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Updated: Jun 26, 2026
07:49
Characterize Disease-related Mutants of RAF Family Kinases by Using a Set of Practical and Feasible Methods
Published on: July 17, 2019
Conformational disturbance in Abl kinase upon mutation and deregulation
Roxana E Iacob1, Teodora Pene-Dumitrescu, Jianming Zhang
1The Barnett Institute and Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA.
Summary
Hydrogen exchange mass spectrometry revealed crucial protein dynamics in Abl kinase regulation. Conformational changes were observed in some imatinib-resistant mutants, highlighting allosteric interactions
Area of Science:
- Biochemistry and Molecular Biology
- Structural Biology
- Pharmacology
Background:
- Protein dynamics are critical for protein function, yet methods to study them are limited.
- Aberrant proteins like Bcr-Abl, implicated in chronic myelogenous leukemia, exhibit altered dynamics and conformation.
- The conformational impact of imatinib resistance mutations in Abl kinase and allosteric regulation remain poorly understood.
Purpose of the Study:
- To investigate the conformational dynamics of wild-type Abl kinase and its mutants using Hydrogen exchange mass spectrometry (HX MS).
- To compare the solution structures of Abl with nonmyristoylated and imatinib-resistant forms (T315I, Y253H, E255V).
- To elucidate the role of allosteric interactions in Abl kinase regulation.
Main Methods:
- Hydrogen exchange mass spectrometry (HX MS) was employed to compare protein conformations.
- Wild-type Abl was analyzed alongside a nonmyristoylated form and three clinically relevant imatinib resistance mutants (T315I, Y253H, E255V).
- HX MS data identified HX-resistant regions indicative of stable protein structures.
Main Results:
- A HX-resistant core was identified at the SH2 and kinase domain interface, crucial for the down-regulated state.
- Demyristoylation induced conformational changes consistent with SH2 domain movement during activation.
- The T315I mutant showed conformational changes, while Y253H and E255V mutants exhibited no significant alterations in conformation.
Conclusions:
- Allosteric interactions and conformational changes significantly influence Abl kinase regulation in solution.
- HX MS is a valuable tool for studying protein dynamics and conformational changes.
- Understanding these dynamics provides mechanistic insights into protein function and drug resistance.
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