Growth form evolution and hybridization in (Asteraceae) from the high equatorial Andes.

Changes in growth forms frequently accompany plant adaptive radiations, including páramo-a high-elevation treeless habitat type of the northern Andes. We tested whether diverse group of inhabiting montane forests and páramo represented such growth form changes. We also investigated the role of Andean geography and environment in structuring genetic variation of this group.

Niche shifts and range expansions along cordilleras drove diversification in a high-elevation endemic plant genus in the tropical Andes.

The tropical Andes represent one of the world's biodiversity hot spots, but the evolutionary drivers generating their striking species diversity still remain poorly understood. In the treeless high-elevation Andean environments, Pleistocene glacial oscillations and niche differentiation are frequently hypothesized diversification mechanisms; however, sufficiently densely sampled population genetic data supporting this are still lacking. Here, we reconstruct the evolutionary history of Loricaria (Asteraceae), a plant genus endemic to the Andean treeless alpine zone, based on comprehensive population-level sampling of 289 individuals from 67 populations across the entire distribution ranges of its northern Andean species.

CRE promoter sites modulate alternative splicing via p300-mediated histone acetylation.

Histone acetylation modulates alternative splicing of several hundred genes. Here, we tested the role of the histone acetyltransferase p300 in alternative splicing and showed that knockdown of p300 promotes inclusion of the fibronectin (FN1) alternative EDB exon. p300 associates with CRE sites in the promoter via the CREB transcription factor.

The C-terminal domain of Brd2 is important for chromatin interaction and regulation of transcription and alternative splicing.

Brd2 is a member of the bromodomain extra terminal (BET) protein family, which consists of four chromatin-interacting proteins that regulate gene expression. Each BET protein contains two N-terminal bromodomains, which recognize acetylated histones, and the C-terminal protein-protein interaction domain. Using a genome-wide screen, we identify 1450 genes whose transcription is regulated by Brd2.

Bringing together evolution on serpentine and polyploidy: spatiotemporal history of the diploid-tetraploid complex of Knautia arvensis (Dipsacaceae).

Polyploidization is one of the leading forces in the evolution of land plants, providing opportunities for instant speciation and rapid gain of evolutionary novelties. Highly selective conditions of serpentine environments act as an important evolutionary trigger that can be involved in various speciation processes. Whereas the significance of both edaphic speciation on serpentine and polyploidy is widely acknowledged in plant evolution, the links between polyploid evolution and serpentine differentiation have not yet been examined.

Plasmids carrying blaCTX-M-1 and qnr genes in Escherichia coli isolates from an equine clinic and a horseback riding centre.

Objectives: The aim of this study was to determine the occurrence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli at an equine clinic and a horseback riding centre, and to discuss the impact of antimicrobial treatment on resistance selection.

Methods: Faeces from horses, environmental smears and flies were sampled at both the clinic and riding centre. Staff at the equine clinic were also examined.

Histone deacetylase activity modulates alternative splicing.

There is increasing evidence to suggest that splicing decisions are largely made when the nascent RNA is still associated with chromatin. Here we demonstrate that activity of histone deacetylases (HDACs) influences splice site selection. Using splicing-sensitive microarrays, we identified ∼700 genes whose splicing was altered after HDAC inhibition.