Mapping interactions of filamin and migfilin : mechanism of inside-out signaling integrins.

• Main Author: Lu, Lewis Zhiping.
• Other Authors: Chua Geok Lin
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Science::Biological sciences::Biophysics
• Online Access: http://hdl.handle.net/10356/55046
• Institution: Nanyang Technological University

Integrin is a transmembrane heterodimer receptor that facilitates the connection of a cell to its environment. Integrin receptors are able to bind to both the extracellular environment as well as the internal cytoskeleton of the cell. Filamin A and Talin 1 are negative and positive regulators of integrin respectively. They exert their regulatory effects by binding to the tail of beta integrins. Migfilin is a negative regulator of filamin A activity and binds to filamin A at the same site where integrin beta tail binds. Throughout the recent years, these integrin tail regulators have been the interest of research and in this study we attempt to characterize some of the binding interactions of these proteins. Filamin A immunoglobulin domain 21 (IgFLNa21) and talin1 F3 domain were expressed and purified. HNCACB and CBCA(CO)NH were carried out with IgFLNa21 for 1H-15N heteronuclear single quantum coherence (HSQC) spectrum assignment. The secondary structure of IgFLNa21 was predicted using the values of random coil and IgFLNa21 alpha carbon and beta carbon values. 1H-15N HSQC titrations were carried out for IgFLNa21 and talin1 F3 with migfilin derived peptides and integrin beta-2 peptide respectively. The titrations revealed strong and weak binding affinity of migfilin and integrin beta-2 peptides for their proteins respectively. Collectively, these results set in the foundation for further studies of the two proteins.