Search

Nine polyglutamine (polyQ) proteins have already been identified that are considered to be associated with the pathologies of neurodegenerative disorders called polyQ diseases, but whether these polyQ proteins mutually interact and synergize in proteinopathies remains to be elucidated. In this study, 4 polyQ-containing proteins, androgen receptor (AR), ataxin-7 (Atx7), huntingtin (Htt) and ataxin-3 (Atx3), are used as model molecules to investigate their heterologous coaggregation and consequent impact on cellular proteostasis. Our data indicate that the N-terminal fragment of polyQ-expanded (PQE) Atx7 or Htt can coaggregate with and sequester AR and Atx3 into insoluble aggregates or inclusions through their respective polyQ tracts. In vitro coprecipitation and NMR titration experiments suggest that this specific coaggregation depends on polyQ lengths and is probably mediated by polyQ-tract interactions. Luciferase reporter assay shows that these coaggregation and sequestration effects can deplete the cellular availability of AR and consequently impair its transactivation function. This study provides valid evidence supporting the viewpoint that coaggregation of polyQ proteins is mediated by polyQ-tract interactions and benefits our understanding of the molecular mechanism underlying the accumulation of different polyQ proteins in inclusions and their copathological causes of polyQ diseases.

The purpose of this study is trying to analysis the homology between four lentogenic Class I genotype 3 Newcastle disease virus isolates from different hosts with NDV strain NDV 08-004, which was the first obtained complete genome sequence virus of class I genotype 3. The full-length genome of NDV isolates, JS/3/09/Ch, ZJ/3/10/Ch, AH/2/10/Du and JS/9/08/Go,were determined by RT-PCR and then an alyzed. All the genomes are 15 198 nucleotides (nt) in length. Compared with the full genome sequences of Class II NDV stains (genotype IV-IX),four isolates has a 6-nt deletion in the non-coding region of nuclear phosphoprotein gene between nucleotides 1 640-1 641 and 12-nt insertion in the coding region of phospho protein gene between nucleotides 2 381-2 382. All the isolates have the motifs 112EQ/RQE/GRL117 at the cleavage site of the fusion protein, which is typical of lenogenic NDV strains, and it is in agreement with the result of pathogenic tests. The full-length genome of 4 genotype 3 NDV isolates shared 93% nucleotide identity with NDV08-004. The results of alignment of 6 viral genes showed that NP gene shared the highest identity (98.3%-96.4%) and P gene shared the lowest identity (96.1%-91.9%). The results show the following two points. First, it is concluded that the isolates from different hosts share the same genotype has the insignificant divergence in the genetic information. Second, it is proposed that the mutation rates of NP/F/L genes are lower than P/M/HN genes.