title: Comprehensive discovery and characterization of small RNAs in Corynebacterium glutamicum ATCC 13032.
abstract: BACKGROUND
  Recent discoveries on bacterial transcriptomes gave evidence that small RNAs (sRNAs) have important regulatory roles in prokaryotic cells. Modern high-throughput sequencing approaches (RNA-Seq) enable the most detailed view on transcriptomes offering an unmatched comprehensiveness and single-base resolution. Whole transcriptome data obtained by RNA-Seq can be used to detect and characterize all transcript species, including small RNAs. Here, we describe an RNA-Seq approach for comprehensive detection and characterization of small RNAs from Corynebacterium glutamicum, an actinobacterium of high industrial relevance and model organism for medically important Corynebacterianeae, such as C. diphtheriae and Mycobacterium tuberculosis.
  
  
  RESULTS
  In our RNA-Seq approach, total RNA from C. glutamicum ATCC 13032 was prepared from cultures grown in minimal medium at exponential growth or challenged by physical (heat shock, cold shock) or by chemical stresses (diamide, H2O2, NaCl) at this time point. Total RNA samples were pooled and sequencing libraries were prepared from the isolated small RNA fraction. High throughput short read sequencing and mapping yielded over 800 sRNA genes. By determining their 5'- and 3'-ends and inspection of their locations, these potential sRNA genes were classified into UTRs of mRNAs (316), cis-antisense sRNAs (543), and trans-encoded sRNAs (262). For 77 of trans-encoded sRNAs significant sequence and secondary structure conservation was found by a computational approach using a whole genome alignment with the closely related species C. efficiens YS-314 and C. diphtheriae NCTC 13129. Three selected trans-encoded sRNAs were characterized by Northern blot analysis and stress-specific transcript patterns were found.
  
  
  CONCLUSIONS
  The study showed comparable numbers of sRNAs known from genome-wide surveys in other bacteria. In detail, our results give deep insight into the comprehensive equipment of sRNAs in C. glutamicum and provide a sound basis for further studies concerning the functions of these sRNAs.
authors.forename: Almut
authors.initials: A
authors.lastname: Mentz
authors.forename: Armin
authors.initials: A
authors.lastname: Neshat
authors.forename: Katharina
authors.initials: K
authors.lastname: Pfeifer-Sancar
authors.forename: Alfred
authors.initials: A
authors.lastname: Pühler
authors.forename: Christian
authors.initials: C
authors.lastname: Rückert
authors.affiliation: Microbial Genomics and Biotechnology, Center for Biotechnology, Bielefeld University, Universitätsstraße 27, 33615, Bielefeld, Germany. joern.kalinowski@cebitec.uni-bielefeld.de.
authors.forename: Jörn
authors.initials: J
authors.lastname: Kalinowski
mesh_terms: D048230:Corynebacterium glutamicum / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D003958:Diamide / Q000633:toxicity; D015723:Gene Library; D059014:High-Throughput Nucleotide Sequencing; D006861:Hydrogen Peroxide / Q000633:toxicity; D009690:Nucleic Acid Conformation; D016372:RNA, Antisense / Q000737:chemistry / Q000378:metabolism; D012329:RNA, Bacterial / Q000302:isolation & purification / Q000378:metabolism*; D012333:RNA, Messenger / Q000737:chemistry / Q000378:metabolism; D058727:RNA, Small Untranslated / Q000737:chemistry / Q000378:metabolism; D017423:Sequence Analysis, RNA; D012965:Sodium Chloride / Q000494:pharmacology; D013696:Temperature
chemical_list: D016372:RNA, Antisense; D012329:RNA, Bacterial; D012333:RNA, Messenger; D058727:RNA, Small Untranslated; D003958:Diamide; D012965:Sodium Chloride; D006861:Hydrogen Peroxide