期刊
BIOSCIENCE REPORTS
卷 31, 期 5, 页码 371-379出版社
PORTLAND PRESS LTD
DOI: 10.1042/BSR20100123
关键词
alpha-helical peptide; calcium-dependent interaction; IQ-motif-containing GTPase-activating protein (IQGAP); IQ-motif; myosin essential light chain; native gel electrophoresis
资金
- Biochemical Society
- Biotechnology and Biological Sciences Research Council, U.K. [BB/D000394/1]
- Wellcome Trust, UK
- Department of Employment and Learning, Northern Ireland
- Queen's University, Belfast
- BBSRC [BB/D000394/1] Funding Source: UKRI
- Biotechnology and Biological Sciences Research Council [BB/D000394/1] Funding Source: researchfish
The IQGAP [IQ-motif-containing GAP (GTPase-activating protein)] family members are eukaryotic proteins that act at the interface between cellular signalling and the cytoskeleton. As such they collect numerous inputs from a variety of signalling pathways. A key binding partner is the calcium-sensing protein CaM (calmodulin). This protein binds mainly through a series of IQ-motifs which are located towards the middle of the primary sequence of the IQGAPs. In some IQGAPs, these motifs also provide binding sites for CaM-like proteins such as myosin essential light chain and S100B. Using synthetic peptides and native gel electrophoresis, the binding properties of the IQ-motifs from human IQGAP2 and IQGAP3 have been mapped. The second and third IQ-motifs in IQGAP2 and all four of the IQ-motifs of IQGAP3 interacted with CaM in the presence of calcium ions. However, there were differences in the type of interaction: while some IQ-motifs were able to form complexes with CaM which were stable under the conditions of the experiment, others formed more transient interactions. The first IQ-motifs from IQGAP2 and IQGAP3 formed transient interactions with CaM in the absence of calcium and the first motif from IQGAP3 formed a transient interaction with the myosin essential light chain MIc1sa. None of these IQ-motifs interacted with S100B. Molecular modelling suggested that all of the IQ-motifs, except the first one from IQGAP2 formed alpha-helices in solution. These results extend our knowledge of the selectivity of IQ-motifs for CaM and related proteins.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据