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Rab18: new insights into the function of an essential protein

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Abstract

Rab18 is one of the small number of conserved Rab proteins which have been traced to the last eukaryotic common ancestor. It is found in organisms ranging from humans to trypanosomes, and localizes to multiple organelles, including most notably endoplasmic reticulum and lipid droplets. In humans, absence of Rab18 leads to a severe illness known as Warburg-Micro syndrome. Despite this evidence that Rab18 is essential, its role in cells remains mysterious. However, recent studies identifying effectors and interactors of Rab18, are now shedding light on its mechanism of action, suggesting functions related to organelle tethering and to autophagy. In this review, we examine the variety of roles proposed for Rab18 with a focus on new evidence giving insights into the molecular mechanisms it utilizes. Based on this summary of our current understanding, we identify priority areas for further research.

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Authors and Affiliations

  1. Department of Medical Biology, Near East University, Nicosia, Cyprus

    Selma Yilmaz Dejgaard

  2. Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montreal, QC, H3A 0C7, Canada

    Selma Yilmaz Dejgaard & John F. Presley

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Dejgaard, S.Y., Presley, J.F. Rab18: new insights into the function of an essential protein. Cell. Mol. Life Sci. 76, 1935–1945 (2019). https://doi.org/10.1007/s00018-019-03050-3

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