title: p-NN'-phenylenebismaleimide, a specific cross-linking agent for F-actin.
abstract: Covalent cross-links can be inserted between the subunits of F-actin by using p-NN'-phenylenebismaleimide. Cross-linking reaches its maximum value when one molecule of reagent has reacted with each actin subunit. p-NN'-Phenylenebismaleimide reacts initially with a cysteine residue on one subunit, the slower cross-linking reaction involving a lysine residue on a neighbouring subunit. Hydrolysis of the actin-bound reagent limits the extent of cross-linking. Quantitative analysis of the amounts of cross-linked oligomers seen on polyacrylamide gels containing sodium dodecyl sulphate suggests that neither the binding of the reagent to actin nor the formation of cross-links introduces strain into the structure. The cross-links do not join together different F-actin filaments, and evidence is presented that suggests that the cross-links join subunits of the same long-pitched helix.
mesh_terms: D000199:Actins; D055598:Chemical Phenomena; D002621:Chemistry; D003545:Cysteine; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D008301:Maleimides; D013696:Temperature
chemical_list: D000199:Actins; D008301:Maleimides; D003545:Cysteine