|
|
||||||||
Section of Infectious Diseases, Department of Medicine, Baylor College of Medicine, Houston, TX 77030
G-CSFR cytoplasmic tyrosine (Y) residues (Y704, Y729, Y744, and Y764) become phosphorylated upon ligand binding and recruit specific Src homology 2 domain-containing proteins that link to distinct yet overlapping programs for myeloid cell survival, differentiation, proliferation, and activation. The structural basis for recruitment specificity is poorly understood but could be exploited to selectively target deleterious G-CSFR-mediated signaling events such as aberrant Stat3 activation demonstrated in a subset of acute myeloid leukemia patients with poor prognosis. Recombinant Stat3 bound to G-CSFR phosphotyrosine peptide ligands pY704VLQ and pY744LRC with similar kinetics. Testing of three models for Stat3 Src homology 2-pY ligand binding in vitro and in vivo revealed unique determinants for Stat3 recruitment and activation by the G-CSFR, the side chain of Stat3 R609, which interacts with the pY ligand phosphate group, and the peptide amide hydrogen of E638, which bonds with oxygen/sulfur within the + 3 Q/C side chain of the pY ligand when it assumes a
turn. Thus, our findings identify for the first time the structural basis for recruitment and activation of Stat3 by the G-CSFR and reveal unique features of this interaction that can be exploited to target Stat3 activation for the treatment of a subset of acute myeloid leukemia patients.
This article has been cited by other articles:
![]() |
K. Jiang, N. Hein, K. Eckert, J. Luscher-Firzlaff, and B. Luscher Regulation of the MAD1 promoter by G-CSF Nucleic Acids Res., March 1, 2008; 36(5): 1517 - 1531. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Huang, J. Qiu, S. Dong, M. S. Redell, V. Poli, M. A. Mancini, and D. J. Tweardy Stat3 Isoforms, {alpha} and , Demonstrate Distinct Intracellular Dynamics with Prolonged Nuclear Retention of Stat3 Mapping to Its Unique C-terminal End J. Biol. Chem., November 30, 2007; 282(48): 34958 - 34967. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |