Riding the wave: the SINE-specific V highly conserved domain spread into mammalian genomes exploiting the replication burst of MER6 DNA transposon.

Transposable elements are widely distributed within genomes where they may significantly impact their evolution and cell functions. Short interspersed elements (SINEs) are non-autonomous, fast-evolving elements, but some of them carry a highly conserved domain (HCD), whose sequence remained substantially unchanged throughout the metazoan evolution. SINEs carrying the HCD called V are absent in amniote genomes, but V-like sequences were found within the miniature inverted-repeat transposable element (MITE) MER6 in Homo sapiens. In the present work, the genomic distribution and evolution of MER6 are investigated, in order to reconstruct the origin of human V domain and to envisage its possible functional role. The analysis of 85 tetrapod genomes revealed that MER6 and its variant MER6A are found in primates, while only the MER6A variant was found in bats and eulipotyphlans. These MITEs appeared no longer active, in line with literature data on mammalian DNA transposons. Moreover, they appeared to have originated from a Mariner element found in turtles and from a V-SINE from bony fishes. MER6 insertions were found within genes and conserved in mRNAs: in line with previous hypothesis on functional role of HCDs, the MER6 V domain may be important for cell function also in mammals

Antichi versi greci. Considerazioni sullo statuto documentario delle fonti metriche

Nella dinamica necessariamente revisionista della ricerca scientifica, i risultati di chi ci ha preceduto sono un’acquisizione di fronte alla quale conservare un equilibrato atteggiamento interlocutorio. In questa luce, l’esigenza di una verifica dei fondamenti metodologici della dottrina metrica moderna sugli antichi versi greci consente di rileggere con rinnovato interesse la dottrina antica. La quale, una volta che sia correttamente inquadrata e spiegata, si mostra strumento efficace per comprendere e ricostruire i documenti poetici che restano. E anche la querelle tra teoria moderna e teoria antica sui metri greci si può configurare come uno di quei casi in cui, per usare le parole dell’insigne filologo G. Thomas Tanselle, "chronology is not sinonymous with progress"

La voce delle Erinni in Aesch., Eum. vv. 117-139

ItAttraverso l'analisi della struttura formale e metrico-ritmica dei vv. 117-139, e un approfondimento di carattere linguistico sui suoni emessi, come risulta dalle didascalie sceniche nel mediceo, dalle Erinni nel loro 'dialogare' con l'ombra di Clitemestra, questo studio evidenzia i caratteri di novità drammaturgica e musicale esibiti dal canto di apertura delle Eumenidi.EnThrough the analysis of the formal, metric, and rhythmic structure of the vv. 117-139, and an in-depth study of the linguistic nature of the sounds emitted, as shown by the didascalies in the medicean codex, by the Erinyes in their 'dialogue' with the shadow of Clytemestra, this study highlights the dramaturgical and musical novelties exhibited in the song of opening of the Eumenides

Gunshot wound without entrance hole: where is the trick? - a case report and review of the literature

The presence at CT scan of more retained bullets than expected could be a very difficult interpretation challenge in the early management of gunshot wounds. The modern non operative management of haemodinamically stable patients without peritonitis requires that the trajectory of the bullet is clearly recognized. This clinical case reporting of a gunshot wound without evident entry hole, allows to discuss the diagnostic and therapeutic implications in the management of gunshot wounds cases with atypical entry and/or exit holes

Evolutionary-new centromeres preferentially emerge within gene deserts

A study identifying genomic restructuring and the absence of genes as conditions permissive for the seeding of new centromeres in primate

Chromosome positioning in interphase nuclei of hematopoietic stem cell and myeloid precursor

Human myelopoiesis is an intriguing biological process during which multipotent stem cells limit their differentiation potential generating precursors that evolve into terminally differentiated cells. The differentiation process is correlated with differential gene expression and changes in nuclear architecture. In interphase, chromosomes are distinct entities known as chromosome territories and they show a radial localization that could result in a constrain of inter-homologous distance. This element plays a role in genome stability and gene expression. Here, we provide the first experimental evidence of 3D chromosomal arrangement considering two steps of human normal myelopoiesis. Specifically, multicolor 3D-FISH and 3D image analysis revealed that, in both normal human hematopoietic stem cells and myelod precursors CD14-, chromosomal position is correlated with gene density. However, we observed that inter-homologue distances are totally different during differentiation. This could be associated with differential gene expression that we found comparing the two cell types. Our results disclose an unprecedented framework relevant for deciphering the genomic mechanisms at the base of normal human myelopoiesis

Evolutionary history of chromosome 11 featuring four distinct centromere repositioning events in Catarrhini.

Abstract Panels of BAC clones used in FISH experiments allow a detailed definition of chromosomal marker arrangement and orientation during evolution. This approach has disclosed the centromere repositioning phenomenon, consisting in the activation of a novel, fully functional centromere in an ectopic location, concomitant with the inactivation of the old centromere. In this study, appropriate panels of BAC clones were used to track the chromosome 11 evolutionary history in primates and nonprimate boreoeutherian mammals. Chromosome 11 synteny was found to be highly conserved in both primate and boreoeutherian mammalian ancestors. Amazingly, we detected four centromere repositioning events in primates (in Old World monkeys, in gibbons, in orangutans, and in the Homo–Pan–Gorilla (H-P-G) clade ancestor), and one in Equidae. Both H-P-G and Lar gibbon novel centromeres were flanked by large duplicons with high sequence similarity. Outgroup species analysis revealed that this duplicon was absent in phylogenetically more distant primates. The chromosome 11 ancestral centromere was probably located near the HSA11q telomere. The domain of this inactivated centromere, in humans, is almost devoid of segmental duplications. An inversion occurred in chromosome 11 in the common ancestor of H-P-G. A large duplicon, again absent in outgroup species, was found located adjacent to the inversion breakpoints. In Hominoidea, almost all the five largest duplicons of this chromosome appeared involved in significant evolutionary architectural changes