Document Type

Article

Publication Date

6-29-2017

Comments

This article has been peer reviewed. It was published in: PLoS ONE.

Volume 12, Issue 6, June 2017, Article number e0180657.

The published version is available at DOI: 10.1371/journal.pone.0180657

Copyright © 2017 Gentillon et al

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

C5-substituted 2,4-diaminoquinazolines (2,4-DAQs) ameliorate disease severity in SMA mice. It is uncertain, however, that these compounds increase SMN protein levels in vivo even though they were identified as activators of the SMN2 promoter. These compounds also regulate the expression of other transcripts in neuroblastoma cells. In this study, we investigate the mechanism by which the 2,4-DAQs regulate the expression of SMN2 as well as other targets. D156844, D158872, D157161 and D157495 (RG3039) increased SMN2 promoter-driven reporter gene activity by at least 3-fold in NSC-34 cells. These compounds, however, did not significantly increase SMN2 mRNA levels in type II SMA fibroblasts nor in NSC-34 cells, although there was a trend for these compounds increasing SMN protein in SMA fibroblasts. The number of SMN-containing gems was increased in SMA fibroblasts in response to 2,4-DAQ treatment in a dose-dependent manner. ATOH7 mRNA levels were significantly lower in type II SMA fibroblasts. 2,4-DAQs significantly increased ATOH7, DRNT1 and DRTN2 transcript levels in type II SMA fibroblasts and restored ATOH7 levels to those observed in healthy fibroblasts. These compounds also increase Atoh7 mRNA expression in NSC-34 cells. In conclusion, 2,4-DAQs regulate SMN2 by increasing protein levels and gem localization. They also increase ATOH7, DRNT1 and DRNT2 transcript levels. This study reveals that the protective effects of 2,4-DAQs in SMA may be independent of SMN2 gene regulation. These compounds could be used in concert with a proven SMN2 inducer to develop a multi-faceted approach to treating SMA.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.

Included in

Pediatrics Commons

Share

COinS