TY - JOUR
T1 - STEF/TIAM2 mediated Rac1 activity at the nuclear envelope regulates the perinuclear actin cap
AU - Woroniuk, Anna
AU - Porter, Andrew
AU - White, Gavin
AU - Newman, Daniel
AU - Diamantopoulou, Zoi
AU - Waring, Thomas
AU - Rooney, Claire
AU - Strathdee, Douglas
AU - Marston, Daniel J
AU - Hahn, Klaus M
AU - Sansom, Owen J.
AU - Zech, Tobias
AU - Malliri, Angeliki
N1 - Funding Information:
The authors thank members of the Cell Signalling lab for their critical reading of the manuscript and Lynsey Hurley for her helpful guidance. We thank the Molecular Biology Core Facility and Advanced Imaging Facility of Cancer Research UK Manchester Institute (CRUK MI) for their assistance with sequencing, qRT-PCR and microscopy and also the BioImaging Facility at The University of Manchester for the use of their microscope suite and assistance with the AFM experiments, in particular Steven Mars-den. This work was supported by Cancer Research UK (grant number C5759/A12328), MRC (grant number MR/L007495/1) and Worldwide Cancer Research (WCR 16–0379). Work in the laboratory of K.M.H. is supported by the NIH, grant number: GM-R35GM122596. We also thank The University of Manchester who have provided us with lab space, reagents and equipment following the fire at the Paterson Building, and all those who kindly provided us with constructs, reagents and protocols for the project, particularly the Hoshino lab.
Publisher Copyright:
© 2018 The Author(s).
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2018/5/29
Y1 - 2018/5/29
N2 - The perinuclear actin cap is an important cytoskeletal structure that regulates nuclear morphology and re-orientation during front-rear polarisation. The mechanisms regulating the actin cap are currently poorly understood. Here, we demonstrate that STEF/TIAM2, a Rac1 selective guanine nucleotide exchange factor, localises at the nuclear envelope, co-localising with the key perinuclear proteins Nesprin-2G and Non-muscle myosin IIB (NMMIIB), where it regulates perinuclear Rac1 activity. We show that STEF depletion reduces apical perinuclear actin cables (a phenotype rescued by targeting active Rac1 to the nuclear envelope), increases nuclear height and impairs nuclear re-orientation. STEF down-regulation also reduces perinuclear pMLC and decreases myosin-generated tension at the nuclear envelope, suggesting that STEF-mediated Rac1 activity regulates NMMIIB activity to promote stabilisation of the perinuclear actin cap. Finally, STEF depletion decreases nuclear stiffness and reduces expression of TAZ-regulated genes, indicating an alteration in mechanosensing pathways as a consequence of disruption of the actin cap.
AB - The perinuclear actin cap is an important cytoskeletal structure that regulates nuclear morphology and re-orientation during front-rear polarisation. The mechanisms regulating the actin cap are currently poorly understood. Here, we demonstrate that STEF/TIAM2, a Rac1 selective guanine nucleotide exchange factor, localises at the nuclear envelope, co-localising with the key perinuclear proteins Nesprin-2G and Non-muscle myosin IIB (NMMIIB), where it regulates perinuclear Rac1 activity. We show that STEF depletion reduces apical perinuclear actin cables (a phenotype rescued by targeting active Rac1 to the nuclear envelope), increases nuclear height and impairs nuclear re-orientation. STEF down-regulation also reduces perinuclear pMLC and decreases myosin-generated tension at the nuclear envelope, suggesting that STEF-mediated Rac1 activity regulates NMMIIB activity to promote stabilisation of the perinuclear actin cap. Finally, STEF depletion decreases nuclear stiffness and reduces expression of TAZ-regulated genes, indicating an alteration in mechanosensing pathways as a consequence of disruption of the actin cap.
KW - A549 Cells
KW - Actin Capping Proteins/metabolism
KW - Animals
KW - COS Cells
KW - Cell Line, Tumor
KW - Cercopithecus aethiops
KW - Guanine Nucleotide Exchange Factors/metabolism
KW - Humans
KW - Mice
KW - Mice, Knockout
KW - Microfilament Proteins/metabolism
KW - Nerve Tissue Proteins/metabolism
KW - Nonmuscle Myosin Type IIB/metabolism
KW - Nuclear Envelope/metabolism
KW - Nuclear Proteins/metabolism
KW - Transcription Factors/metabolism
KW - rac1 GTP-Binding Protein/metabolism
UR - http://www.scopus.com/inward/record.url?scp=85046143852&partnerID=8YFLogxK
U2 - 10.1038/s41467-018-04404-4
DO - 10.1038/s41467-018-04404-4
M3 - Article
C2 - 29844364
SN - 2041-1723
VL - 9
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 2124
ER -
