title: Analysis of the transcriptional regulator GlpR, promoter elements, and posttranscriptional processing involved in fructose-induced activation of the phosphoenolpyruvate-dependent sugar phosphotransferase system in Haloferax mediterranei.
abstract: Among all known archaeal strains, the phosphoenolpyruvate-dependent phosphotransferase system (PTS) for fructose utilization is used primarily by haloarchaea, which thrive in hypersaline environments, whereas the molecular details of the regulation of the archaeal PTS under fructose induction remain unclear. In this study, we present a comprehensive examination of the regulatory mechanism of the fructose PTS in the haloarchaeon Haloferax mediterranei. With gene knockout and complementation, microarray analysis, and chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR), we revealed that GlpR is the indispensable activator, which specifically binds to the PTS promoter (PPTS) during fructose induction. Further promoter-scanning mutation indicated that three sites located upstream of the H. mediterranei PPTS, which are conserved in most haloarchaeal PPTSs, are involved in this induction. Interestingly, two PTS transcripts (named T8 and T17) with different lengths of 5' untranslated region (UTR) were observed, and promoter or 5' UTR swap experiments indicated that the shorter 5' UTR was most likely generated from the longer one. Notably, the translation efficiency of the transcript with this shorter 5' UTR was significantly higher and the ratio of T8 (with the shorter 5' UTR) to T17 increased during fructose induction, implying that a posttranscriptional mechanism is also involved in PTS activation. With these insights into the molecular regulation of the haloarchaeal PTS, we have proposed a working model for haloarchaea in response to environmental fructose.
authors: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors: Lei
authors: L
authors: Cai
authors: Shuangfeng
authors: S
authors: Cai
authors: Dahe
authors: D
authors: Zhao
authors: Jinhua
authors: J
authors: Wu
authors: Lei
authors: L
authors: Wang
authors: Xiaoqing
authors: X
authors: Liu
authors: Ming
authors: M
authors: Li
authors: Jing
authors: J
authors: Hou
authors: Jian
authors: J
authors: Zhou
authors: Jingfang
authors: J
authors: Liu
authors: Jing
authors: J
authors: Han
authors: Hua
authors: H
authors: Xiang
mesh_terms: D047369:Chromatin Immunoprecipitation; D004252:DNA Mutational Analysis; D005632:Fructose / Q000378:metabolism*; D020869:Gene Expression Profiling; D055786:Gene Knockout Techniques; D005816:Genetic Complementation Test; D019623:Haloferax mediterranei / Q000235:genetics* / Q000378:metabolism; D046228:Microarray Analysis; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012326:RNA Splicing; D060888:Real-Time Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D014157:Transcription Factors; D005632:Fructose; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System