Kdm1a safeguards the topological boundaries of PRC2-repressed genes and prevents aging-related euchromatinization in neurons.

Kdm1a is a histone demethylase linked to intellectual disability with essential roles during gastrulation and the terminal differentiation of specialized cell types, including neurons, that remains highly expressed in the adult brain. To explore Kdm1a's function in adult neurons, we develop inducible and forebrain-restricted Kdm1a knockouts. By applying multi-omic transcriptome, epigenome and chromatin conformation data, combined with super-resolution microscopy, we find that Kdm1a elimination causes the neuronal activation of nonneuronal genes that are silenced by the polycomb repressor complex and interspersed with active genes. Functional assays demonstrate that the N-terminus of Kdm1a contains an intrinsically disordered region that is essential to segregate Kdm1a-repressed genes from the neighboring active chromatin environment. Finally, we show that the segregation of Kdm1a-target genes is weakened in neurons during natural aging, underscoring the role of Kdm1a safeguarding neuronal genome organization and gene silencing throughout life.

Illuminating the Mysteries of the Smallest Birds: Hummingbird Population Health, Disease Ecology, and Genomics.

Hummingbirds share biologically distinctive traits: sustained hovering flight, the smallest bird body size, and high metabolic rates fueled partially by nectar feeding that provides pollination to plant species. Being insectivorous and sometimes serving as prey to larger birds, they fulfill additional important ecological roles. Hummingbird species evolved and radiated into nearly every habitat in the Americas, with a core of species diversity in South America. Population declines of some of their species are increasing their risk of extinction. Threats to population health and genetic diversity are just beginning to be identified, including diseases and hazards caused by humans. We review the disciplines of population health, disease ecology, and genomics as they relate to hummingbirds. We appraise knowledge gaps, causes of morbidity and mortality including disease, and threats to population viability. Finally, we highlight areas of research need and provide ideas for future studies aimed at facilitating hummingbird conservation.

Identification and distribution of a fungal endosymbiotic Alternaria species (Alternaria section Undifilum sp.) in Astragalus garbancillo tissues.

Plants belonging to the genera Astragalus, Oxytropis, Ipomoea, Sida, and Swainsona often contain the toxin swainsonine (SW) produced by an associated fungal symbiont. Consumption of SW-containing plants causes a serious neurological disorder in livestock, which can be fatal. In this study, a fungal endophyte, Alternaria section Undifilum, was identified in Astragalus garbancillo seeds, using polymerase chain reaction (PCR) followed by direct sequencing. In seeds, the SW concentrations were about 4 times higher than in other parts of the plant. Furthermore, microscopic examination demonstrated that the fungus mycelium grows inside the petioles and stems, on the outer surface and inside the mesocarp of the fruit, in the mesotesta and endotesta layers of the seed coat, and inside the endosperm of the seeds. Our results support the notion that the SW-producing fungus is vertically transmitted in the host plant A. garbancillo.

Springing forward: Migrating songbirds catch up with the start of spring in North America.

In temperate regions, the annual pattern of spring onset can be envisioned as a 'green wave' of emerging vegetation that moves across continents from low to high latitudes, signifying increasing food availability for consumers. Many herbivorous migrants 'surf' such resource waves, timing their movements to exploit peak vegetation resources in early spring. Although less well studied at the individual level, secondary consumers such as insectivorous songbirds can track vegetation phenology during migration as well. We hypothesized that four species of ground-foraging songbirds in eastern North America-two warblers and two thrushes-time their spring migrations to coincide with later phases of vegetation phenology, corresponding to increased arthropod prey, and predicted they would match their migration rate to the green wave but trail behind it rather than surfing its leading edge. We further hypothesized that the rate at which spring onset progresses across the continent influences bird migration rates, such that individuals adjust migration timing within North America to phenological conditions they experience en route. To test our hypotheses, we used a continent-wide automated radio telemetry network to track individual songbirds on spring migration between the U.S. Gulf Coast region and northern locations closer to their breeding grounds. We measured vegetation phenology using two metrics of spring onset, the spring index first leaf date and the normalized difference vegetation index (NDVI), then calculated the rate and timing of spring onset relative to bird detections. All individuals arrived in the southeastern United States well after local spring onset. Counter to our expectations, we found that songbirds exhibited a 'catching up' pattern: Individuals migrated faster than the green wave of spring onset, effectively closing in on the start of spring as they approached breeding areas. While surfing of resource waves is a well-documented migration strategy for herbivorous waterfowl and ungulates, individual songbirds in our study migrated faster than the green wave and increasingly caught up to its leading edge en route. Consequently, songbirds experience a range of vegetation phenophases while migrating through North America, suggesting flexibility in their capacity to exploit variable resources in spring.

En las regiones templadas, el patrón anual de inicio de la primavera puede concebirse como una "ola verde" de vegetación emergente que se desplaza por los continentes desde las latitudes bajas a las altas, lo que significa una mayor disponibilidad de alimento para los consumidores. Muchos herbívoros migratorios "surfean" estas olas de recursos, programando sus movimientos para aprovechar los picos de vegetación a principios de primavera. Aunque menos estudiados a nivel de individuo, los consumidores secundarios, como las aves terrestres insectívoras, también pueden seguir la fenología de la vegetación durante la migración. Hipotetizamos es que cuatro especies de aves terrestres que se alimentan en el suelo en el este de Norteamérica - dos reinitas y dos zorzales - programan sus migraciones primaverales para que coincidan con las fases más tardías de la fenología de la vegetación, que se corresponden con un aumento de artrópodos, y predijimos que sincronizarian su ritmo de migración con la ola verde, pero que irían detrás de ella en lugar de surfear su borde delantero. También hipotetizamos que el ritmo al que avanza la primavera en el continente influye en las tasas de migración de las aves, de modo que los individuos ajustan la fecha de migración dentro de Norteamérica a las condiciones fenológicas que experimentan en ruta. Para comprobar nuestras hipótesis, utilizamos una red automatizada de radiotelemetría a escala continental para seguir individuos en su migración primaveral entre la región de la costa del Golfo de EEUU y las localidades septentrionales más cercanas a sus zonas de cría. Medimos la fenología de la vegetación utilizando dos métricas del inicio de la primavera, el índice de la fecha de la primera hoja primaveral y el índice de vegetación de diferencia normalizada (NDVI), luego calculamos la tasa y el tiempo de la aparaciòn de la primavera relativo a las detecciones de aves. Todos los individuos llegaron al sureste de EEUU bastante después del inicio de la primavera local. Contrario a nuestras expectativas, descubrimos que las aves terrestres mostraron un patrón de Carrera para "ponerse al día": los individuos migraron frente a la ola verde del inicio de la primavera, acercándose efectivamente al inicio de la primavera a medida que llegaban a las zonas de cría. Mientras que el surfing de las olas de recursos es una estrategia migratoria bien documentada para las aves acuáticas herbívoras y los ungulados, los individuos de aves terrestres de nuestro estudio migraron más rápido que la ola verde y alcanzaron cada vez más el borde delantero en ruta. En consecuencia, las aves terrestres experimentan una serie de fases fenológicas de la vegetación mientras migran a través de Norteamérica, lo que sugiere flexibilidad en su capacidad para explotar recursos variables en primavera.

Microscopical Analysis of Autofluorescence as a Complementary and Useful Method to Assess Differences in Anatomy and Structural Distribution Underlying Evolutive Variation in Loss of Seed Dispersal in Common Bean.

The common bean has received attention as a model plant for legume studies, but little information is available about the morphology of its pods and the relation of this morphology to the loss of seed dispersal and/or the pod string, which are key agronomic traits of legume domestication. Dehiscence is related to the pod morphology and anatomy of pod tissues because of the weakening of the dorsal and ventral dehiscence zones and the tensions of the pod walls. These tensions are produced by the differential mechanical properties of lignified and non-lignified tissues and changes in turgor associated with fruit maturation. In this research, we histologically studied the dehiscence zone of the ventral and dorsal sutures of the pod in two contrasting genotypes for the dehiscence and string, by comparing different histochemical methods with autofluorescence. We found that the secondary cell wall modifications of the ventral suture of the pod were clearly different between the dehiscence-susceptible and stringy PHA1037 and the dehiscence-resistant and stringless PHA0595 genotypes. The susceptible genotype had cells of bundle caps arranged in a more easily breakable bowtie knot shape. The resistant genotype had a larger vascular bundle area and larger fibre cap cells (FCCs), and due to their thickness, the external valve margin cells were significantly stronger than those from PHA1037. Our findings suggest that the FCC area, and the cell arrangement in the bundle cap, might be partial structures involved in the pod dehiscence of the common bean. The autofluorescence pattern at the ventral suture allowed us to quickly identify the dehiscent phenotype and gain a better understanding of cell wall tissue modifications that took place along the bean's evolution, which had an impact on crop improvement. We report a simple autofluorescence protocol to reliably identify secondary cell wall organization and its relationship to the dehiscence and string in the common bean.

Evaluation of a biobased polycarbonate interpenetrated network in a dental resin composite.

Silanization of filler particles in a dental resin composite is achieved by the formation of Si-O-Si bonds, however, these bonds are especially vulnerable to hydrolysis because this covalent bond has a significant ionic character due to the electronegativity differences between the atoms. The objective of this study was to evaluate the use of an interpenetrated network (IPN) as alternative of silanization reaction and to assess its effect in selected properties of experimental photopolymerizable resin composites. The interpenetrate network was obtained during the photopolymerization reaction of organic matrix (BisGMA/TEGDMA) with a biobased polycarbonate. Its characterization was performed via FTIR, flexural strength, flexural modulus, depth of cure, sorption water and solubility. A resin composite formulated with non-silanized filler particles was used as control. The IPN with a biobased polycarbonate was successfully synthesized. The results showed that the IPN based resin composite had higher values of flexural strength, flexural modulus, and degree of double bond conversion than the control (p < 0.05). Polymerization shrinkage, water sorption and solubility were statistically significantly lower than the control resin (p < 0.05). Finally, this study shows there were no statistically significant differences for the biocompatibility outcomes (p > 0.05). The biobased IPN replaces the silanization reaction in resin composites, improving physical and chemical properties. Therefore, IPN with a biobased polycarbonate could be potentially useful in the formulation of dental resin composites.

Flower structure, anatomy, and sexuality of Chrysophyllum gonocarpum (Sapotaceae).

The Sapotaceae are a significant component of the humid forests of the Neotropics and have many species of economic interest. Chrysophyllum gonocarpum is one of them and its edible fruits have currently acquired a high commercial value. Since there are no studies that cover its floral anatomy and elucidate its sexual system, the objective of the present study is to describe these aspects based on field observations and a detailed anatomical analysis of their flowers. Conventional techniques of plant anatomy are implemented. The results indicate that the species presents cryptic dioecy, showing specimens with morphologically and functionally pistillate flowers (with reduced staminodes), and trees with morphologically hermaphrodite and functionally staminate flowers. In addition, data on floral nectaries and laticiferous are provided.

Estimation of the full shape of the crystalline lens in-vivo from OCT images using eigenlenses.

Quantifying the full 3-D shape of the human crystalline lens is important for improving intraocular lens power or sizing calculations in treatments of cataract and presbyopia. In a previous work we described a novel method for the representation of the full shape of the ex vivo crystalline lens called eigenlenses, which proved more compact and accurate than compared state-of-the art methods of crystalline lens shape quantification. Here we demonstrate the use of eigenlenses to estimate the full shape of the crystalline lens in vivo from optical coherence tomography images, where only the information visible through the pupil is available. We compare the performance of eigenlenses with previous methods of full crystalline lens shape estimation, and demonstrate an improvement in repeatability, robustness and use of computational resources. We found that eigenlenses can be used to describe efficiently the crystalline lens full shape changes with accommodation and refractive error.

SWI/SNF complexes in hematological malignancies: biological implications and therapeutic opportunities.

Hematological malignancies are a highly heterogeneous group of diseases with varied molecular and phenotypical characteristics. SWI/SNF (SWItch/Sucrose Non-Fermentable) chromatin remodeling complexes play significant roles in the regulation of gene expression, being essential for processes such as cell maintenance and differentiation in hematopoietic stem cells. Furthermore, alterations in SWI/SNF complex subunits, especially in ARID1A/1B/2, SMARCA2/4, and BCL7A, are highly recurrent across a wide variety of lymphoid and myeloid malignancies. Most genetic alterations cause a loss of function of the subunit, suggesting a tumor suppressor role. However, SWI/SNF subunits can also be required for tumor maintenance or even play an oncogenic role in certain disease contexts. The recurrent alterations of SWI/SNF subunits highlight not only the biological relevance of SWI/SNF complexes in hematological malignancies but also their clinical potential. In particular, increasing evidence has shown that mutations in SWI/SNF complex subunits confer resistance to several antineoplastic agents routinely used for the treatment of hematological malignancies. Furthermore, mutations in SWI/SNF subunits often create synthetic lethality relationships with other SWI/SNF or non-SWI/SNF proteins that could be exploited therapeutically. In conclusion, SWI/SNF complexes are recurrently altered in hematological malignancies and some SWI/SNF subunits may be essential for tumor maintenance. These alterations, as well as their synthetic lethal relationships with SWI/SNF and non-SWI/SNF proteins, may be pharmacologically exploited for the treatment of diverse hematological cancers.

Pulsed Electric Fields (PEF) and Accelerated Solvent Extraction (ASE) for Valorization of Red (Aristeus antennatus) and Camarote (Melicertus kerathurus) Shrimp Side Streams: Antioxidant and HPLC Evaluation of the Carotenoid Astaxanthin Recovery.

Shrimp side streams represent an important natural source of astaxanthin. Optimization of the astaxanthin extraction process from shrimp side streams is of great importance for the valorization of crustacean side streams and the development of astaxanthin-related products. The combined and independent effects of two innovative extraction technologies (pulsed electric fields (PEFs) and accelerated solvent extraction (ASE)) alone and/or combined in a sequential step, using two different solvents on astaxanthin extraction from two shrimp species, were evaluated. Astaxanthin content in the extracts of shrimp side streams was determined by both spectrophotometric and HPLC assays, being the determination of the carotenoid profiles performed by HPLC analysis. Compared to a solvent extraction control procedure, the astaxanthin content was increased after ASE and PEF treatments, for both shrimp species, independently of the solvent used. The highest recovery (585.90 µg/g) was obtained for the species A. antennatus, with the solvent DMSO when PEF and ASE were combined, while the increase in antioxidant capacity varied depending on the solvent used. HPLC analysis of the samples revealed the presence of unesterified (all-E) astaxanthin, four unesterified Z isomers of astaxanthin and many unresolved astaxanthin esters. Both technologies are useful tools to recover antioxidant valuable carotenoids such as astaxanthin from shrimp side streams.

Decoding Gene Expression Signatures Underlying Vegetative to Inflorescence Meristem Transition in the Common Bean.

The tropical common bean (Phaseolus vulgaris L.) is an obligatory short-day plant that requires relaxation of the photoperiod to induce flowering. Similar to other crops, photoperiod-induced floral initiation depends on the differentiation and maintenance of meristems. In this study, the global changes in transcript expression profiles were analyzed in two meristematic tissues corresponding to the vegetative and inflorescence meristems of two genotypes with different sensitivities to photoperiods. A total of 3396 differentially expressed genes (DEGs) were identified, and 1271 and 1533 were found to be up-regulated and down-regulated, respectively, whereas 592 genes showed discordant expression patterns between both genotypes. Arabidopsis homologues of DEGs were identified, and most of them were not previously involved in Arabidopsis floral transition, suggesting an evolutionary divergence of the transcriptional regulatory networks of the flowering process of both species. However, some genes belonging to the photoperiod and flower development pathways with evolutionarily conserved transcriptional profiles have been found. In addition, the flower meristem identity genes APETALA1 and LEAFY, as well as CONSTANS-LIKE 5, were identified as markers to distinguish between the vegetative and reproductive stages. Our data also indicated that the down-regulation of the photoperiodic genes seems to be directly associated with promoting floral transition under inductive short-day lengths. These findings provide valuable insight into the molecular factors that underlie meristematic development and contribute to understanding the photoperiod adaptation in the common bean.

Transcriptome Dynamics of Rooting Zone and Leaves during In Vitro Adventitious Root Formation in Eucalyptus nitens.

Wood properties and agronomic traits associated with fast growth and frost tolerance make Eucalyptus nitens a valuable forest alternative. However, the rapid age-related decline in the adventitious root (AR) formation (herein, meaning induction, initiation, and expression stages) limits its propagation. We analyzed transcriptomic profile variation in leaves and stem bases during AR induction of microcuttings to elucidate the molecular mechanisms involved in AR formation. In addition, we quantified expressions of candidate genes associated with recalcitrance. We delimited the ontogenic phases of root formation using histological techniques and Scarecrow and Short-Root expression quantification for RNA sequencing sample collection. We quantified the gene expressions associated with root meristem formation, auxin biosynthesis, perception, signaling, conjugation, and cytokinin signaling in shoots harvested from 2- to 36-month-old plants. After IBA treatment, 702 transcripts changed their expressions. Several were involved in hormone homeostasis and the signaling pathways that determine cell dedifferentiation, leading to root meristem formation. In part, the age-related decline in the rooting capacity is attributable to the increase in the ARR1 gene expression, which negatively affects auxin homeostasis. The analysis of the transcriptomic variation in the leaves and rooting zones provided profuse information: (1) To elucidate the auxin metabolism; (2) to understand the hormonal and signaling processes involved; (3) to collect data associated with their recalcitrance.

Anther structure and pollen development in species of Rubiaceae and anatomical evidence of pathway to morphological dioecy.

we conducted anatomical analysis of anthers with the aim to establish the differences in the development pattern of microsporophytes and microgametophytes between perfect and imperfect flowers in the tribe Gardenieae (Rubiaceae). The species studied were: Tocoyena formosa (monoecious with perfect flowers), Cordiera concolor, Genipa americana, Randia calycina, and Randia heteromera (dioecious with imperfect flowers). Flowers in successive stages of development were collected and fixed. The material was processed and examined using light microscopy and scanning electron microscopy. The present study revealed the stage when pollen is arrested in the functionally pistillate flowers of the dioecious taxa. Based on these observations an evolutionary sequence of changes towards the reduction of non-functional anthers in Rubiaceae is proposed. In addition, we describe and discuss characters that might be of importance in future phylogenetic studies in Rubiaceae (e.g., pollen morphology and its dispersal unit, the presence of orbicules, and a new type of placentoid).

Assessment of in vitro bioaccessibility of carotenoids and phenolic compounds in a model milk-mandarine beverage.

Mandarine juice is one of the richest sources of ß-cryptoxanthin and flavonoids, which have been positively associated with bone mineral density. Carotenoids are lipophilic isoprenoid compounds with a complex absorption process that can be affected by different factors. In this study, we have evaluated the effect of the food matrix on the in vitro bioaccessibility of carotenoids and phenolic compounds in a model milk-mandarine beverage (MMB). MMBs were formulated with mandarine juice and different dairy products to achieve three fat levels (0.2%, 1.7% and 3.2%) and three calcium levels (120, 310 and 500 mg Ca2+ per 100 ml). The bioaccessibility was evaluated using a harmonised in vitro digestion method. The results showed that the content of milk fat increased the bioaccessibility in vitro of phenolic compounds (p < 0.05), while a moderate fat level (1.7%) resulted in the highest bioaccessibility for bioactive carotenoids. On the other hand, calcium fortification at the highest level (500 mg Ca2+ per 100 mL) decreased the bioaccessibility of bioactive carotenoids from 76% to 43% (66% for the major ß-cryptoxanthin) compared to the lower calcium fortification level (120 mg Ca2+ per 100 mL). The bioaccessibility of hesperidin, the main flavanone in mandarine juice, was significantly (p < 0.05) reduced in the MMB with the highest calcium level. The bioaccessibility of carotenoids and phenolic compounds is affected by fat and calcium levels. When formulating functional beverages, the impact of the formulation should be carefully considered to optimize the bioaccessibility of the bioactive compounds.

Anatomy and development of the edible fruits of Cordiera concolor (Rubiaceae).

A comprehensive study on the fruit anatomy and development of Cordiera concolor was carried out to establish the origin of the gelatinous tissue surrounding the seeds at maturity. Cordiera currently belongs to tribe Cordiereae, forming part of the species-rich lineage called Gardenieae complex. Most genera of Gardenieae complex has many-seeded fleshy fruits, with seeds usually imbedded in a pulp, which historically was considered of a placental nature. For the histological analyses, fruits at different stages of development were fixed in formalin-acetic acid-alcohol and examined with light microscopy. The endocarp has no woody consistency, it is what classifies a fruit as berry. The pericarp is differentiated into three histological zones: 1) the exocarp, formed of the epidermis and the sub-epidermal tannin cells, 2) the mesocarp, consisting of parenchyma with tannins and druses, and 3) the endocarp, derived from the internal epidermis of the ovary. The placental tissue has little development during the formation of the pericarp. We concluded that the gelatinous tissue surrounding the seeds in the ripe fruit is formed of the mesocarp and endocarp. The present results disagree with the widely accepted conception of the placental origin of the gelatinous pulp surrounding the seeds in Gardenieae Complex species.

Opportunities for the conservation of migratory birds to benefit threatened resident vertebrates in the Neotropics.

Neotropical countries receive financing and effort from temperate nations to aid the conservation of migratory species that move between temperate and tropical regions. If allocated strategically, these resources could simultaneously contribute to other conservation initiatives. In this study, we use novel distribution maps to show how those resources could aid planning for the recovery of threatened resident vertebrates.Using eBird-based relative abundance estimates, we first identified areas with high richness of Neotropical migrant landbirds of conservation concern (23 species) during the stationary non-breeding period. Within these areas, we then identified threatened species richness, projected forest loss and conducted a prioritization for 1,261 red-listed vertebrates using Terrestrial Area-of-Habitat maps.Richness for migrants was greatest along a corridor from the Yucatan peninsula south to the northern Andes but also included south-west Mexico and Hispaniola. Protected areas account for 22% of this region while 21% is at risk of forest loss. Within this focal region for migrants, all four vertebrate groups showed hotspots of threatened species richness along the west and east Andean slopes. Taxa-specific hotspots included montane areas of southern Mexico and central Guatemala (amphibians/reptiles) and the entire east slope of the Colombian East Andes (mammals).Our prioritization highlighted several areas of importance for conservation due to high threatened species richness and projected forest loss including (a) the Pacific dry forests of south-west Mexico, (b) montane regions of northern Central America and (c) the west Andean slope of Colombia and Ecuador. At a landscape scale in southern Colombia, we show how conservation efforts for six Neotropical migrants could benefit 56 threatened residents that share a similar elevational range. Synthesis and applications. Funding and effort for migratory bird conservation also has potential to benefit threatened resident vertebrates in the Neotropics. Our study highlights how novel, high-resolution information on species distributions and risk of forest loss can be integrated to identify priority areas for the two groups at regional and landscape scales. The approach and data can be further modified for more specific goals, such as within-country initiatives.

Los países neotropicales reciben financiamiento y recursos esfuerzos de países templados para ayudar a la conservación de las aves migratorias que se mueven entre estas dos regiones. Si se asignan estratégicamente, estos recursos podrían beneficiar simultáneamente a otras iniciativas de conservación. En esta investigación, usamos novedosos mapas de distribución para mostrar cómo esos recursos podrían ayudar a planificar la conservación de especies residentes amenazadas.Utilizando estimaciones de abundancia de eBird, delineamos la Región Focal con la mayor riqueza de aves migratorias neotropicales de interés para la conservación durante el periodo invernal (23 especies). Dentro de esta región, determinamos la riqueza de especies residentes amenazadas, la proyección de pérdida de bosque, y realizamos una priorización para 1261 especies de vertebrados incluidos en la lista roja de la IUCN utilizando mapas del área de hábitat terrestre.En la Región Focal, la riqueza de aves migratorias fue mayor a lo largo de un corredor desde el sur de la península de Yucatán hasta el norte de los Andes, y en el suroeste de México y la isla La Española. Las áreas protegidas representan 22% de esta región mientras que el 21% está en riesgo de pérdida de bosque. Dentro de la Región Focal para las aves migratorias, todos los vertebrados residentes mostraron puntos de mayor riqueza de especies amenazadas en los Andes occidentales y orientales. Las regiones con mayor riqueza para taxones específicos incluyeron las montañas del sur de México y del centro de Guatemala (anfibios y reptiles) y la vertiente oriental de la cordillera oriental de Colombia (mamíferos).La priorización destacó varias áreas de importancia para la conservación debido a la alta riqueza de especies amenazadas y a la pérdida de bosque proyectada incluyendo 1) los bosques secos del Pacífico del suroeste de México, 2) las regiones montañosas del norte de Centroamérica y 3) la vertiente occidental de los Andes Occidental de Colombia y Ecuador. A escala del paisaje en el sur de Colombia, mostramos cómo los esfuerzos para la conservación de 6 aves migratorias podrían beneficiar a 56 especies residentes amenazadas que comparten un rango altitudinal similar. Síntesis y aplicaciones. La financiación y esfuerzos para la conservación de las aves migratorias tienen el potencial a beneficiar a los vertebrados residentes amenazados en el Neotrópico. Nuestro estudio resalta como se puede integrar información novedosa y de alta resolución acerca de la distribución de especies y el riesgo de pérdida de bosques para identificar áreas prioritarias para los dos grupos a escala regional y paisajística. El enfoque y los datos se pueden modificar para objetivos más específicos, como por ejemplo iniciativas dentro de cada país.

Extinction, coextinction and colonization dynamics in plant-hummingbird networks under climate change.

Climate-driven range shifts may cause local extinctions, while the accompanying loss of biotic interactions may trigger secondary coextinctions. At the same time, climate change may facilitate colonizations from regional source pools, balancing out local species loss. At present, how these extinction-coextinction-colonization dynamics affect biological communities under climate change is poorly understood. Using 84 communities of interacting plants and hummingbirds, we simulated patterns in climate-driven extinctions, coextinctions and colonizations under future climate change scenarios. Our simulations showed clear geographic discrepancies in the communities' vulnerability to climate change. Andean communities were the least affected by future climate change, as they experienced few climate-driven extinctions and coextinctions while having the highest colonization potential. In North America and lowland South America, communities had many climate-driven extinctions and few colonization events. Meanwhile, the pattern of coextinction was highly dependent on the configuration of networks formed by interacting hummingbirds and plants. Notably, North American communities experienced proportionally fewer coextinctions than other regions because climate-driven extinctions here primarily affected species with peripheral network roles. Moreover, coextinctions generally decreased in communities where species have few overlapping interactions, that is, communities with more complementary specialized and modular networks. Together, these results highlight that we should not expect colonizations to adequately balance out local extinctions in the most vulnerable ecoregions.

Embryology of some flowers of the Gardenieae complex (Rubiaceae).

Different breeding systems occur in the Gardenieae complex (Rubiaceae), from homoecy to dioecy which is present in two tribes, Gardenieae and Cordiereae. As part of a broad project focused on the reproductive anatomy of the species of these two tribes, we described the structural and functional differences of the gynoecium in the different floral morphs and determined the degree of gynoecium development in the staminate flowers. We conducted a comparative anatomical study focused on the gynoecium of one homoecious species (Tocoyena formosa, with perfect flowers) and three dioecious species (Genipa americana, Randia calycina, and Randia heteromera) of Gardenieae and one dioecious species (Cordiera concolor) of Cordiereae. The dioecious species have flowers that are morphologically perfect and functionally unisexual. Flowers in successive stages of development were collected, photographed, and fixed in formalin-acetic acid-alcohol. The material was examined using light microscopy and scanning electron microscopy. The anatomy of the ovary, style, and stigma was analyzed, and megasporogenesis and megagametogenesis were studied. The results achieved in this study, together with previously obtained data of the androecium, show that dioecy originated from homoecy in these species, since the unisexual flowers conserve some characteristics of the perfect flowers. In addition, a new type of ovule for the Rubiaceae family is described.

A field study reveals links between hyperaccumulating Sedum plants-associated bacterial communities and Cd/Zn uptake and translocation.

Hyperaccumulating ecotypes of Sedum plants are promising Cd/Zn phytoextractors, with potential for leveraging its rhizospheric or endophytic microbiomes to improve phytoremediation efficiency. However, research of bacteria associated with Sedum at field scale is still lacking. Here, we presented a detailed investigation of the bacterial microbiome of hyperaccumulating Sedum ecotypes (S. alfredii and S. plumbizincicola) and a non-hyperaccumulating S. alfredii ecotype, which grow at different soil environments. Moreover, we evaluated the heavy metal uptake and translocation potential of Sedum plants at different locations. The results showed that both HE ecotypes, contrary to the NHE, were efficient for phytoremediation in mine areas and farmlands. For NHE plants, rhizosphere co-occurrence networks were more complex than the networks of other compartments, while networks of HE plants were more complex in bulk soil and roots. The proportion of positive correlations within co-occurrence networks was higher for the HE plants, suggesting a greater potential for mutualistic interactions. Plant compartment and location predominantly shaped the microbiome assembly, and Proteobacteria, Actinobacteria and Acidobacteria dominated the bacterial communities of Sedum plants. Keystone taxa related to Zn hyperaccumulation are similar to those related to Cd hyperaccumulation, and nine bacterial genera had significantly positive correlation with Cd/Zn hyperaccumulation. Taxa, linked to phytoremediation in both mine and farmland (i.e. Actinospica and Streptomyces from Actinobacteria), could be targets for further investigation of their ability to promote metal phytoremediation of Sedum species.

Amaranth Seeds and Sprouts as Functional Ingredients for the Development of Dietary Fiber, Betalains, and Polyphenol-Enriched Minced Tilapia Meat Gels.

There is an increasing interest in the development of meat processed products enriched with antioxidant dietary fiber to augment the consumption of these health beneficial compounds. This study aimed to evaluate the nutritional, nutraceutical, and antioxidant potential, as well as the physicochemical properties of minced tilapia fillets (meat) gels with added amaranth seed or sprout flours (0%, 2%, 4%, 8%, and 10% w/w). Dietary fiber content was significantly increased with the addition of amaranth seed (1.25-1.75-fold) and sprout flours (1.99-3.21-fold). Tilapia gels with added 10% amaranth seed flour showed a high content of extractable dihydroxybenzoic acid and cinnamic acid, whereas the addition of 10% amaranth sprout flour provided a high and wide variety of bioactive compounds, mainly amaranthine and bound ferulic acid. The addition of amaranth seed and sprout flours increased hardness (1.01-1.73-fold) without affecting springiness, decreased luminosity (1.05-1.15-fold), and increased redness and yellowness. Therefore, amaranth seed and sprout flours could be used as functional ingredients for the development of fish products rich in bioactive compounds.