Vps34 PI 3-kinase inactivation enhances insulin sensitivity through reprogramming of mitochondrial metabolism

Postdoctoral fellowships were from EU Marie Curie (PIEF-GA-2009–252916) and EMBO (ALTF 753–2010) for SA and EU Marie Curie (PIIF-GA-2009–252846) for C.C. J. M.H. was a recipient of a doctoral fellowship from Eisai UK Ltd. Work in our laboratories was supported as follows: BV: MRC [G0700755], BBSRC (BB/I007806/1 and BB/ M013278/1), CRUK (C23338/A15965), the Ludwig Institute for Cancer Research and the National Institute for Health Research (NIHR) UCL Hospitals Biomedical Research Centre; J.M.B.: NIH AG039632, GM112524. and the Albert Einstein Diabetes Research and Training Center Animal Physiology Core DK020541; E.G.: Barry Reed Cancer Research fund; G.S.: BBSRC (BB/L020874/1) and B.H.F.; S.S.: Anatomical Society of Great Britain (GT) and a Wellcome Trust Career Development Fellowship 074246/Z04/Z (S.S.); R.K.S.: Wellcome Trust (WT098498) and M.R.C. (MRC_MC_UU_12012/5); S.A. T. and L.C.: the Francis Crick Institute, which receives its core funding from CRUK (FC001187), MRC (FC001187), and the Wellcome Trust (FC001187); Y.-L.C.: the CRUK Cancer Imaging Centre in association with the MRC and DoH (England) grant C1060/ A10334, C1060/A16464, NHS funding to the NIHR BRC; B.P.: Inserm and the Fondation pour la recherche médicale

Asymmetric CLASP-dependent nucleation of noncentrosomal microtubules at the trans-Golgi network

SummaryProper organization of microtubule arrays is essential for intracellular trafficking and cell motility. It is generally assumed that most if not all microtubules in vertebrate somatic cells are formed by the centrosome. Here we demonstrate that a large number of microtubules in untreated human cells originate from the Golgi apparatus in a centrosome-independent manner. Both centrosomal and Golgi-emanating microtubules need γ-tubulin for nucleation. Additionally, formation of microtubules at the Golgi requires CLASPs, microtubule-binding proteins that selectively coat noncentrosomal microtubule seeds. We show that CLASPs are recruited to the trans-Golgi network (TGN) at the Golgi periphery by the TGN protein GCC185. In sharp contrast to radial centrosomal arrays, microtubules nucleated at the peripheral Golgi compartment are preferentially oriented toward the leading edge in motile cells. We propose that Golgi-emanating microtubules contribute to the asymmetric microtubule networks in polarized cells and support diverse processes including post-Golgi transport to the cell front

CLASP-dependent microtubule nucleation at the TGN

Proper organization of microtubule arrays is essential for intracellular trafficking and cell motility. It is generally assumed that most if not all microtubules in vertebrate somatic cells are formed by the centrosome. Here we demonstrate that a large number of microtubules in untreated human cells originate from the Golgi apparatus in a centrosome-independent manner. Both centrosomal and Golgi-emanating microtubules need γ-tubulin for nucleation. Additionally, formation of microtubules at the Golgi requires CLASPs, microtubule-binding proteins that selectively coat non-centrosomal microtubule seeds. We show that CLASPs are recruited to trans-Golgi network (TGN) at the Golgi periphery by the TGN protein GCC185. In sharp contrast to radial centrosomal arrays, microtubules nucleated at the peripheral Golgi compartment are preferentially oriented toward the leading edge in motile cells. We propose that Golgi–emanating microtubules contribute to the asymmetric microtubule networks in polarized cells and support diverse processes including post-Golgi transport to the cell front

Reduction of autophagy and increase in apoptosis correlates with a favorable clinical outcome in patients with rheumatoid arthritis treated with anti-TNF drugs

© 2019 The Author(s). Background: Autophagy has emerged as a key mechanism in the survival and function of T and B lymphocytes, and its activation was involved in apoptosis resistance in rheumatoid arthritis (RA). To investigate whether the relationship between autophagy and apoptosis may impact the response to the therapy, we analyzed ex vivo spontaneous autophagy and apoptosis in patients with RA subjected to treatment with anti-tumor necrosis factor (TNF) drugs and in vitro the effects of TNFα and anti-TNF drugs on cell fate. Methods: Peripheral blood mononuclear cells (PBMCs) from 25 RA patients treated with anti-TNF drugs were analyzed for levels of autophagy marker LC3-II by western blot and for the percentage of annexin V-positive apoptotic cells by flow cytometry. The same techniques were used to assess autophagy and apoptosis after in vitro treatment with TNFα and etanercept in both PBMCs and fibroblast-like synoviocytes (FLS) from patients with RA. Results: PBMCs from patients with RA responsive to treatment showed a significant reduction in LC3-II levels, associated with an increased apoptotic activation after 4 months of therapy with anti-TNF drugs. Additionally, the expression of LC3-II correlated with DAS28. TNFα was able to induce autophagy in a dose-dependent manner after 24 h of culture in RA PBMCs and FLS. Moreover, etanercept caused a significant reduction of autophagy and of levels of citrullinated proteins. Conclusions: Our results show how the crosstalk between autophagy and apoptosis can sustain the survival of immune cells, thus influencing RA progression. This suggests that inhibition of autophagy represents a possible therapeutic target in RA