Furthermore, we used bioinformatics approach to predict the mRNA structure and found that targeting sequences of loose structure benefit to improve the virus resistance level.
Kawaoka also found a mutation in the hemagglutinin's stalk that improves the virus's stability and compensates for the other mutations, Paulson says.
Two of them improved the virus' ability to latch onto cells in the animal's upper respiratory tract.
Numerous studies have revealed that the E627K change in PB2 improves the virus's ability to replicate in mammalian cells.
Our studies indicate that serial lung passages of the WT702 virus in quail improved the virus's ability to replicate in chickens, where it was partially transmissible.
It remains to be determined whether the deletion itself is sufficient to improve the virus's ability to replicate in poultry and mice.
Several groups have tried to improve the virus spread in the tumour by modifying the tumour microenvironment to decrease the extracellular matrix (ECM) component with decorin (Choi et al, 2010), hyaluronidase (Ganesh et al, 2008), relaxin (Kim et al, 2006) and proteases such as metalloproteinase-9 (Hong et al, 2010), collagenase/dispase and trypsin (Kuriyama et al, 2000; McKee et al, 2006).
This high error rate in replication operates as a double-edged sword - improving the ability of the virus to rapidly adapt to a new host via genetic changes that aid in replication and transmission efficiency while leading to the production of defective subtypes that have reduced fitness for the current host.
As well as improving the diagnosis of cassava viruses, the development of multiplex RT-PCR protocols have revealed the common occurrence of mixed infections by CBSV and CBSUV in cassava fields of Tanzania and Kenya, which was contrary to the common belief until recently that these two viruses have existed separately.
Furthermore, the presence of organic matter has been demonstrated as improving the persistence of enteric viruses (Sobsey and Meschke 2003; Gutierrez and Nguyen 2012).
