Mouse Stbd1 is N -myristoylated and affects ER-mitochondria association and mitochondrial morphology

Starch binding domain-containing protein 1 (Stbd1) is a carbohydrate-binding protein that has been proposed to be a selective autophagy receptor for glycogen. Here, we show that mouse Stbd1 is a transmembrane endoplasmic reticulum (ER)-resident protein with the capacity to induce the formation of or...

Full description

Saved in:
Bibliographic Details
Published inJournal of cell science Vol. 130; no. 5; pp. 903 - 915
Main Authors Demetriadou, Anthi, Morales-Sanfrutos, Julia, Nearchou, Marianna, Baba, Otto, Kyriacou, Kyriacos, Tate, Edward W, Drousiotou, Anthi, Petrou, Petros P
Format Journal Article
LanguageEnglish
Published England The Company of Biologists Ltd 01.03.2017
Subjects
Online AccessGet full text

Cover

Loading…
More Information
Summary:Starch binding domain-containing protein 1 (Stbd1) is a carbohydrate-binding protein that has been proposed to be a selective autophagy receptor for glycogen. Here, we show that mouse Stbd1 is a transmembrane endoplasmic reticulum (ER)-resident protein with the capacity to induce the formation of organized ER structures in HeLa cells. In addition to bulk ER, Stbd1 was found to localize to mitochondria-associated membranes (MAMs), which represent regions of close apposition between the ER and mitochondria. We demonstrate that -myristoylation and binding of Stbd1 to glycogen act as major determinants of its subcellular targeting. Moreover, overexpression of non-myristoylated Stbd1 enhanced the association between ER and mitochondria, and further induced prominent mitochondrial fragmentation and clustering. Conversely, shRNA-mediated Stbd1 silencing resulted in an increase in the spacing between ER and mitochondria, and an altered morphology of the mitochondrial network, suggesting elevated fusion and interconnectivity of mitochondria. Our data unravel the molecular mechanism underlying Stbd1 subcellular targeting, support and expand its proposed function as a selective autophagy receptor for glycogen and uncover a new role for the protein in the physical association between ER and mitochondria.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0021-9533
1477-9137
DOI:10.1242/jcs.195263