6BB8

Crystal Structure of Frequency-Interacting RNA helicase (FRH)

Summary for 6BB8

• Entry DOI: 10.2210/pdb6bb8/pdb
• Descriptor: FRQ-interacting RNA helicase (1 entity in total)
• Functional Keywords: rna helicase, rna binding protein
• Biological source: Neurospora crassa
• Total number of polymer chains: 1
• Total formula weight: 124637.41

Authors

Morales, Y.,Johnson, S.J.,Olsen, K.J. (deposition date: 2017-10-17, release date: 2018-08-29, Last modification date: 2023-10-04)

Primary citation

Morales, Y.,Olsen, K.J.,Bulcher, J.M.,Johnson, S.J.
Structure of frequency-interacting RNA helicase from Neurospora crassa reveals high flexibility in a domain critical for circadian rhythm and RNA surveillance.
PLoS ONE, 13:e0196642-e0196642, 2018

PubMed Abstract: The FRH (frequency-interacting RNA helicase) protein is the Neurospora crassa homolog of yeast Mtr4, an essential RNA helicase that plays a central role in RNA metabolism as an activator of the nuclear RNA exosome. FRH is also a required component of the circadian clock, mediating protein interactions that result in the rhythmic repression of gene expression. Here we show that FRH unwinds RNA substrates in vitro with a kinetic profile similar to Mtr4, indicating that while FRH has acquired additional functionality, its core helicase function remains intact. In contrast with the earlier FRH structures, a new crystal form of FRH results in an ATP binding site that is undisturbed by crystal contacts and adopts a conformation consistent with nucleotide binding and hydrolysis. Strikingly, this new FRH structure adopts an arch domain conformation that is dramatically altered from previous structures. Comparison of the existing FRH structures reveals conserved hinge points that appear to facilitate arch motion. Regions in the arch have been previously shown to mediate a variety of protein-protein interactions critical for RNA surveillance and circadian clock functions. The conformational changes highlighted in the FRH structures provide a platform for investigating the relationship between arch dynamics and Mtr4/FRH function.

PubMed: 29718972
DOI: 10.1371/journal.pone.0196642

Experimental method

X-RAY DIFFRACTION (3.49 Å)