Rapidly transported proteins released from nerve and isolated with myelin

An in vitro preparation was used to determine if rapidly transported radiolabeled protein which is isolated with the myelin fraction of frog sciatic nerves is similar to rapidly transported radiolabeled protein released from sciatic nerves. Sciatic nerves along with their eighth and ninth dorsal root ganglia were placed in modified Warburg flasks. The center well of the flasks contained 100 microCi [3H]leucine. The preparation was incubated for 24 h, the sciatic nerve removed and the myelin isolated. The solution in which the sciatic nerve portion of the preparation incubated was removed, dialyzed and lyophilized. The radiolabeled proteins isolated from myelin and those released from the nerve were separated on 10% SDS polyacrylamide gels. Results of this separation revealed that a radiolabeled protein of 100,000 daltons was isolated with myelin and released from sciatic nerves. Incubating isolated myelin in 10 mM EDTA for 14-16 h brought about the release of a protein of 100,000 daltons.