Intracellular localization and splicing regulation of FUS/TLS are variably affected by amyotrophic lateral sclerosis-linked mutations.
TLS (translocated in liposarcoma), also known as FUS (fused in sarcoma), is an RNA/DNA-binding protein that plays regulatory roles in transcription, pre-mRNA splicing and mRNA transport. Mutations in TLS are responsible for familial amyotrophic lateral sclerosis (ALS) type 6. Furthermore, TLS-containing intracellular inclusions are found in polyglutamine diseases, sporadic ALS, non-SOD1 familial ALS and a subset of frontotemporal lobar degeneration, indicating a pathological significance of TLS in a wide variety of neurodegenerative diseases. Here, we identified TLS domains that determine intracellular localization of the murine TLS. Among them, PY-NLS located in the C-terminus is a strong determinant of intracellular localization as well as splicing regulation of an E1A-derived minigene. Disruption of PY-NLS promoted the formation of cytoplasmic granules that were partially overlapped with stress granules and P-bodies. Some of the ALS-linked mutations altered both intracellular localization and splicing regulation of TLS, while most mutations alone did not affect splicing regulation. However, phospho-mimetic substitution of Ser505 (or Ser513 in human) could enhance the effects of ALS mutations, highlighting interplay between post-translational modification and ALS-linked mutations. These results demonstrate that ALS-linked mutations can variably cause loss of nuclear functions of TLS depending on the degree of impairment in nuclear localization.
Laboratory for Structural Neuropathology, Brain Science Institute, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama, 351-0198, Japan.
Yoshihiro
Y
Kino
Chika
C
Washizu
Elisa
E
Aquilanti
Misako
M
Okuno
Masaru
M
Kurosawa
Mizuki
M
Yamada
Hiroshi
H
Doi
Nobuyuki
N
Nukina
D017500:Adenovirus E1A Proteins / Q000235:genetics / Q000378:metabolism; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics*; D000818:Animals; D002460:Cell Line; D003594:Cytoplasmic Granules / Q000737:chemistry; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D051379:Mice; D009154:Mutation; D012326:RNA Splicing; D034702:RNA-Binding Protein FUS / Q000032:analysis / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000032:analysis
D017500:Adenovirus E1A Proteins; D034702:RNA-Binding Protein FUS; D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins