title: Mechanism for stabilizing mRNAs involved in methanol-dependent methanogenesis of cold-adaptive Methanosarcina mazei zm-15.
abstract: Methylotrophic methanogenesis predominates at low temperatures in the cold Zoige wetland in Tibet. To elucidate the basis of cold-adapted methanogenesis in these habitats, Methanosarcina mazei zm-15 was isolated, and the molecular basis of its cold activity was studied. For this strain, aceticlastic methanogenesis was reduced 7.7-fold during growth at 15°C versus 30°C. Methanol-derived methanogenesis decreased only 3-fold under the same conditions, suggesting that it is more cold adaptive. Reverse transcription-quantitative PCR (RT-qPCR) detected <2-fold difference in the transcript abundances of mtaA1, mtaB1, and mtaC1, the methanol methyltransferase (Mta) genes, in 30°C versus 15°C culture, while ackA and pta mRNAs, encoding acetate kinase (Ack) and phosphotransacetylase (Pta) in aceticlastic methanogenesis, were 4.5- and 6.8-fold higher in 30°C culture than in 15°C culture. The in vivo half-lives of mtaA1 and mtaC1B1 mRNAs were similar in 30°C and 15°C cultures. However, the pta-ackA mRNA half-life was significantly reduced in 15°C culture compared to 30°C culture. Using circularized RNA RT-PCR, large 5' untranslated regions (UTRs) (270 nucleotides [nt] and 238 nt) were identified for mtaA1 and mtaC1B1 mRNAs, while only a 27-nt 5' UTR was present in the pta-ackA transcript. Removal of the 5' UTRs significantly reduced the in vitro half-lives of mtaA1 and mtaC1B1 mRNAs. Remarkably, fusion of the mtaA1 or mtaC1B1 5' UTRs to pta-ackA mRNA increased its in vitro half-life at both 30°C and 15°C. These results demonstrate that the large 5' UTRs significantly enhance the stability of the mRNAs involved in methanol-derived methanogenesis in the cold-adaptive M. mazei zm-15.
authors: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China.
authors: Yi
authors: Y
authors: Cao
authors: Jie
authors: J
authors: Li
authors: Na
authors: N
authors: Jiang
authors: Xiuzhu
authors: X
authors: Dong
mesh_terms: D020121:5' Untranslated Regions; D003080:Cold Temperature; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D020869:Gene Expression Profiling; D008697:Methane / Q000378:metabolism*; D000432:Methanol / Q000378:metabolism*; D017020:Methanosarcina / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism* / Q000528:radiation effects; D008969:Molecular Sequence Data; D020871:RNA Stability; D012333:RNA, Messenger / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D018609:Tibet
chemical_list: D020121:5' Untranslated Regions; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012333:RNA, Messenger; D012336:RNA, Ribosomal, 16S; D008697:Methane; D000432:Methanol