TY - JOUR
T1 - Peptide substrates suitable for assaying glycogen synthase kinase-3 in crude cell extracts
AU - Welsh, Gavin I.
AU - Patel, Jashmin C.
AU - Proud, Christopher G.
N1 - Funding Information:
This work was supported by a Project Grant from the Wellcome Trust. We are very grateful to Dr. Graham Bloomberg (Department of Biochemistry, University of Bristol) for synthesizing all the peptide substrates used in this study. We also express our thanks to Professor Philip Cohen, Dr. Robert Mackintosh, and Dr. Nick Morrice (MRC Protein Phosphorylation Unit, University of Dundee) for providing many of the puri®ed protein kinases used in this work.
PY - 1997/1/1
Y1 - 1997/1/1
N2 - In this study we describe the characterization and use of new peptide substrates for assaying glycogen synthase kinase-3 (GSK-3) which are based on the sequence around the single GSK-3 phosphorylation site in the translation factor eIF2B. The new peptides offer important advantages over previous substrates, which were based on the sequence around the multiple GSK-3 phosphorylation sites in glycogen synthase (GS), for the assay of GSK-3 in cell extracts. In particular, decreases in GSK-3 activity following, e.g., insulin treatment, are partially or completely masked when the GS-based peptides are used but are readily measured using the new, eIF2B-based, peptides. The new peptides, unlike those based on GS, are therefore suitable for the assay of changes in GSK-3 activity in cell extracts without the need for prior immunoprecipitation or ion-exchange chromatography.
AB - In this study we describe the characterization and use of new peptide substrates for assaying glycogen synthase kinase-3 (GSK-3) which are based on the sequence around the single GSK-3 phosphorylation site in the translation factor eIF2B. The new peptides offer important advantages over previous substrates, which were based on the sequence around the multiple GSK-3 phosphorylation sites in glycogen synthase (GS), for the assay of GSK-3 in cell extracts. In particular, decreases in GSK-3 activity following, e.g., insulin treatment, are partially or completely masked when the GS-based peptides are used but are readily measured using the new, eIF2B-based, peptides. The new peptides, unlike those based on GS, are therefore suitable for the assay of changes in GSK-3 activity in cell extracts without the need for prior immunoprecipitation or ion-exchange chromatography.
UR - http://www.scopus.com/inward/record.url?scp=0031034809&partnerID=8YFLogxK
U2 - 10.1006/abio.1996.9838
DO - 10.1006/abio.1996.9838
M3 - Article
C2 - 9025901
AN - SCOPUS:0031034809
SN - 0003-2697
VL - 244
SP - 16
EP - 21
JO - Analytical Biochemistry
JF - Analytical Biochemistry
IS - 1
ER -