Hi Linda,
That's an interesting problem! If you put the pseudo 2-fold axis of your
dimer along the Z-axis, then you could add 180 degrees to all rlnAngleRot
values (e.g using awk). You could then perform only local angular searches
to avoid any particles from 'flipping over'.
Alternatively, you could also subtract the contribution of the currently
refined monomer from all experimental particles, and then refine the other
monomer separately. This is along similar lines as we just did for
gamma-secretase, although there we didn't re-align subtracted particle
images anymore
(http://elifesciences.org/content/early/2015/12/01/eLife.11182).
HTH,
Sjors
> Hello Everyone,
> I am studying a flexible dimer and have refined one monomer, but I would
> wish to check whether this is a true dimer or a quasi-dimer. In order to
> do
> so I was thinking to just move the mask to the other half of the
> reference,
> but I am worried that the rotational allignment will include 180 degree
> turns, because it appears that the one half of the dimer aligns more easy
> than the other. Is there an option in relion to limit the rotations to for
> example 120 degrees? Or is there a better way to tackle this issue?
>
> Thank you,
> Linda
>
--
Sjors Scheres
MRC Laboratory of Molecular Biology
Francis Crick Avenue, Cambridge Biomedical Campus
Cambridge CB2 0QH, U.K.
tel: +44 (0)1223 267061
http://www2.mrc-lmb.cam.ac.uk/groups/scheres
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