Recombinant Drosophila troponin-H is a dimer.

The primary sequence of Troponin-H 34 contains a single Cysteine residue. Under oxidising conditions the sulphydryl (-SH) group of each monomer forms an inter-molecular disulphide bridge (S-S) with its partner chain in the Troponin-H dimer. The crosslinked dimers have a higher apparent molecular weight than the monomers under non-reducing SDS-PAGE.

Key to lanes:

1 Reduced.
2 Oxidised.
3 After a round of oxidation and reduction.