fold, or exceed the proteolytic capacity of the proteasomes, they accumulate within an aggresome surrounded by mitochondria and a cage made from the vimentin filaments (Figure 4(a)). The inclusions also contain ubiquitin and a linker protein called p62/SQSTM1 that binds ubiquitin and LC3. LC3 is the major membrane protein of the autophagosome and p62 is used to remove ubiqutinated proteins from aggresomes into autophagosomes which deliver them to lysosomes for degradation. Virus factories and aggresomes share many features in common including recruitment of chaperones, proteasomes, and mitochondria and confinement within a vimentin cage. Many viruses are recognized by dynein after entering cells and delivered to the MTOC. It is possible that incoming virus capsids stimulate an aggresome response because they appear foreign or misfolded to cells (Wileman, 2007). For the NCLDV this may be beneficial and provide transport to a site for replication, for other viruses it may represent an innate immune response leading to confinement at the MTOC and degradation.
https://www.sciencedirect.com/topics/immunology-and-microbiology/nucleocytoplasmic-large-dna-virus
above. nicki minaj - chun li
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