Identification of Shc Src homology 2 domain-binding peptoid-peptide hybrids.
A fluorescence anisotropy (FA) competition-based Shc Src homology 2 (SH2) domain-binding was established using the high affinity fluorescein isothiocyanate (FITC) containing peptide, FITC-NH-(CH2)4-CO-pY-Q-G-L-S-amide (8; Kd = 0.35 microM). Examination of a series of open-chain bis-alkenylamide containing peptides, prepared as ring-closing metathesis precursors, showed that the highest affinities were obtained by replacement of the original Gly residue with N alpha-substituted Gly (NSG) "peptoid" residues. This provided peptoid-peptide hybrids of the form "Ac-pY-Q-[NSG]-L-amide." Depending on the NSG substituent, certain of these hybrids exhibited up to 40-fold higher Shc SH2 domain-binding affinity than the parent Gly-containing peptide (IC50 = 248 microM) (for example, for N-homoallyl analogue 50, IC50 = 6 microM). To our knowledge, this work represents the first successful example of the application of peptoid-peptide hybrids in the design of SH2 domain-binding antagonists. These results could provide a foundation for further structural optimization of Shc SH2 domain-binding peptide mimetics.
Choi
Won Jun
WJ
Laboratory of Medicinal Chemistry, Center for Cancer Research, National Cancer Institute, National Insitutes of Health, Frederick, Maryland 21702, USA.
Kim
Sung-Eun
SE
Stephen
Andrew G
AG
Weidlich
Iwona
I
Giubellino
Alessio
A
Liu
Fa
F
Worthy
Karen M
KM
Bindu
Lakshman
L
Fivash
Matthew J
MJ
Nicklaus
Marc C
MC
Bottaro
Donald P
DP
Fisher
Robert J
RJ
Burke
Terrence R
TR
D000595:Amino Acid Sequence; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D005454:Fluorescence Polarization; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D034444:Peptoids / Q000737:chemistry / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D018909:src Homology Domains
D010455:Peptides; D034444:Peptoids; C080835:RON protein; D020794:Receptor Protein-Tyrosine Kinases; D016650:Fluorescein-5-isothiocyanate