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Title: Animal septins contain functional transmembrane domains
Summary Septins, a conserved family of filament-forming proteins, contribute to eukaryotic cell division, polarity, and membrane trafficking. Septins scaffold other proteins to cellular membranes, but it is not fully understood how septins associate with membranes. We identified and characterized an isoform ofCaenorhabditis elegansseptin UNC-61 that was predicted to contain a transmembrane domain (TMD). The TMD isoform is expressed in a subset of tissues where the known septins were known to act, and TMD function was required for tissue integrity of the egg-laying apparatus. We found predicted TMD-containing septins across much of opisthokont phylogeny and demonstrated that the TMD-containing sequence of a primate TMD-septin is sufficient for localization to cellular membranes. Together, our findings reveal a novel mechanism of septin-membrane association with profound implications for septin dynamics and regulation.  more » « less
Award ID(s):
2153790
PAR ID:
10577407
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
bioRxiv
Date Published:
Format(s):
Medium: X
Institution:
bioRxiv
Sponsoring Org:
National Science Foundation
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