Next Article in Journal
Retraction: Ling, W. et al. Evaluation of Anti-Obesity Activity, Acute Toxicity, and Subacute Toxicity of Probiotic Dark Tea. Biomolecules 2018, 8(4), 99
Next Article in Special Issue
Functional Segments on Intrinsically Disordered Regions in Disease-Related Proteins
Previous Article in Journal / Special Issue
p53 Phosphomimetics Preserve Transient Secondary Structure but Reduce Binding to Mdm2 and MdmX
Article Menu
Issue 3 (March) cover image

Export Article

Open AccessArticle
Biomolecules 2019, 9(3), 84; https://doi.org/10.3390/biom9030084

Conserved Glycines Control Disorder and Function in the Cold-Regulated Protein, COR15A

1
Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, USA
2
Department of Physical Biochemistry, University of Potsdam, 14476 Potsdam, Germany
*
Authors to whom correspondence should be addressed.
Received: 15 January 2019 / Revised: 15 February 2019 / Accepted: 25 February 2019 / Published: 2 March 2019
(This article belongs to the Special Issue Intrinsically Disordered Proteins and Chronic Diseases)
  |  
PDF [2333 KB, uploaded 8 March 2019]
  |  

Abstract

Cold-regulated (COR) 15A is an intrinsically disordered protein (IDP) from Arabidopsis thaliana important for freezing tolerance. During freezing-induced cellular dehydration, COR15A transitions from a disordered to mostly α-helical structure. We tested whether mutations that increase the helicity of COR15A also increase its protective function. Conserved glycine residues were identified and mutated to alanine. Nuclear magnetic resonance (NMR) spectroscopy was used to identify residue-specific changes in helicity for wildtype (WT) COR15A and the mutants. Circular dichroism (CD) spectroscopy was used to monitor the coil–helix transition in response to increasing concentrations of trifluoroethanol (TFE) and ethylene glycol. The impact of the COR15A mutants on the stability of model membranes during a freeze–thaw cycle was investigated by fluorescence spectroscopy. The results of these experiments showed the mutants had a higher content of α-helical structure and the increased α-helicity improved membrane stabilization during freezing. Comparison of the TFE- and ethylene glycol-induced coil–helix transitions support our conclusion that increasing the transient helicity of COR15A in aqueous solution increases its ability to stabilize membranes during freezing. Altogether, our results suggest the conserved glycine residues are important for maintaining the disordered structure of COR15A but are also compatible with the formation of α-helical structure during freezing induced dehydration. View Full-Text
Keywords: COR15A; Late embryogenesis abundant; intrinsically disordered proteins; Trifluoroethanol; Nuclear magnetic resonance COR15A; Late embryogenesis abundant; intrinsically disordered proteins; Trifluoroethanol; Nuclear magnetic resonance
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Sowemimo, O.T.; Knox-Brown, P.; Borcherds, W.; Rindfleisch, T.; Thalhammer, A.; Daughdrill, G.W. Conserved Glycines Control Disorder and Function in the Cold-Regulated Protein, COR15A. Biomolecules 2019, 9, 84.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Biomolecules EISSN 2218-273X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top