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The removal of introns by the spliceosome is a key gene regulatory mechanism in eukaryotes, with the U1 snRNP subunit playing a crucial role in the early stages of splicing. Studies in metazoans show that the U1 snRNP also conducts splicing-independent functions, but the lack of genetic tools and knowledge about U1 snRNP-associated proteins have limited the study of such splicing-independent functions in plants. Here we describe an RNA-centric approach that identified more than 200 proteins associated with the ArabidopsisU1 snRNP and revealed a tight link to mRNA cleavage and polyadenylation factors. Interestingly, we found that the U1 snRNP protects mRNAs against premature cleavage and polyadenylation within introns—a mechanism known as telescripting in metazoans—while also influencing alternative polyadenylation site selection in 3′-UTRs. Overall, our work provides a comprehensive view of U1 snRNP interactors and reveals novel functions in regulating mRNA 3′-end processing in Arabidopsis, laying the groundwork for understanding non-canonical functions of plant U1 snRNPs.

TFF3 is a secretory peptide belonging to the trefoil factor family with a predicted size of 59 amino acid residues containing seven cysteine residues. It is predominantly expressed in intestinal goblet cells where it plays a key role in mucosal regeneration and repair processes. In the course of these studies, human colonic TFF3 was shown to exist mainly as a high molecular weight heteromer. Purification of this heteromer and characterization by LC−ESI−MS/MS analysis identified the IgG Fc binding protein (FCGBP) as the disulfide-linked partner protein of TFF3. FCGBP is a constituent of intestinal mucus secreted by goblet cells. Furthermore, low amounts of TFF3/monomer and only little TFF3/dimer were detected in human colonic extracts. Here, we show that these TFF3 forms can be released from the purified TFF3-FCGBP heteromer complex in vitroby reduction with hydrogen sulfide (H2S). Such a mechanism would be in line with the high H2S concentrations reported to occur in the lumen of the colon. Of special note, this points to intestinal mucus as a reservoir for a biologically active peptide. Also proteolytic processing of FCGBP was observed which is in line with multiple autocatalytic cleavages as proposed earlier by Johansson et al. (J. Proteome Res.2009, 8, 3549−3557).

Recent findings suggest that alternative splicing has a critical role in controlling the responses of plants to temperature variations. However, alternative splicing factors in plants are largely uncharacterized. Here we establish the putative splice regulator, PORCUPINE (PCP), as temperature-specific regulator of development in Arabidopsis thaliana. Our findings point to the misregulation of WUSCHELand CLAVATA3as the possible cause for the meristem defects affecting the pcp-1loss-of-function mutants at low temperatures. Plants are sensitive to temperature changes. Now, researchers have found an alternative splicing factor that is essential for the development of Arabidopsisunder low temperature, and bridges between alternative splicing and temperature sensitivity.

Background: Accurate and comprehensive annotation of transcript sequences is essential for transcript quantification and differential gene and transcript expression analysis. Single-molecule long-read sequencing technologies provide improved integrity of transcript structures including alternative splicing, and transcription start and polyadenylation sites. However, accuracy is significantly affected by sequencing errors, mRNA degradation, or incomplete cDNA synthesis. Results: We present a new and comprehensive Arabidopsis thalianaReference Transcript Dataset 3 (AtRTD3). AtRTD3 contains over 169,000 transcripts—twice that of the best current Arabidopsis transcriptome and including over 1500 novel genes. Seventy-eight percent of transcripts are from Iso-seq with accurately defined splice junctions and transcription start and end sites. We develop novel methods to determine splice junctions and transcription start and end sites accurately. Mismatch profiles around splice junctions provide a powerful feature to distinguish correct splice junctions and remove false splice junctions. Stratified approaches identify high-confidence transcription start and end sites and remove fragmentary transcripts due to degradation. AtRTD3 is a major improvement over existing transcriptomes as demonstrated by analysis of an Arabidopsis cold response RNA-seq time-series. AtRTD3 provides higher resolution of transcript expression profiling and identifies cold-induced differential transcription start and polyadenylation site usage. Conclusions: AtRTD3 is the most comprehensive Arabidopsis transcriptome currently. It improves the precision of differential gene and transcript expression, differential alternative splicing, and transcription start/end site usage analysis from RNA-seq data. The novel methods for identifying accurate splice junctions and transcription start/end sites are widely applicable and will improve single-molecule sequencing analysis from any species.

ABSTRACTNuclear migration depends on microtubules, the dynein motor complex, and regulatory components like LIS1 and NUDC. We sought to identify new binding partners of the fungal LIS1 homolog NUDF to clarify its function in dynein regulation. We therefore analyzed the association between NUDF and NUDC in Aspergillus nidulans. NUDF and NUDC directly interacted in yeast two-hybrid experiments via NUDF's WD40 domain. NUDC-green fluorescent protein (NUDC-GFP) was localized to immobile dots in the cytoplasm and at the hyphal cortex, some of which were spindle pole bodies (SPBs). We showed by bimolecular fluorescence complementation microscopy that NUDC directly interacted with NUDF at SPBs at different stages of the cell cycle. Applying tandem affinity purification, we isolated the NUDF-associated protein BNFA (for binding to NUDF). BNFA was dispensable for growth and for nuclear migration. GFP-BNFA fusions localized to SPBs at different stages of the cell cycle. This localization depended on NUDF, since the loss of NUDF resulted in the cytoplasmic accumulation of BNFA. BNFA did not bind to NUDC in a yeast two-hybrid assay. These results show that the conserved NUDF and NUDC proteins play a concerted role at SPBs at different stages of the cell cycle and that NUDF recruits additional proteins specifically to the dynein complex at SPBs.

Nuclear migration depends on microtubules, the dynein motor complex, and regulatory components like LIS1 and NUDC. We sought to identify new binding partners of the fungal LIS1 homolog NUDF to clarify its function in dynein regulation. We therefore analyzed the association between NUDF and NUDC in Aspergillus nidulans. NUDF and NUDC directly interacted in yeast two-hybrid experiments via NUDF's WD40 domain. NUDC-green fluorescent protein (NUDC-GFP) was localized to immobile dots in the cytoplasm and at the hyphal cortex, some of which were spindle pole bodies (SPBs). We showed by bimolecular fluorescence complementation microscopy that NUDC directly interacted with NUDF at SPBs at different stages of the cell cycle. Applying tandem affinity purification, we isolated the NUDF-associated protein BNFA (for binding to NUDF). BNFA was dispensable for growth and for nuclear migration. GFP-BNFA fusions localized to SPBs at different stages of the cell cycle. This localization depended on NUDF, since the loss of NUDF resulted in the cytoplasmic accumulation of BNFA. BNFA did not bind to NUDC in a yeast two-hybrid assay. These results show that the conserved NUDF and NUDC proteins play a concerted role at SPBs at different stages of the cell cycle and that NUDF recruits additional proteins specifically to the dynein complex at SPBs.

Zusammenfassung: Das Thoraxtrauma, zumeist im Rahmen eines Polytraumas, ist die hauptsächliche Todesursache bei Menschen unter 45 Jahren. Dabei stellen thorakale Traumen bei Mehrfachverletzen durch zumeist stumpfe Gewalteinwirkung über die letzten 3 Jahrzehnte hinweg mit ziemlich konstant 80% die häufigste relevante Verletzung dar. Isolierte Thoraxtraumen machen dagegen nur 25% aller Verletzungen aus. Mehr als 90% sind stumpfe Thoraxtraumen, 5–10% penetrierende Verletzungen. Die Überlebenschancen sind dabei z. T. unmittelbar bzw. mit einer etwa 25%igen Letalität maßgeblich durch das thorakale Trauma bestimmt. Das Verletzungsmuster beim Thoraxtrauma ist sehr vielgestaltig. Es betrifft den knöchernen Thorax mit Diaphragma, das Lungenparenchym, einschließlich der Atemwege, und das Mediastinum. Dabei sind vielfältige Kombinationen möglich. Anhand dieser Arbeit soll das diagnostisch und therapeutisch streng parallel ablaufende Vorgehen in der Primärphase der Behandlung vor Ort, in der Notaufnahme bis zur Erstversorgung dargestellt werden. Schwerpunkte sind die präklinischen Maßnahmen, das Schockraummanagement, einschließlich der apparativen Diagnostik durch Computertomographie, Sonographie und Endoskopie, sowie das prinzipielle klinisch-anästhesiologische Behandlungskonzept.

Das älteste heute bekannte Uranglas stammt aus dem Wandmosaik einer spätrömischen Villa nahe Neapel (79. n. Chr.). Für die moderne Chemie entdeckte Martin Heinrich Klaproth das Uran im Jahr 1789. Er erkannte schnell, dass Oxide und weitere Verbindungen des Urans sich gut zum Färben von Glasuren und Gläsern eignen. Ab Mitte des 19. Jahrhunderts entstanden sehr viele Objekte aus uranhaltigen Gläsern oder mit solchen Glasuren, etwa Geschirr, Ziergläser, Kacheln oder Bijouteriewaren. Manche dieser Objekte werden heute noch hergestellt, viele historische sind noch im Umlauf. Ihre Erforschung und strahlenhygienische Einordnung ist Aufgabe der konservatorischen Radiometrie.

Transcription of the gene encoding for the nuclear autoantigen La resulted in La mRNA isoforms. A promoter switching combined with an alternative splicing pathway replaced the exon 1 with the exon 1'. The exon 1' contained GC-rich regions and an oligo(U) tail of 23 uridine residues. Moreover, it encoded for three open reading frames upstream of the La protein reading frame. Despite this unusual structure, when exon 1' La mRNAs were expressed in transfected cells, both exon 1 and 1' La mRNAs were translated to La protein, whereas the upstream open reading frames of the exon 1' were not translated. In addition to full-length exon 1' La mRNAs 5'-shortened exon 1' La mRNAs were detected. The exon 1' 5'-starts varied in dependence on the analyzed tissues. Like the full-length exon 1' La mRNA a 5'-shortened exon 1' construct starting downstream of the oligo(U) tail but upstream of the open reading frames 2 and 3 was also well translated when transfected in mouse cells. Thus all La mRNA forms represent functional La mRNAs.

Zusammenfassung Das C-reaktive Protein ist ein pathologischer Eiweißkörper, der im Blute als Folge entzündlicher, nekrotischer und neoplastischer Reaktionen entsteht. Es wird beim akuten transmuralen Myokardinfarkt in 88–100% der Fälle (91% in unserer Serie) gefunden. Der Nachweis gelingt gewöhnlich am 2., spätestens aber am 3. Krankheitstag. Im Laufe der 3. Woche verschwindet es meistens wieder aus dem Blut. Der CRP-Test ist der BSG insofern überlegen, als CRP früher nachweisbar ist als ein Anstieg der BSG und sich mit Abklingen der entzündlichen Erscheinungen schneller wieder normalisiert. Beide Teste sind jedoch unspezifisch für den Myokardinfarkt. Vergleichende Beobachtungen von CRP, BSG, Leukocytenzahl und Serum-Glutamat-Oxalat-Transaminase (SGO-T) bei 59 Patienten mit akutem transmuralem und 43 Patienten mit nichttransmuralem Herzinfarkt werden vorgelegt.

The article offers tips that help minimize ones taxable income for 2010 in the U.S. It cites the Small Business Jobs Act of 2010, an act signed by President Barack Obama into law on September 27, 2010, which provisions offer small-business owners tax breaks and better access to credit. It mentions that there are several potential tax-planning opportunities of which one can take advantage as the year ends.

MicroRNAs (miRNAs) control many aspects of development and adaption in plants and in animals by post-transcriptional control of mRNA stability and translatability. Over the last years numerous proteins have been identified in the miRNA pathway. The versatile scaffold protein RACK1 has been associated with efficient miRNA production and function in plants and metazoans. Here, we briefly summarize the differences of RACK1 function in the plant and animal miRNA pathways and discuss putative mechanisms and functional roles of RACK1 in miRNA biogenesis and action.

The gene coding for the β-subunit of the sodium ion translocating ATP synthase from Propionigenium modestum was cloned and sequenced. The predicted amino acid sequence resembles that of the β-subunits from proton-translocating ATP synthases. The same conserved regions are found in both types of ATP synthases. This is a good indication that the β-subunits of the proton and sodium ion translocating ATP synthases have evolved from a common ancestor.