Immunochemical Probing of the Functional Role of the 238–246 and 567–574 Sequences of Myosin Heavy Chain

Edna Blotnick, Carl Miller, Ute Groschel‐Stewart, Andras Muhlrad*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Scopus citations

Abstract

Polyclonal site‐directed peptide antibodies were raised against the 567–574 and 238–246 sequences of the rabbit skeletal muscle myosin heavy chain. These sequences, which are located in the subfragment 1 (S1) segment of myosin, have been implicated by former studies in actin and nucleotide binding of the molecule and in the communication between the two binding sites. The antibodies obtained from rabbit sera were found to be conformation‐sensitive since they specifically reacted with S1 in solid‐phase binding assay but not in Western blot. The binding of both antibodies to S1 was strongly inhibited by actin. The antibody against the 567–574 sequence, Ab567–574, moderately decreased the binding of S1 to actin filaments in rigor but not in the weakly–attached state, while Ab238–246 did not influence the binding of S1 to actin under either conditions. Both antibodies inhibited the actin activation of the MgATPase of S1 but did not affect MgATPase without actin or the Ca‐ and K(EDTA)‐activated ATPase activities of S1. The sliding velocity of actin filaments in the in vitro motility assays were also reduced in the presence of the antibodies. Ab567–574 had especially strong inhibitory effect on the movement of actin filaments. The results indicate that the binding of antibodies may induce conformational changes, which propagate in the S1 structure, perturb the coupling between the binding sites and impair the motor function of myosin.

Original languageEnglish
Pages (from-to)235-240
Number of pages6
JournalEuropean Journal of Biochemistry
Volume232
Issue number1
DOIs
StatePublished - Aug 1995

Keywords

  • actin
  • myosin
  • myosin subfragment 1
  • polyclonal antibodies

Fingerprint

Dive into the research topics of 'Immunochemical Probing of the Functional Role of the 238–246 and 567–574 Sequences of Myosin Heavy Chain'. Together they form a unique fingerprint.

Cite this