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Enclosed the final model and problem. I use the pyrosetta.rosetta.core.pose.rna to build RNA 3D strucutre. When I check the final results, I found that 

the base part is not connected to backbone.  I want to know how to solve this problem.

Best wishes,


Post Situation: 
Tue, 2021-11-23 07:03

He! I am super surprised as I have no idea what that (ugly) setting of PyMOL that is... If you show sticks, you will likely see that the ribose ring on that odd one is open.

In the params files of rings, you see that there is a cryptic bond cutting entry —this is allows the bonding in rings to be described with a linear sequence of atoms without causing any algorithm to go round and round the ring looking for bonds. However, if the strain is too much this cut bond will fail to close.

Minimising it and its neighbours with FastRelax under cartersian settings  (minimize_bond_length true in particular) may fix it. Adding a constraint to close the ring is an option, but it may be best minimising the whole RNA double helix even at the cost of stuff moving too much.


Wed, 2021-11-24 04:05

Hello, I tried the minimize_bond_length but it didn't fix it. What do you think the solution should be? The attached files are the results of this function. Thanks in advance.  

Best wishes 


File attachments: 
Wed, 2021-12-22 04:59

In your picture is the RNA "blown up"? 
I should have said: relax.minimize_bond_angles(True) and relax.minimize_bond_length(True) result in the model "blowing up" in dihedral space —I see you have cartesian commented out and replaced with dualspace. If the RNA is blown up, then that is what happened —sorry.

If this does nothing and in the original it was not blown up and your backbone ring has indeed an unclosed CUT_BOND pair (O4' + C1') then constraining this distance may work, (cf. on adding a constrain without making a constraint file and don't forget the weight on the scorefunction). 

Mon, 2022-01-10 06:44