1tyk
From Proteopedia
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SOLUTION STRUCTURE OF A TOXIN FROM THE TARANTULA, GRAMMOSTOLA SPATULATA, WHICH INHIBITS MECHANOSENSITIVE ION CHANNELS
Overview
Mechanosensitive channels (MSCs) play key roles in sensory processing and, have been implicated as primary transducers for a variety of cellular, responses ranging from osmosensing to gene expression. This paper presents, the first structures of any kind known to interact specifically with MSCs., GsMTx-4 and GsMtx-2 are inhibitor cysteine knot peptides isolated from, venom of the tarantula, Grammostola spatulata (Suchyna, T. M., Johnson, J., H., Hamer, K., Leykam, J. F., Gage, D. A., Clemo, H. F., Baumgarten, C., M., and Sachs, F. (2000) J. Gen. Physiol. 115, 583-598). Inhibition of, cationic MSCs by the higher affinity GsMtx-4 (K(D) approximately 500 nm), reduced cell size in swollen and hypertrophic heart cells, swelling-activated currents in astrocytes, and stretch-induced arrhythmias, in the heart. Despite the relatively low affinity, no cross-reactivity has, been found with other channels. Using two-dimensional NMR spectroscopy, we, determined the solution structure of GsMTx-4 and a lower affinity, (GsMTx-2; K(D) approximately 6 microm) peptide from the same venom. The, dominant feature of the two structures is a hydrophobic patch, utilizing, most of the aromatic residues and surrounded with charged residues. The, spatial arrangement of charged residues that are unique to GsMTx-4 and, GsMTx-2 may underlie the selectivity of these peptides.
About this Structure
1TYK is a Single protein structure of sequence from Grammostola rosea. This structure superseeds the now removed PDB entry 1LQR. Full crystallographic information is available from OCA.
Reference
Solution structure of peptide toxins that block mechanosensitive ion channels., Oswald RE, Suchyna TM, McFeeters R, Gottlieb P, Sachs F, J Biol Chem. 2002 Sep 13;277(37):34443-50. Epub 2002 Jun 24. PMID:12082099
Page seeded by OCA on Wed Nov 21 03:41:55 2007
