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Cryptic species represent a substantial fraction of the diversity of Drosophilidae, hampering studies on species ecologies and their evolution. Anthophilous species within the Drosophila lutzii group encompass some of the most widely distributed Neotropical lineages. Nevertheless, their ranges, ecologies, divergence times, and phylogenetic relationships are largely unknown. In this study, we analyzed the cryptic diversity of the lutzii species complex occurring in Southern Brazil and shed light on the ecological and evolutionary processes underlying their current patterns of coexistence. We used an integrative approach, evaluating molecular, ecological, and morphological traits under an evolutionary ecology framework. We documented the unexpected occurrence of D. alei in Southern Brazil, whose range was only known for the Andean region. Our phylogenetic analysis indicated that despite morphological similarities, D. alei is more closely related to D. denieri than to D. lutzii , and that divergence among these three species dates back to the Neogene (7.3 Mya). Niche modeling suggests that D. denieri and D. lutzii populations expanded their ranges and were established in Southern Brazil during the Quaternary (150 kya), being affected by similar paleoclimatic events. On the other hand, D. alei shows distinct abiotic requirements than D. denieri and D. lutzii , and environmental distribution models suggested a significant reduction in its suitable areas during the Quaternary, especially in Southern Brazil. This suggests that the current sympatry observed in this region likely reflects a secondary contact between the three species resulting from niche divergence processes. Altogether, these results advance the understanding of the distribution and phylogenetic relationships of Neotropical anthophilous Drosophila , revealing the interplay between ecological and historical factors in their speciation. [ABSTRACT FROM AUTHOR]

Saponins are amphipathic glycosides with detergent properties present in vegetables. These compounds, when ingested, can cause difficulties in absorbing nutrients from food and even induce inflammatory processes in the intestine. There is already some evidence that saponins can be degraded by β-glucosidases of the GH3 family. In the present study, we evaluated, through computational tools, the possibility of a β-glucosidase (AMBGL17) obtained from a metagenomic analysis of the Amazonian soil, to catalytically interact with a saponin present in soybean. For this, the amino acid sequence of AMBGL17 was used in a phylogenetic analysis to estimate its origin and to determine its three-dimensional structure. The 3D structure of the enzyme was used in a molecular docking analysis to evaluate its interaction with soy saponin as a ligand. The results of the phylogenetic analysis showed that AMBGL17 comes from a microorganism of the phylum Chloroflexi, probably related to species of the order Aggregatinales. Molecular docking showed that soybean saponin can interact with the catalytic site of AMBGL17, with the amino acid GLY345 being important in this catalytic interaction, especially with a β-1,2 glycosidic bond present in the carbohydrate portion of saponin. In conclusion, AMBGL17 is an enzyme with interesting biotechnological potential in terms of mitigating the anti-nutritional and pro-inflammatory effects of saponins present in vegetables used for human and animal food.   Insight box Saponins are amphipathic glycosides present in plant matter that can cause difficulties in the absorption of nutrients from food and even inflammatory processes in the intestine. There is evidence that β-glycosidases can degrade saponins. In the present study, an amino acid sequence of a β-glucosidase obtained from an Amazonian soil metagenomic library had its three-dimensional structure computationally modeled. The 3D model was used to test, through molecular docking, its ability to degrade a soy saponin. The results obtained show that the β-glucosidase studied here has the possibility of degrading soy saponin, showing an interesting biotechnological potential to mitigate the anti-nutritional and pro-inflammatory effects of saponins present in vegetables used in human and animal food. [ABSTRACT FROM AUTHOR]

Growth hormone (GH) transgenesis presents a high potential application in aquaculture. However, excess GH may have serious consequences due to pleiotropic actions. In order to study these effects in zebrafish ( Danio rerio), two transgenic lines were developed. The first expresses GH ubiquitously and constitutively (F0104 line), while the second expresses the GH receptor in a muscle-specific manner (Myo-GHR line). Results from the F0104 line showed accelerated growth but increased reproductive difficulties, while Myo-GHR did not show the expected increase in muscle mass. Since the two lines appeared to display complementary characteristics, a double transgenic (GH/GHR) was created via crossing between them. This double transgenic displayed accelerated growth, however reproductive parameters remained uncertain. The objective of the present study was to determine the reproductive capacity of males of this new line, by evaluating sperm parameters, expression of spermatogenesis-related genes, and reproductive tests. Double transgenics showed a strong recovery in almost all sperm parameters analyzed when compared to the F0104 line. Gene expression analyses revealed that Anti-Müllerian Hormone gene ( amh) appeared to be primarily responsible for this recovery. Reproductive tests showed that double transgenic males did not differ from non-transgenics. It is possible that GHR excess in the muscle tissues of double transgenics may have contributed to lower circulating GH levels and thus reduced the negative effects of this hormone with respect to reproduction. Therefore, it is clear that GH-transgenesis technology should take into account the need to obtain adequate levels of circulating hormone in order to achieve maximum growth with minimal negative side effects. [ABSTRACT FROM AUTHOR]

We provide ultrastructural and cytological evidence that the tentacles of the sea anemone Bunodosoma cangicum does not contain cytotoxic venom. However, we show that the stimulated secretion of an apparent mixture of biomolecules containing polypeptides from the columnar vesicles of Bunodosoma cangicum is apparently a potent inducer of apoptosis in the zebrafish cell line, ZF-L. Microscopic fluorescence, cell morphology and flow cytometric assays confirm the apoptotic activity. Crude vesicle venom was partially purified by size exclusion chromatography. PAGE analysis shows that this venom contains low weight polypeptides but no measurable protein. The apoptotic activity is heat labile, and the observed peptides concurrent with this activity have a molecular weight of approximately 2000 Da. This manuscript is the first report of biologically active molecules and peptides associated with columnar vesicles of anemones, and the first to confirm that the tentacles of B. cangicum do not contain cytotoxic venom, and express spirocytes exclusively. [ABSTRACT FROM AUTHOR]