Transferability and characterization of microsatellite markers from Byrsonima cydoniifolia A. Juss. (MALPIGHIACEAE) in seven related taxa from Cerrado biome reveal genetic relationships

Byrsonima Rich. is one of the largest genera of the Malpighiaceae family with 97 species occurrence in Brazil and multiple potentialities, including pharmaceutical and food industries. In this study, 17 microsatellite markers characterized in Byrsonima cydoniifolia were tested for seven related taxa, all species are native to Brazil and four are endemic. Genomic DNA was extracted from leaves tissues and 17 microsatellite markers were used to cross-amplification of microsatellite regions. Polymorphism and genetic diversity were evaluated for B. intermedia, B. verbascifolia, B. laxiflora, B. subterranea, B. umbellata, B. linearifolia. from 16 individuals and for B. viminifolia from 14 individuals. Transferred microsatellite markers panels ranged from 11 (64.8%) in B. viminifolia to 6 (35.2%) in B. umbellata. The total number of alleles per locus ranged from 5 (B. linearifolia) to 8 (B. subterranea) alleles. B. umbellata showed lower values of observed and expected heterozygosity (H_O?=?0.312; H_E?=?0.436) and B. subterranea presented the highest values (H_O?=?0.687; H_E?=?0.778). A greater number of microsatellite markers should be developed for B. umbellata. The microsatellite marker panels transferred to the species B. intermedia, B. verbascifolia, B. laxiflora, B. subterranea, B. viminifolia and B. linearifolia are very informative, with a high combined probability of exclusion of paternity (Q?≥?0.976) and the low combined probability of identity (I?≤?9.91?×?10^–6), potentially suitable for future genetic-population studies, supporting strategies for maintaining the genetic diversity and for exploration of Byrsonima species as genetic resources.

     

Increased Retinal Ganglion Cell Survival by Exogenous IL-2 Depends on IL-10, Dopamine D1 Receptors,and Classical IL-2/IL-2R Signaling Pathways

Neurochemical Research - Interleukin-2 (IL-2) is a classical pro-inflammatory cytokine known to display neuroprotective roles in the central nervous system including the retina. In the present...     

Functional unit influence on building life cycle assessment

Purpose

The building sector is one of the most relevant sectors in terms of environmental impact. Different functional units (FUs) can be used in life cycle assessment (LCA) studies for a variety of purposes. This paper aimed to present different FUs used in the LCA of buildings and evaluate the influence of FU choice and setting in comparative studies.

Methods

As an example, we compared the “cradle to grave” environmental performance of four typical Brazilian residential buildings with different construction typologies, i.e., multi-dwelling and single dwelling, each with high and basic standards. We chose three types of FU for comparison: a dwelling with defined lifetime and occupancy parameters, an area of 1 m² of dwelling over a year period, and the accommodation of an occupant person of the dwelling over a day.

Results and discussion

The FU choice was found to bias the results considerably. As expected, the largest global warming indicator (GWi) values per dwelling unit and occupant were identified for the high standard dwellings. However, when measured per square meter, lower standard dwellings presented the largest GWi values. This was caused by the greater concentration of people per square meter in smaller area dwellings, resulting in larger water and energy consumption per square meter. The sensitivity analysis of FU variables such as lifetime and occupancy showed the GWi contribution of the infrastructure more relevant compared with the operation in high and basic standard dwellings. The definition of lifetime and occupancy parameters is key to avoid bias and to reduce uncertainty of the results when performing a comparison of dwelling environmental performances.

Conclusions

This paper highlights the need for adequate choice and setting of FU to support intended decision-making in LCA studies of the building sector. The use of at least two FUs presented a broader picture of building performance, helping to guide effective environmental optimization efforts from different approaches and levels of analysis. Information regarding space, time, and service dimensions should be either included in the FU setting or provided in the building LCA study to allow adjustment of the results for subsequent comparison.

     

Membrane interactions of the anuran antimicrobial peptide HSP1-NH2: Different aspects of the association to anionic and zwitterionic biomimetic systems

Studies have suggested that antimicrobial peptides act by different mechanisms, such as micellisation, self-assembly of nanostructures and pore formation on the membrane surface. This work presents an extensive investigation of the membrane interactions of the 14 amino-acid antimicrobial peptide hylaseptin P1-NH₂ (HSP1-NH₂), derived from the tree-frog Hyla punctata, which has stronger antifungal than antibacterial potential. Biophysical and structural analyses were performed and the correlated results were used to describe in detail the interactions of HSP1-NH₂ with zwitterionic and anionic detergent micelles and phospholipid vesicles. HSP1-NH₂ presents similar well-defined helical conformations in both zwitterionic and anionic micelles, although NMR spectroscopy revealed important structural differences in the peptide N-terminus. ²H exchange experiments of HSP1-NH₂ indicated the insertion of the most N-terminal residues (1–3) in the DPC-d₃₈ micelles. A higher enthalpic contribution was verified for the interaction of the peptide with anionic vesicles in comparison with zwitterionic vesicles. The pore formation ability of HSP1-NH₂ (examined by dye release assays) and its effect on the size and surface charge as well as on the lipid acyl chain ordering (evaluated by Fourier-transform infrared spectroscopy) of anionic phospholipid vesicles showed membrane disruption even at low peptide-to-phospholipid ratios, and the effect increases proportionately to the peptide concentration. On the other hand, these biophysical investigations showed that a critical peptide-to-phospholipid ratio around 0.6 is essential for promoting disruption of zwitterionic membranes. In conclusion, this study demonstrates that the binding process of the antimicrobial HSP1-NH₂ peptide depends on the membrane composition and peptide concentration.     

Endocytosis of the non-catalytic ADAM23: Recycling and long half-life properties

A Disintegrin And Metalloprotease 23 (ADAM23) is a member of the ADAMs family of transmembrane proteins, mostly expressed in nervous system, and involved in traffic and stabilization of Kv1-potassium channels, synaptic transmission, neurite outgrowth, neuronal morphology and cell adhesion. Also, ADAM23 has been linked to human pathological conditions, such as epilepsy, cancer metastasis and cardiomyopathy. ADAM23 functionality depends on the molecule presence at the cell surface and along the secretory pathway, as expected for a cell surface receptor. Because endocytosis is an important functional regulatory mechanism of plasma membrane receptors and no information is available about the traffic or turnover of non-catalytic ADAMs, we investigated ADAM23 internalization, recycling and half-life properties. Here, we show that ADAM23 undergoes constitutive internalization from the plasma membrane, a process that depends on lipid raft integrity, and is redistributed to intracellular vesicles, especially early and recycling endosomes. Furthermore, we observed that ADAM23 is recycled from intracellular compartments back to the plasma membrane and thus has longer half-life and higher cell surface stability compared with other ADAMs. Our findings suggest that regulation of ADAM23 endocytosis/stability could be exploited therapeutically in diseases in which ADAM23 is directly involved, such as epilepsy, cancer progression and cardiac hypertrophy.     

Replication and partitioning of the apicoplast genome of Toxoplasma gondii is linked to the cell cycle and requires DNA polymerase and gyrase

Apicomplexans are the causative agents of numerous important infectious diseases including malaria and toxoplasmosis. Most of them harbour a chloroplast-like organelle called the apicoplast that is essential for the parasites’ metabolism and survival. While most apicoplast proteins are nuclear encoded, the organelle also maintains its own genome, a 35 kb circle. In this study we used Toxoplasma gondii to identify and characterise essential proteins involved in apicoplast genome replication and to understand how apicoplast genome segregation unfolds over time. We demonstrated that the DNA replication enzymes Prex, DNA gyrase and DNA single stranded binding protein localise to the apicoplast. We show in knockdown experiments that apicoplast DNA Gyrase A and B, and Prex are required for apicoplast genome replication and growth of the parasite. Analysis of apicoplast genome replication by structured illumination microscopy in T. gondii tachyzoites showed that apicoplast nucleoid division and segregation initiate at the beginning of S phase and conclude during mitosis. Thus, the replication and division of the apicoplast nucleoid is highly coordinated with nuclear genome replication and mitosis. Our observations highlight essential components of apicoplast genome maintenance and shed light on the timing of this process in the context of the overall parasite cell cycle.     

Differences between species in seed bank and vegetation helps to hold functional diversity in a floodable Neotropical savanna

种子库和植被物种之间的差异有助于保持新热带稀树草原的功能多样性 本研究的目的是量化种子库和建立的植被对物种组成、功能组成和多样性的贡献,并讨论这些差异对冲积平原植物群落更新和稳定性的影响。我们在巴西潘塔纳尔湿地的一个周期性洪水泛滥的稀树大草原上,在旱季和雨季对分布在5个地点的25个地块(10 m × 1 m)的1.5 m高度的地面覆盖植被和种子库进行了采样。采用出苗法对土壤种子库进行了评价。研究结果表明,种子库物种具有赋予群落更新的特征,而植被则具有稳定性特征。种子库的功能丰富度高于植被,而功能均匀度则低于植被。由于种子库和植被的植物特征不同,使得具有不同功能稳定性和更新特性的物种得以共存,这将有助于维持植物的功能多样性。这可能会让植物种群在应对干旱、火灾和洪水等不同的环境选择时更具有弹性。