Folding perspectives of an intrinsically disordered transactivation domain and its single mutation breaking the folding propensity

Nitin Sharma; Alexander V Fonin; Olesya G Shpironok; Sergey A Silonov; Konstantin K Turoverov; Vladimir N Uversky; Irina M Kuznetsova; Rajanish Giri

doi:10.1016/j.ijbiomac.2019.11.111

Folding perspectives of an intrinsically disordered transactivation domain and its single mutation breaking the folding propensity

Int J Biol Macromol. 2020 Jul 15:155:1359-1372. doi: 10.1016/j.ijbiomac.2019.11.111. Epub 2019 Nov 13.

Authors

Nitin Sharma¹, Alexander V Fonin², Olesya G Shpironok², Sergey A Silonov², Konstantin K Turoverov³, Vladimir N Uversky⁴, Irina M Kuznetsova⁵, Rajanish Giri⁶

Affiliations

¹ School of Basic Sciences, Indian Institute of Technology Mandi, Himachal Pradesh 175005, India.
² Laboratory of structural dynamics, stability and folding of proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.
³ Laboratory of structural dynamics, stability and folding of proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia; Peter the Great St. Petersburg Polytechnic University, Department of Biophysics, Polytechnicheskaya av. 29, St. Petersburg, Russia.
⁴ Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA; Laboratory of New Methods in Biology, Institute for Biological Instrumentation of the Russian Academy of Sciences, Pushchino, Moscow region 142290, Russia. Electronic address: vuversky@health.usf.edu.
⁵ Laboratory of structural dynamics, stability and folding of proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia. Electronic address: imk@incras.ru.
⁶ School of Basic Sciences, Indian Institute of Technology Mandi, Himachal Pradesh 175005, India; BioX Centre, Indian Institute of Technology Mandi, VPO Kamand, 175005, India. Electronic address: rajanishgiri@iitmandi.ac.in.

PMID: 31733244
DOI: 10.1016/j.ijbiomac.2019.11.111

Abstract

Transcriptional regulation is a critical facet of cellular development controlled by numerous transcription factors, among which are E-proteins (E2A, HEB, and E2-2) that play important roles in lymphopoiesis. For example, primary hematopoietic cells immortalisation is promoted by interaction of the conserved PCET motif consisting of the Leu-X-X-Leu-Leu (LXXLL) and Leu-Asp-Phe-Ser (LDFS) sequences of the transactivation domains (AD1) of E-proteins with the KIX domain of CBP/p300 transcriptional co-activators. Earlier, it was shown that the LXXLL motif is essential for the PCET-KIX interaction driven by the PCET helical transition. In this study, we analyzed the dehydration-driven gain of helicity in the conserved region (residues 11-28) of the AD1 domain of E-protein. Particularly, we showed that AD1 structure was dramatically affected by alcohols, but was insensitive to changes in pH or the presence of osmolytes sarcosine and taurine, or high polyethylene glycol (PEG) concentrations and DOPC Liposomes. These structure-forming effects of solvents were almost completely absent in the case of L21P AD1 mutant characterized by weakened interaction with KIX. This indicates that KIX interaction-induced AD1 ordering is driven by PCET motif dehydration. The L21P mutation-caused loss of molecular recognition function of AD1 is due to the mutation-induced disruption of the AD1 helical propensity.

Keywords: Intrinsically disordered proteins; PCET motif; Transactivation domain.

MeSH terms

Amino Acid Motifs
Hydrogen-Ion Concentration
Intrinsically Disordered Proteins / chemistry*
Intrinsically Disordered Proteins / genetics*
Intrinsically Disordered Proteins / metabolism
Models, Molecular
Mutation*
Protein Folding*
Transcriptional Activation*

Substances

Intrinsically Disordered Proteins