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Updated: Dec 31, 2025

Nuclear Magnetic Resonance Spectroscopy for the Identification of Multiple Phosphorylations of Intrinsically Disordered Proteins
12:47

Nuclear Magnetic Resonance Spectroscopy for the Identification of Multiple Phosphorylations of Intrinsically Disordered Proteins

Published on: December 27, 2016

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NMR resonance assignments for the active and inactive conformations of the small G protein RalA

Arooj Shafiq1,2, Louise J Campbell1, Darerca Owen1

  • 1Department of Biochemistry, 80, Tennis Court Road, Cambridge, CB2 1GA, UK.

Biomolecular NMR Assignments
|January 10, 2020
PubMed

Insights

Researchers have mapped the structure of RalA, a protein involved in cancer, in both active and inactive states. These findings aid in developing new cancer drugs by enabling NMR-based screening.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Structural Biology

Background:

  • Ral proteins (RalA and RalB) are small G proteins in the Ras family.
  • They regulate key cellular processes including exocytosis, endocytosis, and mitochondrial fission.
  • Aberrant Ral protein activity is linked to tumor development.

Purpose of the Study:

  • To determine the 1H, 15N, and 13C resonance assignments of RalA in its active, GTP-bound form.
  • To obtain backbone assignments for RalA in its inactive, GDP-bound state.
  • To provide structural insights into RalA's nucleotide-dependent conformational changes.

Main Methods:

  • Nuclear Magnetic Resonance (NMR) spectroscopy was used to assign resonances.
  • Assignments were performed on RalA bound to the GTP analogue GMPPNP (active form).
  • Backbone assignments were also obtained for GDP-bound RalA (inactive form).

Main Results:

  • Complete resonance assignments for active, GMPPNP-bound RalA were achieved.
  • Backbone assignments were successfully obtained for inactive, GDP-bound RalA.
  • The study provides insights into the conformational dynamics of RalA's switch regions upon nucleotide exchange.

Conclusions:

  • The reported assignments offer valuable structural data for RalA.
  • These assignments are crucial for understanding RalA's function in cellular signaling.
  • The data will facilitate NMR-based drug screening for cancer therapies targeting RalA.
Keywords:
G ProteinGtpaseRalRasSignalling

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