The Odd One Out: Aabidopsis Reticulon 20 Has A Role In Lipid Biosynthesis

Kriechbaumer, V.; Maneta-Peyret, L.; Botchway, S. W.; Upson, J.; Hughes, L.; Richardson, J.; Kittelmann, M.; Moreau, P.; Hawes, C.

doi:10.1101/123679

bioRxiv · 10.1101/123679

The Odd One Out: Aabidopsis Reticulon 20 Has A Role In Lipid Biosynthesis

Kriechbaumer, V.·Maneta-Peyret, L.·Botchway, S. W.·Upson, J.·Hughes, L.·Richardson, J.·Kittelmann, M.·Moreau, P.·Hawes, C.

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Abstract

The family of reticulon proteins has been shown to be involved in a variety of functions in eukaryotic cells including tubulation of the endoplasmic reticulum (ER), formation of cell plates and primary plasmodesmata. Reticulons are integral ER membrane proteins characterised by a reticulon homology domain comprising four transmembrane domains which results in the reticulons sitting in the membrane in a W-topology. Here we report on a subgroup of reticulons with an extended N-terminal domain and in particular on arabidopsis reticulon 20. We show that reticulon 20 is located in a unique punctate pattern on the ER membrane. Its closest homologue reticulon 19 labels the whole ER. We show that mutants in RTN20 or RTN19, respectively, display a significant change in sterol composition in the roots indicating a role in lipid biosynthesis or regulation. A third homologue in this family - 3BETAHSD/D1- is localised to ER exit sites resulting in an intriguing location difference for the three proteins.

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Kriechbaumer, V., Maneta-Peyret, L., Botchway, S. W., Upson, J., Hughes, L., Richardson, J., Kittelmann, M., Moreau, P., Hawes, C.. 2017-04-07. The Odd One Out: Aabidopsis Reticulon 20 Has A Role In Lipid Biosynthesis. https://doi.org/10.1101/123679

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