Chemical Biology And Endomembrane Trafficking In Plants

Journal Article · Fri Apr 01 00:00:00 EDT 2016 · FASEB Journal

DOI:https://doi.org/10.1096/fasebj.30.1_supplement.253.1· OSTI ID:1786665

Hicks, Glenn R. ^[1]; Zhang, Chunhua ^[1]; Van de Ven, Wilhelmina ^[1]; Li, Ruixi ^[1]; Raikhel, Natasha ^[1]

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1. Center for Plant Cell Biology &, Dept of Botany and Plant Sciences Univ. of California, Riverside Riverside CA

Endomembrane trafficking is essential for coordinated growth and development in plants and response to environment. In particular, key plasma membrane proteins such as PIN auxin transporters and the BRI1 brassinosteroid receptor translocate dynamically between the endosomes and plasma membrane. We utilized a previously published large‐scale chemical library screening approach in which we identified small molecules that inhibited pollen germination or tube growth. This tip growth requires exocytosis, endocytosis and other endomembrane trafficking processes

We then identified groups of small molecules that affect trafficking of PIN auxin transporters and other plasma membrane proteins in Arabidopsis roots. One of these compounds (ES2) targets the essential EXO70A1 component of the exocyst complex in Arabidopsis which is necessary for normal development. In Arabidopsis, there are 23 EXO70 genes (in mammals and yeast they are low copy number) where, among other roles, they appear to be involved in autophagy, cell division and pathogen responses. ES2 targets the exocyst complex in plants as well as mammals including humans where defective recycling/exocytosis have been correlated with disease. To our knowledge, ES2 is the first bioactive compound known to have this specificity. To examine exocytosis and its regulation in more detail, we have examined exo70 mutants, generated EXO70A1 structural data and are examining additional small molecules that may affect recycling/exocytosis.

Support or Funding Information

Acknowledgement: This work was supported by the US Department of Energy DE‐FG02‐02ER15295 (GRH, NVR).

• Sponsoring Organization: USDOE
• Grant/Contract Number: FG02-02ER15295
• OSTI ID: 1786665
• Journal Information: FASEB Journal, Journal Name: FASEB Journal Journal Issue: S1 Vol. 30; ISSN 0892-6638
• Publisher: FASEB
• Country of Publication: United States
• Language: English