TY - JOUR
T1 - Septin 9 has Two Polybasic Domains Critical to Septin Filament Assembly and Golgi Integrity
AU - Omrane, Mohyeddine
AU - Camara, Amanda Souza
AU - Taveneau, Cyntia
AU - Benzoubir, Nassima
AU - Tubiana, Thibault
AU - Yu, Jinchao
AU - Guérois, Raphaël
AU - Samuel, Didier
AU - Goud, Bruno
AU - Poüs, Christian
AU - Bressanelli, Stéphane
AU - Garratt, Richard Charles
AU - Thiam, Abdou Rachid
AU - Gassama-Diagne, Ama
PY - 2019/3/29
Y1 - 2019/3/29
N2 - Septins are GTP-binding proteins involved in several membrane remodeling mechanisms. They associate with membranes, presumably using a polybasic domain (PB1)that interacts with phosphoinositides (PIs). Membrane-bound septins assemble into microscopic structures that regulate membrane shape. How septins interact with PIs and then assemble and shape membranes is poorly understood. Here, we found that septin 9 has a second polybasic domain (PB2)conserved in the human septin family. Similar to PB1, PB2 binds specifically to PIs, and both domains are critical for septin filament formation. However, septin 9 membrane association is not dependent on these PB domains, but on putative PB-adjacent amphipathic helices. The presence of PB domains guarantees protein enrichment in PI-contained membranes, which is critical for PI-enriched organelles. In particular, we found that septin 9 PB domains control the assembly and functionality of the Golgi apparatus. Our findings offer further insight into the role of septins in organelle morphology.
AB - Septins are GTP-binding proteins involved in several membrane remodeling mechanisms. They associate with membranes, presumably using a polybasic domain (PB1)that interacts with phosphoinositides (PIs). Membrane-bound septins assemble into microscopic structures that regulate membrane shape. How septins interact with PIs and then assemble and shape membranes is poorly understood. Here, we found that septin 9 has a second polybasic domain (PB2)conserved in the human septin family. Similar to PB1, PB2 binds specifically to PIs, and both domains are critical for septin filament formation. However, septin 9 membrane association is not dependent on these PB domains, but on putative PB-adjacent amphipathic helices. The presence of PB domains guarantees protein enrichment in PI-contained membranes, which is critical for PI-enriched organelles. In particular, we found that septin 9 PB domains control the assembly and functionality of the Golgi apparatus. Our findings offer further insight into the role of septins in organelle morphology.
KW - Cell Biology
KW - Functional Aspects of Cell Biology
KW - Membrane Architecture
KW - Molecular Interaction
UR - http://www.scopus.com/inward/record.url?scp=85065305734&partnerID=8YFLogxK
U2 - 10.1016/j.isci.2019.02.015
DO - 10.1016/j.isci.2019.02.015
M3 - Article
AN - SCOPUS:85065305734
VL - 13
SP - 138
EP - 153
JO - iScience
JF - iScience
SN - 2589-0042
ER -