Dumb plant virus question

[A.J.Cann]

What is/are the mechanism(s) by which endogenous expression of plant
virus coat proteins in transgenic plants result in virus resistance?
Hopefully, this will be a straightforward question to someone out
there, or is it just another example of one of thoses aspects of virus
biology we really should understand, but don't? TIA,

-- 
Dr Alan J. Cann  PhD, Department of Microbiology & Immunology,
University of Leicester, UK.
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