plant viral receptors

[Ed Rybicki]

> can someone put me in the picture how conserved surface structure sequence at
> the a.a. level is in plant viruses ?

Not very, would be the quick and flippant answer: various people have
looked at (for example) the sequence similarity of coat proteins of
spherical T=3 virions and filamentous and rodlike virions, and the answer
is that although structure is conserved - in broad terms, meaning beta-
barrel structure(s), and roughly similar tertiary structures for
the long virus CPs - sequence is not, except among closely related
viruses.  There is no constraint on plant virus capsid proteins for
receptor sequence recognition - or pressure to evolve away from antibody
recognition - EXCEPT where it comes to vectoring, where there needs to be
some sequence conservation for recognition of (for example) aphid gut wall
receptors.  Fields 2nd Edn. has a nice canned history of plant virus
capsid and other sequences (in chapter on Virus Evolution).

  ____________________________________________________________________
 | Ed Rybicki, PhD             |       "Lord, won't you buy me        |
 | (ed at micro.uct.ac.za)        |                                      |
 | Dept Microbiology           |         A Mer-ce-des Benz..."        |
 | University of Cape Town     |                                      |
 | Private Bag, Rondebosch     |                                      |
 | 7700, South Africa          |           - Janis Joplin             |
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