p21(Waf1/Cip1) as a molecular sensor for BoHV-4 replication

Facoltà di Medicina Veterinaria, Dipartimento di Salute Animale, Sezione di Malattie Infettive degli Animali, Parma, Italy.
Journal of virological methods (Impact Factor: 1.78). 07/2009; 161(2):308-11. DOI: 10.1016/j.jviromet.2009.06.012
Source: PubMed


BoHV-4 replication cycle is dependent on the S-phase of the cell-cycle at the stage of viral DNA synthesis. Because p21 is a rate-limiting regulator of the G1/S-phase transition and up-regulated by DNA-damaging agents, in this study p21 expression in BoHV-4 infected cells was investigated. The p21 promoter was found to be highly activated in a dose- and time-dependent manner following BoHV-4 infection only in cells which are permissive for BoHV-4 replication. Thus p21 expression reports on BoHV-4 replication and could represent a host cell defensive response to infection-associated cellular damage.

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    • "suppressor protein p53 in response to DNA damage and has a pivotal role both in apoptosis and autophagy. Taking into account that BoHV-4 replication is dependent on the S-phase of the cell cycle and p21 is a rate-limiting regulator of the G1/S-phase transition [Capocefalo et al., 2009], we analyzed p21 expression in BoHV-4 infected cells. As expected, p21 was detected like a faster-migrating band, of 21 kDa increasing in a time-dependent manner starting from 24 h post-infection (Fig. 4A,B). "
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