This paper appears to clarify a couple of things:
Annals of Neurology, accepted for publicationA novel monoclonal antibody reveals a conformational alteration shared by amyotrophic lateral sclerosis-linked SOD1 mutantsT. Fujisawa, K. Homma, N. Yamaguchi, H. Kadowaki, N. Tsuburaya, I. Naguro, A. Matsuzawa, K. Takeda, Y. Takahashi, J. Goto, S. Tsuji MD, H. Ni****oh and H. Ichijo
AbstractObjective:Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that is characterized by the selective loss of upper and lower motoneurons. Although more than 100 different Cu, Zn superoxide dismutase (SOD1) mutations are identified in ALS patients, it remains controversial whether all of them are disease-causative mutations. Therefore, it is necessary to develop the molecular mechanism-based diagnosis and treatment of ALS caused by SOD1 mutations.
Methods: We previously reported that three pathogenic mutations of SOD1 cause chronic endoplasmic reticulum (ER) stress by inducing the binding of SOD1 to Derlin-1, a component of the ER homeostatic machinery. Here, we systematically analyzed 132 SOD1 mutants and found that most have a constitutively exposed Derlin-1-binding region (DBR) that is occluded in the wild-type protein. To develop the novel molecular mechanism-based antibody that can specifically recognize the aberrant structure of toxic SOD1 mutants, we generated the monoclonal antibody against the DBR.
Results: MS785, a monoclonal antibody generated against the DBR, distinguished most of ALS-causative SOD1 mutants from both wild-type and non-toxic mutants. Moreover, MS785 recognized endogenous SOD1 in B-lymphocytes derived from 14 ALS patients carrying SOD1 mutations but not from 11 healthy controls.
Interpretation: This is the first study to address the common property of all ALS-causative SOD1 mutants. MS785 is the first molecular mechanism-based antibody that was shown to be able to distinguish ALS-linked toxic SOD1 mutants from both wild-type and non-toxic mutants. MS785 may thus become an innovative tool for the diagnosis of ALS.
Web LinkFurthermore, it may be noted that MS785 also is reported to recognize WT SOD1 that has been provoked to assume a mutant-like conformation by serum-starvation of HEK293 cells. It is noted that serum-starvation may be approximated to ER-stress by nutrient deprivation.
Provided that this finding is true it implies that mutant SOD1 causes FALS by inducing ER-stress, plus that WT SOD1 contributes to SALS by assuming a mutant-like conformation during ER-stress. This in turn implies that the only thing you have to do in order to get ALS is to somehow achieve a critical level of ER-stress in the cells that are relevant to the disease and the rest of the story is essentially a self-playing piano.
See also
Nature Reviews Neurology 8, 414 (August 2012) | doi:10.1038/nrneurol.2012.130.
See also previously posted paper:
Wild-type and mutant SOD1 share an aberrant conformation and a common pathogenic pathway in ALS.
The old chicken and egg discussion between me and ENV may consequently have been resolved.
Don't just ask what scientists can do to speed up the solution for ALS or when they will do it, instead ask yourself what you can do right now to solve ALS asap.