FtsZ Protofilament Curvature Is the Opposite of Tubulin Rings.

Journal Article (Journal Article)

FtsZ protofilaments (pfs) form the bacterial cytokinetic Z ring. Previous work suggested that a conformational change from straight to curved pfs generated the constriction force. In the simplest model, the C-terminal membrane tether is on the outside of the curved pf, facing the membrane. Tubulin, a homologue of FtsZ, also forms pfs with a curved conformation. However, it is well-established that tubulin rings have the C terminus on the inside of the ring. Could FtsZ and tubulin rings have the opposite curvature? In this study, we explored the FtsZ curvature direction by fusing large protein tags to the FtsZ termini. Thin section electron microscopy showed that the C-terminal tag was on the outside, consistent with the bending pf model. This has interesting implications for the evolution of tubulin. Tubulin likely began with the curvature of FtsZ, but evolution managed to reverse direction to produce outward-curving rings, which are useful for pulling chromosomes.

Full Text

Duke Authors

Cited Authors

  • Housman, M; Milam, SL; Moore, DA; Osawa, M; Erickson, HP

Published Date

  • July 26, 2016

Published In

Volume / Issue

  • 55 / 29

Start / End Page

  • 4085 - 4091

PubMed ID

  • 27368355

Pubmed Central ID

  • PMC5310649

Electronic International Standard Serial Number (EISSN)

  • 1520-4995

Digital Object Identifier (DOI)

  • 10.1021/acs.biochem.6b00479


  • eng

Conference Location

  • United States