PT  - JOURNAL ARTICLE
AU  - Laia Bassaganyas
AU  - Stephanie J. Popa
AU  - Max Horlbeck
AU  - Anupama Ashok
AU  - Sarah E. Stewart
AU  - Cristian M. Butnaru
AU  - Nathalie Brouwers
AU  - Kartoosh Heydari
AU  - Jean Ripoche
AU  - Jonathan Weissman
AU  - Randy Schekman
AU  - Vivek Malhotra
AU  - Kevin Moreau
AU  - Julien Villeneuve
TI  - New factors for protein transport identified by a genome-wide CRISPRi screen in mammalian cells
AID  - 10.1101/556746
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 556746
4099  - http://biorxiv.org/content/early/2019/02/21/556746.short
4100  - http://biorxiv.org/content/early/2019/02/21/556746.full
AB  - Protein and membrane trafficking pathways are critical for cell and tissue homeostasis. Traditional genetic and biochemical approaches have shed light on basic principles underlying these processes. However, the list of factors required for secretory pathways function remains incomplete, and mechanisms involved in their adaptation poorly understood. Here, we present a powerful strategy based on a pooled genome-wide CRISPRi screen that allowed the identification of new factors involved in protein transport. Two newly identified factors, TTC17 and CCDC157, localized along the secretory pathway and were found to interact with resident proteins of ER-Golgi membranes. In addition, we uncovered that upon TTC17 knockdown, the polarized organization of Golgi cisternae was altered, creating glycosylation defects, and that CCDC157 is an important factor for the fusion of transport carriers to the Golgi complex. In conclusion, our work identified and characterized new actors in the mechanisms of protein transport and secretion, and opens stimulating perspectives for the use of our platform in physiological and pathological contexts.