8SJ7

Crystal structure of FBF-2 (RBD+CT) in complex with compact FBE RNA

Summary for 8SJ7

• Entry DOI: 10.2210/pdb8sj7/pdb
• Descriptor: Fem-3 mRNA-binding factor 2, RNA (5'-R(*CP*UP*GP*UP*GP*AP*AP*UP*G)-3') (3 entities in total)
• Functional Keywords: puf rna binding protein, rna binding protein-rna complex, rna binding protein/rna
• Biological source: Caenorhabditis elegans; More
• Total number of polymer chains: 2
• Total formula weight: 55974.16

Authors

Qiu, C.,Hall, T.M.T. (deposition date: 2023-04-17, release date: 2023-09-27, Last modification date: 2024-04-10)

Primary citation

Qiu, C.,Zhang, Z.,Wine, R.N.,Campbell, Z.T.,Zhang, J.,Hall, T.M.T.
Intra- and inter-molecular regulation by intrinsically-disordered regions governs PUF protein RNA binding.
Nat Commun, 14:7323-7323, 2023

PubMed Abstract: PUF proteins are characterized by globular RNA-binding domains. They also interact with partner proteins that modulate their RNA-binding activities. Caenorhabditis elegans PUF protein fem-3 binding factor-2 (FBF-2) partners with intrinsically disordered Lateral Signaling Target-1 (LST-1) to regulate target mRNAs in germline stem cells. Here, we report that an intrinsically disordered region (IDR) at the C-terminus of FBF-2 autoinhibits its RNA-binding affinity by increasing the off rate for RNA binding. Moreover, the FBF-2 C-terminal region interacts with its globular RNA-binding domain at the same site where LST-1 binds. This intramolecular interaction restrains an electronegative cluster of amino acid residues near the 5' end of the bound RNA to inhibit RNA binding. LST-1 binding in place of the FBF-2 C-terminus therefore releases autoinhibition and increases RNA-binding affinity. This regulatory mechanism, driven by IDRs, provides a biochemical and biophysical explanation for the interdependence of FBF-2 and LST-1 in germline stem cell self-renewal.

PubMed: 37953271
DOI: 10.1038/s41467-023-43098-1

Experimental method

X-RAY DIFFRACTION (2.09 Å)