02503nas a2200325 4500008004100000022001400041245012000055210006900175260001300244300001100257490000600268520148900274653002501763653001601788653002501804653002101829653003801850653001201888653003301900100002501933700002101958700002801979700002002007700001902027700002502046700001802071700001802089700002102107856004902128 2015 eng d a1752-986700aEnvironmental stresses modulate abundance and timing of alternatively spliced circadian transcripts in Arabidopsis.0 aEnvironmental stresses modulate abundance and timing of alternat c2015 Feb a207-270 v83 a

Environmental stresses profoundly altered accumulation of nonsense mRNAs including intron-retaining (IR) transcripts in Arabidopsis. Temporal patterns of stress-induced IR mRNAs were dissected using both oscillating and non-oscillating transcripts. Broad-range thermal cycles triggered a sharp increase in the long IR CCA1 isoforms and altered their phasing to different times of day. Both abiotic and biotic stresses such as drought or Pseudomonas syringae infection induced a similar increase. Thermal stress induced a time delay in accumulation of CCA1 I4Rb transcripts, whereas functional mRNA showed steady oscillations. Our data favor a hypothesis that stress-induced instabilities of the central oscillator can be in part compensated through fluctuations in abundance and out-of-phase oscillations of CCA1 IR transcripts. Taken together, our results support a concept that mRNA abundance can be modulated through altering ratios between functional and nonsense/IR transcripts. SR45 protein specifically bound to the retained CCA1 intron in vitro, suggesting that this splicing factor could be involved in regulation of intron retention. Transcriptomes of nonsense-mediated mRNA decay (NMD)-impaired and heat-stressed plants shared a set of retained introns associated with stress- and defense-inducible transcripts. Constitutive activation of certain stress response networks in an NMD mutant could be linked to disequilibrium between functional and nonsense mRNAs.

10aAlternative Splicing10aArabidopsis10aArabidopsis Proteins10aCircadian Clocks10aGene Expression Regulation, Plant10aIntrons10aNonsense Mediated mRNA Decay1 aFilichkin, Sergei, A1 aCumbie, Jason, S1 aDharmawardhana, Palitha1 aJaiswal, Pankaj1 aChang, Jeff, H1 aPalusa, Saiprasad, G1 aReddy, A, S N1 aMegraw, Molly1 aMockler, Todd, C uhttps://megraw.cgrb.oregonstate.edu/node/31502178nas a2200277 4500008004100000022001400041245011900055210006900174260000900243300000800252490000700260520133000267653001601597653001701613653001801630653001901648653001601667653003001683653002701713653001301740653003401753100002101787700002501808700001801833856004901851 2015 eng d a1471-216400aNanoCAGE-XL and CapFilter: an approach to genome wide identification of high confidence transcription start sites.0 aNanoCAGEXL and CapFilter an approach to genome wide identificati c2015 a5970 v163 a

BACKGROUND: Identifying the transcription start sites (TSS) of genes is essential for characterizing promoter regions. Several protocols have been developed to capture the 5' end of transcripts via Cap Analysis of Gene Expression (CAGE) or linker-ligation strategies such as Paired-End Analysis of Transcription Start Sites (PEAT), but often require large amounts of tissue. More recently, nanoCAGE was developed for sequencing on the Illumina GAIIx to overcome these difficulties.

RESULTS: Here we present the first publicly available adaptation of nanoCAGE for sequencing on recent ultra-high throughput platforms such as Illumina HiSeq-2000, and CapFilter, a computational pipeline that greatly increases confidence in TSS identification. We report excellent gene coverage, reproducibility, and precision in transcription start site discovery for samples from Arabidopsis thaliana roots.

CONCLUSION: nanoCAGE-XL together with CapFilter allows for genome wide identification of high confidence transcription start sites in large eukaryotic genomes.

[Link to Protocol, Additional Data, and Supplementary Materials]

[Link to CapFilter Software]

10aArabidopsis10aGenes, Plant10aGenome, Plant10aNanotechnology10aPlant Roots10aPromoter Regions, Genetic10aSequence Analysis, DNA10aSoftware10aTranscription Initiation Site1 aCumbie, Jason, S1 aIvanchenko, Maria, G1 aMegraw, Molly uhttps://megraw.cgrb.oregonstate.edu/node/311