TY - JOUR
T1 - Golgi fragmentation in pmn mice is due to a defective ARF1/TBCE cross-talk that coordinates COPI vesicle formation and tubulin polymerization
AU - Bellouze, Sarah
AU - Schäfer, Michael K
AU - Buttigieg, Dorothée
AU - Baillat, Gilbert
AU - Rabouille, Catherine
AU - Haase, Georg
N1 - © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected].
PY - 2014/11/15
Y1 - 2014/11/15
N2 - Golgi fragmentation is an early hallmark of many neurodegenerative diseases but its pathophysiological relevance and molecular mechanisms are unclear. We here demonstrate severe and progressive Golgi fragmentation in motor neurons of progressive motor neuronopathy (pmn) mice due to loss of the Golgi-localized tubulin-binding cofactor E (TBCE). Loss of TBCE in mutant pmn and TBCE-depleted motor neuron cultures causes defects in Golgi-derived microtubules, as expected, but surprisingly also reduced levels of COPI subunits, decreased recruitment of tethering factors p115/GM130 and impaired Golgi SNARE-mediated vesicle fusion. Conversely, ARF1, which stimulates COPI vesicle formation, enhances the recruitment of TBCE to the Golgi, increases polymerization of Golgi-derived microtubules and rescues TBCE-linked Golgi fragmentation. These data indicate an ARF1/TBCE-mediated cross-talk that coordinates COPI formation and tubulin polymerization at the Golgi. We conclude that interruption of this cross-talk causes Golgi fragmentation in pmn mice and hypothesize that similar mechanisms operate in human amyotrophic lateral sclerosis and spinal muscular atrophy.
AB - Golgi fragmentation is an early hallmark of many neurodegenerative diseases but its pathophysiological relevance and molecular mechanisms are unclear. We here demonstrate severe and progressive Golgi fragmentation in motor neurons of progressive motor neuronopathy (pmn) mice due to loss of the Golgi-localized tubulin-binding cofactor E (TBCE). Loss of TBCE in mutant pmn and TBCE-depleted motor neuron cultures causes defects in Golgi-derived microtubules, as expected, but surprisingly also reduced levels of COPI subunits, decreased recruitment of tethering factors p115/GM130 and impaired Golgi SNARE-mediated vesicle fusion. Conversely, ARF1, which stimulates COPI vesicle formation, enhances the recruitment of TBCE to the Golgi, increases polymerization of Golgi-derived microtubules and rescues TBCE-linked Golgi fragmentation. These data indicate an ARF1/TBCE-mediated cross-talk that coordinates COPI formation and tubulin polymerization at the Golgi. We conclude that interruption of this cross-talk causes Golgi fragmentation in pmn mice and hypothesize that similar mechanisms operate in human amyotrophic lateral sclerosis and spinal muscular atrophy.
U2 - 10.1093/hmg/ddu320
DO - 10.1093/hmg/ddu320
M3 - Article
C2 - 24951541
SN - 0964-6906
VL - 23
SP - 5961
EP - 5975
JO - Human Molecular Genetics
JF - Human Molecular Genetics
IS - 22
ER -