TY  - JOUR
A1  - Yadav, Preeti
A1  - Selvaraj, Bhuvaneish T.
A1  - Bender, Florian L. P.
A1  - Behringer, Marcus
A1  - Moradi, Mehri
A1  - Sivadasan, Rajeeve
A1  - Dombert, Benjamin
A1  - Blum, Robert
A1  - Asan, Esther
A1  - Sauer, Markus
A1  - Julien, Jean-Pierre
A1  - Sendtner, Michael
T1  - Neurofilament depletion improves microtubule dynamics via modulation of Stat3/stathmin signaling
JF  - Acta Neuropathologica
N2  - In neurons, microtubules form a dense array within axons, and the stability and function of this microtubule network is modulated by neurofilaments. Accumulation of neurofilaments has been observed in several forms of neurodegenerative diseases, but the mechanisms how elevated neurofilament levels destabilize axons are unknown so far. Here, we show that increased neurofilament expression in motor nerves of pmn mutant mice, a model of motoneuron disease, causes disturbed microtubule dynamics. The disease is caused by a point mutation in the tubulin-specific chaperone E (Tbce) gene, leading to an exchange of the most C-terminal amino acid tryptophan to glycine. As a consequence, the TBCE protein becomes instable which then results in destabilization of axonal microtubules and defects in axonal transport, in particular in motoneurons. Depletion of neurofilament increases the number and regrowth of microtubules in pmn mutant motoneurons and restores axon elongation. This effect is mediated by interaction of neurofilament with the stathmin complex. Accumulating neurofilaments associate with stathmin in axons of pmn mutant motoneurons. Depletion of neurofilament by Nefl knockout increases Stat3-stathmin interaction and stabilizes the microtubules in pmn mutant motoneurons. Consequently, counteracting enhanced neurofilament expression improves axonal maintenance and prolongs survival of pmn mutant mice. We propose that this mechanism could also be relevant for other neurodegenerative diseases in which neurofilament accumulation and loss of microtubules are prominent features.
KW  - Amyotrophic-lateral-sclerosis
KW  - Transgenic mice
KW  - Mouse model
KW  - Alzheimers disease
KW  - Neurofilament
KW  - Progressive motor neuronopathy
KW  - Axonal transport
KW  - Intermediate filaments
KW  - Motoneuron disease
KW  - Lacking neurofilaments
KW  - Missense mutation
KW  - Axon degeneration
KW  - Microtubules
KW  - Stathmin
KW  - Stat3
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-188234
VL  - 132
IS  - 1
ER  - 
TY  - JOUR
A1  - Thangaraj Selvaraj, Bhuvaneish
A1  - Frank, Nicolas
A1  - Bender, Florian L. P.
A1  - Asan, Esther
A1  - Sendtner, Michael
T1  - Local axonal function of STAT3 rescues axon degeneration in the pmn model of motoneuron disease
JF  - The Journal of Cell Biology
N2  - Axonal maintenance, plasticity, and regeneration are influenced by signals from neighboring cells, in particular Schwann cells of the peripheral nervous system. Schwann cells produce neurotrophic factors, but the mechanisms by which ciliary neurotrophic factor (CNTF) and other neurotrophic molecules modify the axonal cytoskeleton are not well understood. In this paper, we show that activated signal transducer and activator of transcription-3 (STAT3), an intracellular mediator of the effects of CNTF and other neurotrophic cytokines, acts locally in axons of motoneurons to modify the tubulin cytoskeleton. Specifically, we show that activated STAT3 interacted with stathmin and inhibited its microtubule-destabilizing activity. Thus, ectopic CNTF-mediated activation of STAT3 restored axon elongation and maintenance in motoneurons from progressive motor neuronopathy mutant mice, a mouse model of motoneuron disease. This mechanism could also be relevant for other neurodegenerative diseases and provide a target for new therapies for axonal degeneration.
KW  - Schwann cells
KW  - transcription-3 (STAT3)
KW  - ciliary neurotrophic factor (CNTF)
KW  - axonal degeneration
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-154675
VL  - 199
IS  - 3
SP  - 437
EP  - 451
ER  -