Structural disorder within paramyxoviral nucleoproteins

Area of Science:

• Virology
• Structural Biology
• Molecular Biology

Background:

• Paramyxoviruses, including measles virus (MeV), Nipah virus (NiV), and Hendra virus (HeV), possess nucleoprotein (N) structures with significant intrinsic disorder.
• The C-terminal domain of the N protein (NTAIL) is intrinsically disordered and undergoes a transition upon binding to the phosphoprotein's X domain (XD).

Purpose of the Study:

• To review available data on structural disorder in paramyxovirus nucleoproteins.
• To describe the molecular mechanisms of the disorder-to-order transition in NTAIL-XD complexes.
• To discuss the functional implications of this structural disorder for viral replication.

Main Methods:

• Review of existing structural and biophysical data.
• Analysis of molecular mechanisms governing protein-protein interactions.
• Discussion of structure-function relationships in viral replication machinery.

Main Results:

• Nucleoproteins from MeV, NiV, and HeV exhibit substantial structural disorder.
• The NTAIL domain transitions from a disordered to an ordered state upon binding to XD, forming "fuzzy" complexes with persistent flexibility.
• Disordered regions in viral proteins contribute to the promiscuity and reach of the replication machinery.

Conclusions:

• Structural disorder in paramyxovirus nucleoproteins is a key feature influencing viral processes.
• The flexible nature of NTAIL-XD complexes plays a role in viral transcription and replication.
• Understanding these "fuzzy" complexes offers insights into paramyxovirus pathogenesis and potential therapeutic targets.