bioRxiv preprint doi: https://doi.org/10.1101/356071; this version posted June 28, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Distinct isoforms of Nrf1 diversely regulate different subsets of its cognate target genes Meng Wang, Lu Qiu, Xufang Ru, Yijiang Song, Yiguo Zhang* The Laboratory of Cell Biochemistry and Topogenetic Regulation, College of Bioengineering and Faculty of Sciences, Chongqing University, No. 174 Shazheng Street, Shapingba District, Chongqing 400044, China *Correspondence should be addressed to Yiguo Zhang (email:
[email protected] or
[email protected]). Abstract The single Nrf1 gene has capability to be differentially transcripted alongside with alternative mRNA-splicing and subsequent translation through different initiation signals so as to yield distinct lengths of polypeptide isoforms. Amongst them, three of the most representatives are Nrf1α, Nrf1β and Nrf1γ, but the putative specific contribution of each isoform to regulating ARE-driven target genes remains unknown. To address this, we have here established three cell lines on the base of the Flp-In™ T-REx™ system, which are allowed for tetracycline-inducibly stable expression of Nrf1α, Nrf1β and Nrf1γ. The RNA-Sequencing results have demonstrated that a vast majority of differentially expressed genes (i.e. 90 DEGs detected) were dominantly up-regulated by Nrf1α and/or Nrf1β following induction by tetracycline. By contrast, other DEGs regulated by Nrf1γ were far less than those regulated by Nrf1α/β (i.e. ~11 of Nrf1α and 7 of Nrf1β). Further transcriptomic analysis revealed that tetracycline-induced expression of Nrf1γ significantly increased the percentage of down-regulated genes in total DEGs.