TP73-AS1在肿瘤中的表达及调控作用

<正>随着高通量测序技术的发展,成千上万种长链非编码RNA(long non-coding RNA,lncRNA)进入人们的视野。lncRNA是一类长度超过200个核苷酸并缺少开放阅读框的不具备蛋白质编码功能的RNA~([1-2])。研究发现lncRNA参与诸多生物学进程的关键步骤,包括染色质重塑、基因转录、转录后调节和蛋白质翻译等~([3-5])。LncRNA机制的不断被阐明,也为肿瘤的研究提供了新的可能。LncRNA在多种肿瘤的增殖、迁移侵袭和抗凋亡     

Three mitochondrial unassigned open reading frames of Podospora anserina represent remnants of a viral-type RNA polymerase gene

The mitochondrial DNA of Podospora anserina is complex, consisting of a characteristic set of genes with a large number of introns and a substantial amount of sequence of unknown function and origin. In addition, as indicated by various types of reorganization, this genome is highly flexible. Here we report the identification of three unassigned mitochondrial open reading frames (ORF P', ORF Q', ORF 11) as remnants of a rearranged viral-type RNA polymerase gene. These ORFs are not transcribed and may be derived from the integration of a linear plasmid of the type recently identified in a mutant of P. anserina.     

Intraaxonaler transport von Ethidium-Bromid-sensitiven RNS- und niedermolekularen 3H-Uridin-Verbindungen im tractus opticus von teleosteern

Zusammenfassung Am Sehtrakt von Carassius carassius und Scardinius erythrophthalmus wurde die axonale Ausbreitungsweise hoch- und niedermolekularer 3H-Uridin-Verbindungen untersucht. Dabei wurde nach intraocularer Injektion des Tracers für TCE-resistente Verbindungen eine intraaxonale Transportgeschwindigkeit von 2–4 mm/d bestimmt, für TCE-lösliche Verbindungen eine von ca. 30–50 mm/d. Durch Applikation des spezifisch mitochondrialen RNS-Synthese-Hemmers Ethidium-Bromid konnte die Einbaurate von 3H-Uridin in hochmolekulare RNS um 70–80% erniedrigt werden, was dafür spricht, daß die langsam im Axoplasma wandernden Mitochondrien einen Großteil der axonalen RNS synthetisieren.In der TCE-löslichen Fraktion konnten durch dünnschichtchromatographische Analyse noch nach 8d p. i. 3H-Uridin und 3H-UDPG nachgewiesen werden. Dieser Befund wird hinsichtlich eines transneuronalen Stoffübertritts von Uridin und der möglichen Bedeutung des UDPG-Transportes im Nervengewebe diskutiert.

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Intraaxonal transport of ethidium-bromide-sensitive RNA- and lowmolecular 3H-uridine-compounds in the optic tract of teleost

Summary In the optic system of teleosts (Carassius carassius and Scardinius erythrophthalmus) the axonal flow of high and low molecular 3H-uridine-compounds was investigated. After injection of the tracer into one eyeball and TCA-extraction of the samples a transport-rate of 2–4 mm/d was demonstrated. By the specific inhibitor of mitochondrial RNA-synthesis, Ethidium-Bromide, the amount of axonal radioactivity could be reduced to 20–30% of the control. This indicates the mitochondria as being the site of synthesis most of axonal RNA. Considering the TCA-soluble 3H-uridine-compounds, an intraaxonal flow also could be demonstrated, with a transport-rate of 30–50 mm/d, 16 times higher as the one of RNA. The analysis by thin layer chromatography indicated the existence of 3H-uridine and 3H-UDPG in the axonal fraction of TCA-soluble compounds still after an incorporation time of 8d. The possibility of a transneuronal convection of uridine and the function of UDPG-transport in the axon are discussed.

Frau Prof. Dr. H. Kersten (Erlangen) danke ich für die Überlassung einer Probe Ethidium-Bromid.     

Synthesis and function of the mitochondrial intron —encoded bI4 RNA maturase from Saccharomyces cerevisiae

Summary We have analyzed the expression and function of the intron-encoded bI4 maturase when frame-shift mutations in the upstream exon alter the translational process. By constructing secondary cis-acting mutations within the b14 intron, we observed (1) that the bI4 maturase is still translated in the presence of the upstream mutation, albeit in very low amounts, and (2) that the limited amounts of bI4 maturase made under these conditions is no longer able to promote the splicing process of the aI4 intron. These observations, which further strengthen the maturase model, strongly suggest that bI4 maturase acts sequentially on the bI4 intron and then on the aI4 intron.     

Setting out the frame conditions for feasible use of FFPE derived RNA

Introduction

The usage of formalin-fixed paraffin embedded (FFPE) tissue is characterized by its long shelf-life and simple handling. Therefore it is the most commonly available tissue specimen in routine diagnostics and histological studies. Formaldehyde fixation may result in RNA degradation and cross linking with proteins, while storage conditions also affect RNA integrity. The present study was designed to investigate the influence of these factors on RNA analysis.

人细胞色素P450 前mRNA的可变剪接研究进展

Human genes typically contain multiple introns, and in many cases the exons can be joined more than one way to generate multiple rnRNAs, encoding distinct protein isoforms. This process is called alternative splicing. The article summarized the human cytochrome P450 pre-mRNA alternative splicing and their regulatory mechanism and impacts on biological functions.