Symmetry breaking in homo-oligomers: the curious case of mega-hemocyanin.

Structure

Department of Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel. Electronic address:

Published: January 2015

AI Article Synopsis

  • Mega-hemocyanin is a large oxygen-carrying protein (13.5 MDa) found in snails.
  • Its structure consists of three stacked rings, with each ring composed of ten subunits.
  • Recent research using cryo-electron microscopy uncovered an unusual breaking of 5-fold symmetry in the central ring and showed that the packing of the subunits is not uniform.

Article Abstract

Mega-hemocyanin is a 13.5 MDa oxygen transporter found in snails. It is built from three stacked rings involving ten subunits each. The cryo-EM structure of the complex presented by Gatsogiannis and colleagues in this issue of Structure revealed an unexpected breaking of 5-fold symmetry in the central ring and a nonequivalent packing of the subunits.

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http://dx.doi.org/10.1016/j.str.2014.12.006DOI Listing

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