Particle re-extraction from non-cropped micrographs

Dear all,

I have acquired a 4Å structure of my protein using 70k particles, which I am trying to further improve. The problem is that all the downstream jobs have been performed on (F=1/2) cropped micrographs. As a result, I am trying to re-extract my good particles from the original non-cropped micrographs to have a chance of getting better resolution in my structure. However, cryosparc no longer detects them and all extraction jobs give me zero particles.
I suppose that when using as input particles found in F=1/2 micrographs, and micrographs with F=1 the coordinates are different.
Is there any way to re-extract my good particles from the non-cropped micrographs without having to go through all particle picking steps again?

Kind Regards

Hi,

Prior to re-extraction, you need to also Reassign Particles to Micrographs in order to associate your particle stack with the new source micrographs. I believe nominal particle coordinates are stored as fractions of the micrograph dimensions, so should be agnostic to downsampling.

Cheers,
Yang

I see, I will try this first then. Thank you very much for your reply.

Kind regards

@Panoskre What job type did you use to perform the cropping? Was there a common Import Movies job for the cropped and non-cropped forks of your workflow?

Hello,

For both cropped and non-cropped micrographs I used the import movies job, one with F=1/2 one with F=1.
But after running the reassign particles to micrographs job extraction works : ).

Best wishes.

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