Question: Which components of the stress granules are known to be related to motor neuron degeneration in Amyotrophic Lateral Sclerosis?

Context:
Here, we demonstrate that C-terminal ALS mutations disrupt the nuclear localizing signal (NLS) of FUS resulting in cytoplasmic accumulation in transfected cells and patient fibroblasts. FUS mislocalization is rescued by the addition of the wild-type FUS NLS to mutant proteins. We also show that oxidative stress recruits mutant FUS to cytoplasmic stress granules where it is able to bind and sequester wild-type FUS.
Recently, TDP-43 has been identified as a key protein in the pathogenesis of some cases of ALS. Although the role of TDP-43 in motor neuron degeneration is not yet known, TDP-43 has been shown to accumulate in RNA stress granules (SGs) in cell models and in spinal cord tissue from ALS patients. 
in response to oxidative stress or heat shock conditions in cultures and in vivo, the ALS-linked FUS mutants, but not wild-type FUS, assembled into perinuclear stress granules in proportion to their cytoplasmic expression levels. These findings demonstrate a potential link between FUS mutations and cellular pathways involved in stress responses that may be relevant to altered motor neuron homeostasis in ALS.
both stress granules (TIA-1 immunoreactive) and processing bodies (P-bodies; XRN-1 immunoreactive) were more prevalent in ALS motor neurons than in controls and demonstrated strong co-localization with TDP-43.
These data suggest that NFL mRNA processing is fundamentally altered in ALS spinal motor neurons to favour compartmentalization within both stress granules and P-bodies, and that TDP-43 plays a fundamental role in this process.
Transactive response DNA-binding protein 43 (TDP-43) forms abnormal ubiquitinated and phosphorylated inclusions in brain tissues from patients with amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration. TDP-43 is a DNA/RNA-binding protein involved in RNA processing, such as transcription, pre-mRNA splicing, mRNA stabilization and transport to dendrites. We found that in response to oxidative stress and to environmental insults of different types TDP-43 is capable to assemble into stress granules (SGs), ribonucleoprotein complexes where protein synthesis is temporarily arrested. 
Of note, both ALS and FTD are characterized by pathological inclusions, where some well-known SG markers localize with the ALS related proteins TDP-43 and FUS.
Mutations in fused in sarcoma (FUS), a DNA/RNA binding protein, have been associated with familial amyotrophic lateral sclerosis (fALS), which is a fatal neurodegenerative disease that causes progressive muscular weakness and has overlapping clinical and pathologic characteristics with frontotemporal lobar degeneration.
Our results indicate that mutant-FUS alters the dynamic properties of stress granules, which is consistent with a gain-of-toxic mechanism for mutant-FUS in stress granule assembly and cellular stress response.
Expression of ALS-linked FUS mutations resulted in their assembly into cytoplasmic stress granules (SGs), cellular structures that package mRNA and RNA-binding proteins during cell stress.
TDP-43 is an RNA-binding protein linked to amyotrophic lateral sclerosis (ALS) that is known to regulate the splicing, transport, and storage of specific mRNAs into stress granules
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder consisting of progressive loss of motor neurons. TDP-43 has been identified as a component of ubiquitin-immunoreactive inclusions of motor neurons in ALS.
SGs have been linked to several pathologies including inflammatory diseases, cancer, viral infection, and neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD)
PTE significantly reduced the incorporation of R521C FUS/TLS into stress granules under stress conditions.

Answer: Of note, both ALS and FTD are characterized by pathological inclusions, where some well-known SG markers localize with the ALS related proteins TDP-43 and FUS.
TDP-43 and FUS have been identified as key proteins in the pathogenesis of some cases of ALS. Although their role in motor neuron degeneration is not yet known, TDP-43 and FUS have been shown to accumulate in RNA stress granules (SGs) in cell models and in spinal cord tissue from Amyotrophic Lateral Sclerosis (ALS) patients.
Exact answer: TDP-43, FUS