The C-terminal rod 2 fragment of filamin A forms a compact structure that can be extended

• DOI: 10.1042/bj20120361
• Publication Date: 2012-06-08T09:28:35Z
• Authors: Salla Ruskamo; Robert Gilbert; Gregor Hofmann; Pengju Jiang; Iain D. Campbell; Jari Ylänne; Ulla Pentikäinen
• Keywords: FLNA; Small-angle X-ray scattering; Fragment (logic)

Filamins are large proteins that cross-link actin filaments and connect to other cellular components. The C-terminal rod 2 region of FLNa (filamin A) mediates dimerization interacts with several transmembrane receptors intracellular signalling adaptors. SAXS (small-angle X-ray scattering) experiments were used make a model six immunoglobulin-like domain fragment the (domains 16-21). This had surprising three-branched structural arrangement, where each branch was made tightly packed two-domain pair. Peptides derived from induced more open structure fragment. Mutagenesis studies suggested these changes caused by peptides binding CD faces on domains 19 21 which displace preceding A-strands (18 20 respectively), thus opening individual pairs. A single particle cryo-EM map nine 16-24), showed relatively compact dimeric confirmed arrangement as well peptide-induced conformation changes. These findings reveal features filamin important for its interactions mechanical properties.