Cretaceous origin and repeated tertiary diversification of the redefined butterflies

Although the taxonomy of the ca 18 000 species of butterflies and skippers is well known, the family-level relationships are still debated. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the superfamilies Papilionoidea, Hesperioidea and Hedyloidea to date based on morphological and molecular data. We reconstructed their phylogenetic relationships using parsimony and Bayesian approaches. We estimated times and rates of diversification along lineages in order to reconstruct their evolutionary history. Our results suggest that the butterflies, as traditionally understood, are paraphyletic, with Papilionidae being the sister-group to Hesperioidea, Hedyloidea and all other butterflies. Hence, the families in the current three superfamilies should be placed in a single superfamily Papilionoidea. In addition, we find that Hedylidae is sister to Hesperiidae, and this novel relationship is supported by two morphological characters. The families diverged in the Early Cretaceous but diversified after the Cretaceous-Palaeogene event. The diversification of butterflies is characterized by a slow speciation rate in the lineage leading to Baronia brevicornis, a period of stasis by the skippers after divergence and a burst of diversification in the lineages leading to Nymphalidae, Riodinidae and Lycaenidae.     

Molecular cytogenetic studies of the “Xanthocephalum group” (Asteraceae)

Fourteen North American members of the “Xanthocephalum group” were studied by classical and molecular cytogenetics. Location and number of rDNA sites were determined by FISH. For the 5S rDNA, a probe was obtained from Prionopsis ciliata. Most species were diploid (2n?=?12), although Isocoma menziesii, Grindelia hirsutula, G. robusta, both varieties of G. stricta, and one population of G. camporum were tetraploid (2n?=?24). Diploid Grindelia and Prionopsis ciliata were 5m?+?1sm, tetraploids 10m?+?2sm, except G. hirsutula (8m?+?4sm), and Isocoma and Olivaea 6m?+?2sm and 3m?+?3sm, respectively. Most species had satellites on the short arms of m pairs: two in tetraploids and P. ciliata and one in diploids. Satellites were associated with two CMA⁺/DAPI^? bands in diploid species and four bands in tetraploids and in P. ciliata. rDNA loci (two in diploids to four in tetraploids) may be indicative of ploidy level. Grindelia tetraploids could have originated recently by autopolyploidy. Chromosome duplication was followed by modifications in the genome structure, resulting in higher heterochromatin amounts not associated with NORs. There is only one 5S site per basic genome in para or pericentromeric regions. Although not always large, chromosome variation has accompanied the evolutionary divergence of the taxa studied.     

Filling biodiversity gaps: benthic hydroids from the Bellingshausen Sea (Antarctica)

The Bellingshausen Sea constitutes the third largest sea in the Southern Ocean, though it is widely recognized as one of the less-studied Antarctic areas. To reduce this lack of knowledge, a survey to study the biodiversity of its marine benthic communities was carried out during the Bentart 2003 and Bentart 2006 Spanish Antarctic expeditions. The study of the hydroid collection has provided 27 species, belonging to ten families and 15 genera. Twenty-one out of the 27 species constitute new records for the Bellingshausen Sea, raising the total number of known species to 37, as also do nine out of the 15 genera. Candelabrum penola, Lafoea annulata, and Staurotheca juncea are recorded for the second time. Most species belong to Leptothecata. Sertulariidae with 13 species (48%) is by far the most speciose family, and Symplectoscyphus with seven species (26%), including S. bellingshauseni sp. nov. and S. hesperides sp. nov., the most diverse genus. Considering the whole benthic hydroid fauna of the Bellingshausen Sea, 18 species (69%) are endemic to Antarctic waters, either with a circum-Antarctic (12 species, 46%) or West Antarctic (6 species, 23%) distribution, 23 (88%) are restricted to Antarctic or Antarctic/sub-Antarctic waters, and only three species have a wider distribution. Bellingshausen Sea hydroid fauna is composed of a relatively high diversity of typical representatives of the Antarctic benthic hydroid fauna, though with a surprisingly low representation of some of the most diverse and widespread Antarctic genera (Oswaldella and Schizotricha), what could be related to the fact that its shelf-inhabiting hydroid fauna remains practically unknown.     

Genetic diversity and structure of wild populations of the tropical dry forest tree Jacaratia mexicana (Brassicales: Caricaceae) at a local scale in Mexico

The tropical dry forest is a greatly endangered ecosystem, from which Jacaratia mexicana is a native tree. With the aim to assess the levels of genetic variation and population structure, four wild populations of J. mexicana were studied in the Sierra de Huautla Biosphere Reserve, Morelos, Mexico. For this, DNA was extracted from 159 individuals and were amplified with six random primers using the Random Amplified Polymorphic DNA (RAPD). A total of 54 bands were obtained, of which 50 (92.6%) were polymorphic. The total genetic diversity found within the four populations was 0.451 when estimated by Shannon's index. An AMOVA analysis showed that 84% of the total genetic variation was found within populations and 16% was among populations. The UPGMA dendrogram showed that all individuals from one of the populations (Huaxtla) formed one distinct genetic group, while the rest of the individuals did not cluster according to population. A Mantel test did not show an association between genetic and geographical distances among populations (r=0.893, p=0.20). A Bayesian cluster analysis performed with STRUCTURE, showed that the most probable number of genetic groups in the data was four (K=4), and confirmed the distinctness of Huaxtla population. Our results showed that important genetic differentiation among populations can occur even at this small geographic scale and this has to be considered in conservation actions for this genetic resource.     

The structures and inhibitory effects of Buame [N-(3-hydroxy-1,3,5(10)-estratrien-17β-yl)-butylamine] and Diebud [N,N'-bis-(3-hydroxy-1,3,5(10)-estratrien-17β-yl)-1,4-butanediamine] on platelet aggregation

Compounds with estrogenic effects that also inhibit platelet aggregation might be useful in reducing thrombotic events associated with estrogenic therapy. In this study, two aminoestrogens, Buame [N-(3-hydroxy-1,3,5(10)-estratrien-17β-yl)-butylamine] and Diebud [N,N'-bis-(3-hydroxy-1,3,5(10)-estratrien-17β-yl)-1,4-butanediamine], were synthesized and characterized using common analytical methods and spectrophotometric analyses. The location and orientation of these molecules on the estrogenic receptor α (ERα) were also evaluated. Platelet inhibitory effects were elucidated ADP-induced platelet aggregation and ADP- and collagen-induced ATP release. Molecular docking demonstrated that Buame can reach and bind to the ERα in the ligand binding domain (LBD) similar to 17β-estradiol (co-crystallized ligand). On the other hand, Diebud binds only to the surface of ERα due to its high molecular volume compared to 17β-estradiol and Buame.     

The impact of Converso Jews on the genomes of modern Latin Americans

Modern day Latin America resulted from the encounter of Europeans with the indigenous peoples of the Americas in 1492, followed by waves of migration from Europe and Africa. As a result, the genomic structure of present day Latin Americans was determined both by the genetic structure of the founding populations and the numbers of migrants from these different populations. Here, we analyzed DNA collected from two well-established communities in Colorado (33 unrelated individuals) and Ecuador (20 unrelated individuals) with a measurable prevalence of the BRCA1 c.185delAG and the GHR c.E180 mutations, respectively, using Affymetrix Genome-wide Human SNP 6.0 arrays to identify their ancestry. These mutations are thought to have been brought to these communities by Sephardic Jewish progenitors. Principal component analysis and clustering methods were employed to determine the genome-wide patterns of continental ancestry within both populations using single nucleotide polymorphisms, complemented by determination of Y-chromosomal and mitochondrial DNA haplotypes. When examining the presumed European component of these two communities, we demonstrate enrichment for Sephardic Jewish ancestry not only for these mutations, but also for other segments as well. Although comparison of both groups to a reference Hispanic/Latino population of Mexicans demonstrated proximity and similarity to other modern day communities derived from a European and Native American two-way admixture, identity-by-descent and Y-chromosome mapping demonstrated signatures of Sephardim in both communities. These findings are consistent with historical accounts of Jewish migration from the realms that comprise modern Spain and Portugal during the Age of Discovery. More importantly, they provide a rationale for the occurrence of mutations typically associated with the Jewish Diaspora in Latin American communities.     

Expression of the maize ZmGF14-6 gene in rice confers tolerance to drought stress while enhancing susceptibility to pathogen infection

14-3-3 proteins are found in all eukaryotes where they act as regulators of diverse signalling pathways associated with a wide range of biological processes. In this study the functional characterization of the ZmGF14-6 gene encoding a maize 14-3-3 protein is reported. Gene expression analyses indicated that ZmGF14-6 is up-regulated by fungal infection and salt treatment in maize plants, whereas its expression is down-regulated by drought stress. It is reported that rice plants constitutively expressing ZmGF14-6 displayed enhanced tolerance to drought stress which was accompanied by a stronger induction of drought-associated rice genes. However, rice plants expressing ZmGF14-6 either in a constitutive or under a pathogen-inducible regime showed a higher susceptibility to infection by the fungal pathogens Fusarium verticillioides and Magnaporthe oryzae. Under infection conditions, a lower intensity in the expression of defence-related genes occurred in ZmGF14-6 rice plants. These findings support that ZmGF14-6 positively regulates drought tolerance in transgenic rice while negatively modulating the plant defence response to pathogen infection. Transient expression assays of fluorescently labelled ZmGF14-6 protein in onion epidermal cells revealed a widespread distribution of ZmGF14-6 in the cytoplasm and nucleus. Additionally, colocalization experiments of fluorescently labelled ZmGF14-6 with organelle markers, in combination with cell labelling with the endocytic tracer FM4-64, revealed a subcellular localization of ZmGF14-6 in the early endosomes. Taken together, these results improve our understanding of the role of ZmGF14-6 in stress signalling pathways, while indicating that ZmGF14-6 inversely regulates the plant response to biotic and abiotic stresses.     

Comparison of two techniques for the morphometry study on gilthead seabream (Sparus aurata) spermatozoa and evaluation of changes induced by cryopreservation

The development of powerful software has made possible spermatozoa morphology studies. However, some problems have emerged in relation to protocol standardization to compare results from different laboratories. This study was carried out to compare two techniques commonly used (staining vs phase contrast technique) for the morphometry study of gilthead sea bream spermatozoa using an integrated sperm analysis system (ISAS). Spermatozoa morphometry values were significantly affected by the technique used, and phase contrast technique was found to be the more accurate method, showing lower coefficients of variation on spermatozoa morphometry parameters measurements. Moreover, it has been shown that cryopreservation process produces damage in gilthead sea bream spermatozoa, causing negative effects in sperm parameters as spermatozoa morphometry (a decrease in cell volume), motility (from 95 to 68% motile cells) and viability (from 95 to 87% of live cells), being the addition of freezing medium containing cryoprotectant (DMSO) an important factor that caused the morphometry changes.