Abstract
The interaction of actin and rabbit subfragment 1 has been reexamined by using a carbodiimide cross-linking reagent. A major doublet with an apparent MW of 134,000 as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis has been identified. A minor product of much higher MW is also formed. Stoichiometry determinations using [3H]actin and [14C]subfragment 1 indicate that the major doublet is a 1:1 complex of actin and subfragment 1. This result confirms that reported by Sutoh.