Search results for "D region"

Specific roles of 5′ RNA secondary structures in stabilizing transcripts in chloroplasts

2005

RNA secondary structures, e.g. stem-loops that are often found at the 5' and 3' ends of mRNAs, are in many cases known to be crucial for transcript stability but their role in prolonging the lifetime of transcripts remains elusive. In this study we show for an essential RNA-stabilizing stem-loop at the 5' end of rbcL gene transcripts in Chlamydomonas that it neither prevents ribonucleases from binding to the RNA nor impedes their movement along the RNA strand. The stem-loop has a formative function in that it mediates folding of a short sequence around its base into a specific RNA conformation, consisting of a helical and single-stranded region, i.e. the real structure required for longevit…

261 INFLUENCE OF IN VITRO MATURATION ON EPIGENETIC MARKS AND GENE EXPRESSION IN BOVINE OOCYTES

2011

In cattle, in vitro maturation (IVM) of oocytes is an integral part of assisted reproduction technology. However, only 30% of in vitro matured bovine oocytes develop to the blastocyst stage after fertilization (compared with 60% for in vivo matured oocytes), indicating critical involvement of maturation conditions in the developmental competence of oocytes. Oocytes for IVF and intracytoplasmic sperm injection in humans are typically allowed to mature in vivo after superovulation because IVM is not considered to be a safe medical procedure. Several studies have shown that assisted reproduction technology involving prolonged in vitro culture of human and ruminant embryos can be associated wi…

Structures of two molluscan hemocyanin genes: significance for gene evolution.

2001

We present here the description of genes coding for molluscan hemocyanins. Two distantly related mollusks, Haliotis tuberculata and Octopus dofleini , were studied. The typical architecture of a molluscan hemocyanin subunit, which is a string of seven or eight globular functional units (FUs, designated a to h, about 50 kDa each), is reflected by the gene organization: a series of eight structurally related coding regions in Haliotis , corresponding to FU-a to FU-h, with seven highly variable linker introns of 174 to 3,198 bp length (all in phase 1). In Octopus seven coding regions (FU-a to FU-g) are found, separated by phase 1 introns varying in length from 100 bp to 910 bp. Both genes exh…

2014

Genetic factors underlie a substantial proportion of individual differences in cognitive functions in humans, including processes related to episodic and working memory. While genetic association studies have proposed several candidate "memory genes", these currently explain only a minor fraction of the phenotypic variance. Here, we performed genome-wide screening on 13 episodic and working memory phenotypes in 1,318 participants of the Berlin Aging Study II aged 60 years or older. The analyses highlight a number of novel single nucleotide polymorphisms (SNPs) associated with memory performance, including one located in a putative regulatory region of microRNA (miRNA) hsa-mir-138-5p (rs9882…

Eukaryotic mRNA decay: methodologies, pathways, and links to other stages of gene expression.

2012

mRNA concentration depends on the balance between transcription and degradation rates. On both sides of the equilibrium, synthesis and degradation show, however, interesting differences that have conditioned the evolution of gene regulatory mechanisms. Here, we discuss recent genome-wide methods for determining mRNA half-lives in eukaryotes. We also review pre- and posttranscriptional regulons that coordinate the fate of functionally related mRNAs by using protein- or RNA-based trans factors. Some of these factors can regulate both transcription and decay rates, thereby maintaining proper mRNA homeostasis during eukaryotic cell life.

Study of β-defensin polymorphisms in Valle del Belice dairy sheep

2009

The aim of this work was to sequence the exons of β-defensin 1 and 2 genes (SBD1 and SBD2) in Valle del Belice dairy sheep in order to identify polymorphisms. The study was conducted on 60 samples from three flocks. Six SNPs were identified: two in SBD1 and four in SBD2. Both genes consist of two exons and one intron. In SBD1 gene, SNPs were found only in the exon 2, whereas in SBD2, SNPs were detected in both exons. In both genes, SNPs were located in the coding regions and in the 3'-UTR. The SNP in SBD2 located at position 1659 determined a change in the protein sequence. Further studies will be necessary to investigate if the amino acid change modifies the biological function of the…

Redox regulation of genome stability by effects on gene expression, epigenetic pathways and DNA damage/repair

2015

Reactive oxygen and nitrogen species (e.g. H2O2, nitric oxide) confer redox regulation of essential cellular signaling pathways such as cell differentiation, proliferation, migration and apoptosis. In addition, classical regulation of gene expression or activity, including gene transcription to RNA followed by translation to the protein level, by transcription factors (e.g. NF-κB, HIF-1α) and mRNA binding proteins (e.g. GAPDH, HuR) is subject to redox regulation. This review will give an update of recent discoveries in this field, and specifically highlight the impact of reactive oxygen and nitrogen species on DNA repair systems that contribute to genomic stability. Emphasis will be placed …

Characteristics and definition and characterization of new Valencian urban areas

2014

La expansión urbanística, junto con la generalización de los procesos de descentralización residencial y económica, ha conducido a un nuevo modelo de ciudad dispersa caracterizado por la dificultad de establecer sus límites precisos. Utilizando un índice de densidad de ejes viarios procedente de una fuente comercial, y por tanto fácilmente actualizable, se ha delimitado el fenómeno urbano en la Comunidad Valenciana. Se discute la utilidad de la metodología y su capacidad para captar el hecho urbano a partir del contraste con la cartografía de usos del suelo de Corine. Urban expansion, along with the generalization of the processes of residential and economic decentralization has led to a ne…

Strategic Environmental Assessment: Integrating Landscape and Urban Planning

2016

This book explores the opportunities offered by Strategic Environmental Assessment in the context of guaranteeing the synchronized integration of landscape (in all its aspects) within urban plans, thereby helping to overcome the constraints of rigidly framed, sector-focused laws and a purely aesthetic concept of landscape. In pursuit of this goal, various scholars have previously attempted to construct arrays of indicators relating to the different conceptions of “landscape”. This book critically examines the most complete proposals of this nature, systematizing and comparing them and, finally, offering some guidelines with respect to their codification within specific application protocols…

España inacabada. Organización territorial del Estado, autonomía política y reconocimiento de la diversidad nacional

2021

S’han complert més de tres dècades de vigència de la Constitució de 1978 i, per tant, ja es disposa de prou perspectiva per analitzar el grau d’eficàcia d’un model d’Estat, per alguns, gairebé federal i, per a uns altres, senzillament molt descentralitzat. D’altra banda, a Espanya segueix plenament obert el debat sobre Espanya. Sigui quina sigui l’opinió, la veritat és que el nostre antic problema consumeix una gran part de les energies col·lectives, condiciona àmpliament l’agenda política, genera notables tensions socials i projecta ombres d’incertesa respecte al futur. En aquest treball, s’hi presenta un balanç de les dues qüestions. Després d’oferir un resum breu del procés de construcci…