IQ-motif selectivity in human IQGAP2 and IQGAP3: binding of calmodulin and myosin essential light chain


Autoria(s): Atcheson, E.; Hamilton, E.; Pathmanathan, Sevvel; Greer, Brett; Harriott, Patrick; Timson, David
Data(s)

01/10/2011

Resumo

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.

Formato

application/pdf

Identificador

http://pure.qub.ac.uk/portal/en/publications/iqmotif-selectivity-in-human-iqgap2-and-iqgap3-binding-of-calmodulin-and-myosin-essential-light-chain(43d5f956-cdfe-4eee-9d32-0e36f8dd4b2c).html

http://dx.doi.org/10.1042/BSR20100123

http://pure.qub.ac.uk/ws/files/8964123/Atcheson_BiosciRep_2011.pdf

Idioma(s)

eng

Direitos

info:eu-repo/semantics/openAccess

Fonte

Atcheson , E , Hamilton , E , Pathmanathan , S , Greer , B , Harriott , P & Timson , D 2011 , ' IQ-motif selectivity in human IQGAP2 and IQGAP3: binding of calmodulin and myosin essential light chain ' Bioscience Reports , vol 31 , no. 5 , pp. 371-379 . DOI: 10.1042/BSR20100123

Palavras-Chave #/dk/atira/pure/subjectarea/asjc/1300/1303 #Biochemistry #/dk/atira/pure/subjectarea/asjc/1300/1304 #Biophysics #/dk/atira/pure/subjectarea/asjc/1300/1307 #Cell Biology #/dk/atira/pure/subjectarea/asjc/1300/1312 #Molecular Biology
Tipo

article