The ta-siRNAs are methylated at the 3′ ends by HEN1 and then guided by an AGO protein (AGO1 and possibly another AGO protein) to their targets for cleavage [20, 86].
But today an AGO spokeswoman said: "After a number of complaints, we carefully considered whether Stuart Kerner's sentence could be referred to the Court of Appeal for being too low - as part of the 'unduly lenient sentence scheme'.
One strand of the small dsRNA processed by Dicer, called a guide strand, is loaded onto an AGO protein to form RISC, which recognizes a target sequence that is usually embedded within the 3′ UTR region of a target mRNA in the P-body (Gregory et al., 2005; Liu et al., 2005; Eulalio et al., 2007).
However, only one of these examples with ago1 and CMV, provides evidence that an AGO protein protects against a fully virulent virus [12].
Presumably, the level at which a specific viral siRNA accumulates in vivo will largely depend on whether it can be efficiently recruited into an AGO complex.
In addition, as mentioned earlier, recruitment of viral siRNAs into an AGO protein lacking a robust "slicer" activity could also render the siRNAs inactive in directing target cleavage.
