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Defective structural RNA processing in relapsing-remitting multiple sclerosis.

Spurlock CF, Tossberg JT, Guo Y, Sriram S, Crooke PS, Aune TM - Genome Biol. (2015)

Bottom Line: We report profound defects in surveillance of structural RNAs in RRMS exemplified by elevated levels of poly(A) + Y1-RNA, poly(A) + 18S rRNA and 28S rRNAs, elevated levels of misprocessed 18S and 28S rRNAs and levels of the U-class of small nuclear RNAs.In cell lines, silencing of the genes encoding Ro60 and La proteins gives rise to these same defects in surveillance of structural RNAs.Our results establish that profound defects in structural RNA surveillance exist in RRMS and establish a causal link between Ro60 and La proteins and integrity of structural RNAs.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA. chase.spurlock@vanderbilt.edu.

ABSTRACT

Background: Surveillance of integrity of the basic elements of the cell including DNA, RNA, and proteins is a critical element of cellular physiology. Mechanisms of surveillance of DNA and protein integrity are well understood. Surveillance of structural RNAs making up the vast majority of RNA in a cell is less well understood. Here, we sought to explore integrity of processing of structural RNAs in relapsing remitting multiple sclerosis (RRMS) and other inflammatory diseases.

Results: We employed mononuclear cells obtained from subjects with RRMS and cell lines. We used quantitative-PCR and whole genome RNA sequencing to define defects in structural RNA surveillance and siRNAs to deplete target proteins. We report profound defects in surveillance of structural RNAs in RRMS exemplified by elevated levels of poly(A) + Y1-RNA, poly(A) + 18S rRNA and 28S rRNAs, elevated levels of misprocessed 18S and 28S rRNAs and levels of the U-class of small nuclear RNAs. Multiple sclerosis is also associated with genome-wide defects in mRNA splicing. Ro60 and La proteins, which exist in ribonucleoprotein particles and play different roles in quality control of structural RNAs, are also deficient in RRMS. In cell lines, silencing of the genes encoding Ro60 and La proteins gives rise to these same defects in surveillance of structural RNAs.

Conclusions: Our results establish that profound defects in structural RNA surveillance exist in RRMS and establish a causal link between Ro60 and La proteins and integrity of structural RNAs.

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Related in: MedlinePlus

Interferon-β1b (IFN-β1b) therapy corrects aberrant levels of TROVE2, SSB, poly (A) + Y1 RNA, and poly(A) + U1 snRNA in RRMS. Blood samples were collected in PaxGene tubes from CTRL (N = 12), RRMS subjects not on IFN-β1b (RRMS - IFN-β1b, N = 12), and RRMS subjects on stable IFN-β1b therapy (RRMS + IFN-β1b, N = 4). Oligo dT was used for cDNA synthesis. Transcript levels of TROVE2 and SSB (A) or poly(A) + Y1 RNA and poly(A) + U1 RNA (B) were determined by quantitative PCR and normalized to CTRL = 1 after normalization to levels of GAPDH. Error bars are ± S.D. *P <0.05.
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Fig6: Interferon-β1b (IFN-β1b) therapy corrects aberrant levels of TROVE2, SSB, poly (A) + Y1 RNA, and poly(A) + U1 snRNA in RRMS. Blood samples were collected in PaxGene tubes from CTRL (N = 12), RRMS subjects not on IFN-β1b (RRMS - IFN-β1b, N = 12), and RRMS subjects on stable IFN-β1b therapy (RRMS + IFN-β1b, N = 4). Oligo dT was used for cDNA synthesis. Transcript levels of TROVE2 and SSB (A) or poly(A) + Y1 RNA and poly(A) + U1 RNA (B) were determined by quantitative PCR and normalized to CTRL = 1 after normalization to levels of GAPDH. Error bars are ± S.D. *P <0.05.

Mentions: For all analyses above, RRMS subjects were either on copaxone or no immunomodulatory therapy. Thus, we compared these subjects to RRMS on stable betaseron therapy. We found that levels of TROVE2, SSB, poly(A) + Y1 RNA and poly(A) + U1 snRNA were close to CTRL levels in RRMS subjects on betaseron therapy compared to RRMS subjects on either copaxone or no immunomodulatory therapy (Figure 6A, B). We examined responses of three individuals in longitudinal studies who initiated betaseron and found that correction of levels of TROVE2, SSB, poly(A) + Y1 RNA and poly(A) + U1 RNA was very rapid. We hypothesize that signaling pathways either directly or indirectly activated by betaseron interfere with signaling pathways driving defects in polyadenylation of structural RNAs in and expression of TROVE2 and SSB in RRMS and that betaseron will be a useful tool to identify underlying mechanisms. Further, measurement of polyadenylated species of ncRNAs may provide a useful means to monitor responses to betaseron or other immunomodulatory therapies in RRMS.Figure 6


Defective structural RNA processing in relapsing-remitting multiple sclerosis.

Spurlock CF, Tossberg JT, Guo Y, Sriram S, Crooke PS, Aune TM - Genome Biol. (2015)

Interferon-β1b (IFN-β1b) therapy corrects aberrant levels of TROVE2, SSB, poly (A) + Y1 RNA, and poly(A) + U1 snRNA in RRMS. Blood samples were collected in PaxGene tubes from CTRL (N = 12), RRMS subjects not on IFN-β1b (RRMS - IFN-β1b, N = 12), and RRMS subjects on stable IFN-β1b therapy (RRMS + IFN-β1b, N = 4). Oligo dT was used for cDNA synthesis. Transcript levels of TROVE2 and SSB (A) or poly(A) + Y1 RNA and poly(A) + U1 RNA (B) were determined by quantitative PCR and normalized to CTRL = 1 after normalization to levels of GAPDH. Error bars are ± S.D. *P <0.05.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4403723&req=5

Fig6: Interferon-β1b (IFN-β1b) therapy corrects aberrant levels of TROVE2, SSB, poly (A) + Y1 RNA, and poly(A) + U1 snRNA in RRMS. Blood samples were collected in PaxGene tubes from CTRL (N = 12), RRMS subjects not on IFN-β1b (RRMS - IFN-β1b, N = 12), and RRMS subjects on stable IFN-β1b therapy (RRMS + IFN-β1b, N = 4). Oligo dT was used for cDNA synthesis. Transcript levels of TROVE2 and SSB (A) or poly(A) + Y1 RNA and poly(A) + U1 RNA (B) were determined by quantitative PCR and normalized to CTRL = 1 after normalization to levels of GAPDH. Error bars are ± S.D. *P <0.05.
Mentions: For all analyses above, RRMS subjects were either on copaxone or no immunomodulatory therapy. Thus, we compared these subjects to RRMS on stable betaseron therapy. We found that levels of TROVE2, SSB, poly(A) + Y1 RNA and poly(A) + U1 snRNA were close to CTRL levels in RRMS subjects on betaseron therapy compared to RRMS subjects on either copaxone or no immunomodulatory therapy (Figure 6A, B). We examined responses of three individuals in longitudinal studies who initiated betaseron and found that correction of levels of TROVE2, SSB, poly(A) + Y1 RNA and poly(A) + U1 RNA was very rapid. We hypothesize that signaling pathways either directly or indirectly activated by betaseron interfere with signaling pathways driving defects in polyadenylation of structural RNAs in and expression of TROVE2 and SSB in RRMS and that betaseron will be a useful tool to identify underlying mechanisms. Further, measurement of polyadenylated species of ncRNAs may provide a useful means to monitor responses to betaseron or other immunomodulatory therapies in RRMS.Figure 6

Bottom Line: We report profound defects in surveillance of structural RNAs in RRMS exemplified by elevated levels of poly(A) + Y1-RNA, poly(A) + 18S rRNA and 28S rRNAs, elevated levels of misprocessed 18S and 28S rRNAs and levels of the U-class of small nuclear RNAs.In cell lines, silencing of the genes encoding Ro60 and La proteins gives rise to these same defects in surveillance of structural RNAs.Our results establish that profound defects in structural RNA surveillance exist in RRMS and establish a causal link between Ro60 and La proteins and integrity of structural RNAs.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA. chase.spurlock@vanderbilt.edu.

ABSTRACT

Background: Surveillance of integrity of the basic elements of the cell including DNA, RNA, and proteins is a critical element of cellular physiology. Mechanisms of surveillance of DNA and protein integrity are well understood. Surveillance of structural RNAs making up the vast majority of RNA in a cell is less well understood. Here, we sought to explore integrity of processing of structural RNAs in relapsing remitting multiple sclerosis (RRMS) and other inflammatory diseases.

Results: We employed mononuclear cells obtained from subjects with RRMS and cell lines. We used quantitative-PCR and whole genome RNA sequencing to define defects in structural RNA surveillance and siRNAs to deplete target proteins. We report profound defects in surveillance of structural RNAs in RRMS exemplified by elevated levels of poly(A) + Y1-RNA, poly(A) + 18S rRNA and 28S rRNAs, elevated levels of misprocessed 18S and 28S rRNAs and levels of the U-class of small nuclear RNAs. Multiple sclerosis is also associated with genome-wide defects in mRNA splicing. Ro60 and La proteins, which exist in ribonucleoprotein particles and play different roles in quality control of structural RNAs, are also deficient in RRMS. In cell lines, silencing of the genes encoding Ro60 and La proteins gives rise to these same defects in surveillance of structural RNAs.

Conclusions: Our results establish that profound defects in structural RNA surveillance exist in RRMS and establish a causal link between Ro60 and La proteins and integrity of structural RNAs.

Show MeSH
Related in: MedlinePlus