Here we have identified two positions, K168 and N176, in the E2 domain of Cx26 that are responsible for heterotypic compatibility. Altering these two positions together allowed for the functional heterotypic docking of Cx26 with Cx43 or Cx40, which was not previously possible. K168 and N176 are two of the four residues responsible for the formation of docking HBs in Cx26 channels. Docking HB-forming residues are critical for the formation of functional GJ channels, and have been identified as mutational hotspots across many connexin isoforms. Our findings suggest that K168 and N176 equivalent positions in Group 2 connexins are also important in docking; however their role in Group 2 specific docking mechanism has yet to be determined. While homology
models could provide valuable insight, without the support of Cx43 and Cx40 structure, it is difficult to reveal the docking mechanism in Group 2 connexins. Further studies examining the alteration of equivalent residues in different heterotypic, cross-group connexin pairs can support our claim that these two positions in the E2 domain of connexins are responsible for group-specific heterotypic compatibility.
3.8
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Curriculum Vitae
Name: Levent Berk Karademir
Post-secondary University of Western Ontario
Education and London, Ontario, Canada
Degrees: 2008-2012 H.B.Sc.
The University of Western Ontario London, Ontario, Canada
2013-2015 M.Sc (Expected Fall 2015)
Honours and Dean’s Honors List
Awards: University of Western Ontario
2008-2009, 2010-2012
Distinction
University of Western Ontario 2008-2012
Related Work Teaching Assistant
Experience The University of Western Ontario
2013-2015
Presentations:
Invited Speaker, Nexxin Forum, London, ON, 2015
Poster Presentation, London Health Research Day, London, ON, 2015
Poster Presentation, Physiology and Pharmacology Research Day, London, ON, 2014 Fourth Year Thesis Poster Presentation, London, ON, 2012