A new single nucleotide polymorphism in the rabbit (Oryctolagus cuniculus) myostatin (MSTN) gene is associated with carcass composition traits

This study aimed at the identification of genetic variations in the myostatin (MSTN) gene and testing their effects on carcass quality traits. We comparatively sequenced Giant Grey (GG) and New Zealand White (NZW) rabbits that were founders of a cross‐bred population. Alignment of our sequence data with the GenBank sequence of the rabbit MSTN gene (Ensembl Gene ID ENSOCUG00000012663) identified three single nucleotide polymorphisms (SNPs). The two novel SNPs (c.?125T>C, c.373+234G>A) and one known SNP (c.747+34C>T) were subsequently analysed for linkage with carcass composition traits in 363 F₂ animals of the cross GG × NZW. Significant linkage was found between c.373+234G>A and nine carcass composition traits (P < 0.05). No significant effects were found for c.?125T>C and c.747+34C>T. Because the linked SNP is located in intron 1 and no genetic variation was found in the coding region, further investigations are necessary to understand the functional effect of the c.373+234G>A variant on the variability of the traits.     

Reproduction of the rare monocarpic species Saxifraga mutata L.

The aim of the study is to investigate the impact of reproduction and genetic variation on the persistence of populations of the prealpine, monocarpic Saxifraga mutata L. The species grows on erosion slopes or rocks, and its local populations are often small and isolated. Crossing experiments resulted in better seed-set than selfing, but both yielded viable seeds. Agamospermy did not occur. In an early-successional species like S. mutata , successful selfing is important in the colonization of new habitats. Flowers of S. mutata were visited by Syrphidae and unspecialized Hymenoptera. A germination rate of 40% was reached in cultivation after 20 weeks but germination continued until the end of the experiment after 92 weeks. Seeds stored dry for 30 months at room temperature mostly lost their germinability. In natural habitats, seedlings were found almost throughout the year with a peak in spring. Suitable safe sites were small patches of open soil, bare marl on erosion slopes, and rock crevices. AU individuals investigated were diploid with 2n = 26. Allozyme electrophoresis showed a lack of segregation within the populations. Intra- and interpopulation genetic variation was low. These results were in partial disagreement with theoretical expectations in a mixed mating species. It is concluded that demographic rather than genetic processes are the main cause of extinction of populations of S. mutata , at least in the short-term.     

Within- and among-population variation in oviposition preference for urea-supplemented food inDrosophila melanogaster

Oviposition preference for ureasupplemented food was assayed by simultaneous choice trials on five pairs of closely related laboratory populations of Drosophila melanogaster.Each pair of populations had been derived from a separate ancestral population about 85 generations prior to this study. One population in each pair had been subjected to selection for larval tolerance to the toxic effects of urea; the other population served as a control. Considerable variation in oviposition preference was seen both within and among populations, with four of the ten populations showing a significant mean preference for ureasupplemented food. The degree of specificity shown by individual females was surprisingly high, leading to a bimodal distribution of oviposition preference in some populations. Overall, selection for larval tolerance to urea did not significantly affect oviposition preference. However, the data indicated that pairwise comparisons between randomly selected populations from the two larval selection regimes would lead to a range of possible outcomes, suggesting, in several cases, that selection for larval urea tolerance had led to significant differentiation of adult oviposition preference for urea in one or the other direction. The results, therefore, highlight the importance of population level replication and caution against the practice, common in ecological studies, of assaying oviposition preference in two populations that utilize different hosts in nature, and then drawing broad evolutionary inferences from the results.     

New insights into the population biology of endoparasitic Rafflesiaceae

Parasitic plants demonstrate a diversity of growth strategies, life histories, and developmental and physiological characteristics. Most research to date has focused on a narrow range of parasitic taxa, particularly in the Orobanchaceae, while the other independent origins of parasitism have largely gone unstudied. One type of parasite that has received relatively little attention are the endophytic parasites, which have a fascinating growth strategy where the parasite is embedded within the host tissue, with the flower the only externally visibly plant part. Endophytic growth makes it challenging to understand basic aspects of species biology, such as the size of a given parasite, the number of parasites per host, and the genetic diversity of populations. Recent studies by Barkman et al. (2017) and Pelser et al. (2017) have used microsatellite genotyping to investigate the population biology of endoparasitic Rafflesiaceae species in Asia. They show the potential for extensive parasite spread within a host vine and the strong partitioning of genetic diversity by host. These species are also shown to have an outcrossing mating system. However, these studies suggest different reproductive strategies, one supporting monoecy and one suggesting dioecy. Overall, these studies partly “lift the lid” on the cryptic biology of Rafflesia and the Rafflesiaceae and open the door for future comparative studies between endophytic and free-living parasitic plants.     

A biophysical and computational study unraveling the molecular interaction mechanism of a new Janus kinase inhibitor Tofacitinib with bovine serum albumin

The interaction of a recently certified kinase inhibitor Tofacitinib (TFB) with bovine serum albumin (BSA) has been studied, by spectroscopic and molecular docking studies. Spectrofluorimetric measurements at 3 different temperatures (288, 298, and 310 K) showed that TFB quench the intrinsic fluorescence of BSA upon forming a nonfluorescent complex. The intrinsic fluorescence data showed that TFB binds to BSA with binding constant (K _b) of approximately 10⁴M⁻¹, affirming a significant affinity of TFB with BSA. The decrease in Stern‐Volmer quenching constant with increasing temperature exhibited the static mechanism of quenching. Negative value of ΔG (−6.94 ± 0.32 kcal·mol⁻¹), ΔH (−7.87 ± 0.52 kcal·mol⁻¹), and ΔS (−3.14 ± 0.42 cal·mol⁻¹·K⁻¹) at all 3 temperatures declared the reaction between BSA and TFB to be spontaneous and exothermic. Far‐UV circular dichroism spectroscopy results demonstrated an increase in helical content of BSA in the presence of TFB. Moreover, dynamic light scattering measurements showed that TFB resulted into a decrease in the hydrodynamic radii (from 3.6 ± 0.053 to 2.9 ± 0.02 nm) of BSA. Molecular docking studies confirmed that TFB binds near site II on BSA, hydrogen bonding, and hydrophobic interaction were involved in the BSA‐TFB complex formation. The present study characterizing the BSA‐TFB interaction could be significant towards gaining an insight into the drug pharmacokinetics and pharmacodynamics and also in the direction of rational drug designing with better competence, against emerging immune‐mediated diseases, ie, alopecia and rheumatoid arthritis.     

Intrageneric amplification of horse microsatellite markers with emphasis on the Przewalski's horse (E. pmewalskii)

Primer sequences flanking 13 microsatellite loci isolated from the domestic horse (E. caballus) were successfully used to amplify homologous loci in the Przewalski's horse (E. przewalskii). The results demonstrate that the level of polymorphism at all 13 loci in the Przewalski's horse was comparable to that in the domestic horse and the overall exclusion probability in the Przewalski's horse was calculated to be 0.9994. The results suggest that it should be possible to use E. caballus-derived microsatellite markers to provide parentage verification and additional valuable information to the captive management of E. przewalskii. The ability to amplify corresponding loci in the remaining five species of the genus was also confirmed, illustrating the general application of markers isolated from the domestic horse to the evaluation of polymorphism in the other six species of the genus.     

Lake sturgeon management in the Menominee River, a Wisconsin-Michigan boundary water

The Menominee River, a boundary water between northeastern Wisconsin and the upper peninsula of Michigan, contains a sport fishery for lake sturgeon, Acipenser fulvescens, which is jointly managed by both states. Previous studies indicated that overfishing of this sturgeon population was occurring, and this investigation examined the impact of new angling regulations. The sturgeon population is fragmented into sections by hydroelectric dams. Stocks from the three main sections of the river were compared before and after implementation of the new angling regulations. Records of the legal harvest of lake sturgeon from each river section were obtained through a registration system, which has been in effect since 1983, and estimates of exploitation were derived from these data. Overfishing of lake sturgeon stocks in two of the three sections of the Menominee River is still occurring. Management recommendations are made which would allow for a continued fishery by providing further protection to the stocks.     

Factors influencing seasonal and monthly changes in the group size of chital or axis deer in southern India

Chital or axis deer (Axis axis) form fluid groups that change in size temporally and in relation to habitat. Predictions of hypotheses relating animal density, rainfall, habitat structure, and breeding seasonality, to changes in chital group size were assessed simultaneously using multiple regression models of monthly data collected over a 2 yr period in Guindy National Park, in southern India. Over 2,700 detections of chital groups were made during four seasons in three habitats (forest, scrubland and grassland). In scrubland and grassland, chital group size was positively related to animal density, which increased with rainfall. This suggests that in these habitats, chital density increases in relation to food availability, and group sizes increase due to higher encounter rate and fusion of groups. The density of chital in forest was inversely related to rainfall, but positively to the number of fruiting tree species and availability of fallen litter, their forage in this habitat. There was little change in mean group size in the forest, although chital density more than doubled during the dry season and summer. Dispersion of food items or the closed nature of the forest may preclude formation of larger groups. At low densities, group sizes in all three habitats were similar. Group sizes increased with chital density in scrubland and grassland, but more rapidly in the latter—leading to a positive relationship between openness and mean group size at higher densities. It is not clear, however, that this relationship is solely because of the influence of habitat structure. The rutting index (monthly percentage of adult males in hard antler) was positively related to mean group size in forest and scrubland, probably reflecting the increase in group size due to solitary males joining with females during the rut. The fission-fusion system of group formation in chital is thus interactively influenced by several factors. Aspects that need further study, such as interannual variability, are highlighted.     

Diel vertical migration ofEudiaptomus gracilis during a short summer period

Several aspects of a diel vertical migration (DVM) of adultEudiaptomus gracilis in Lake Maarsseveen (The Netherlands) are described. The period of DVM lasted from the end of May until the middle of August. On May 21, 1989, the population was found divided into a deep dwelling part and a part in the upper five meter. Large shoals of juvenile perch were observed in the open water for the first time. On June 7, the whole population was down below 10 m and concentrated in a zone of high chlorphyll-a concentrations. One week later, a regular DVM was performed. The amplitude of this migration gradually decreased towards the end of the migration period. The ascent in the evening and the descent in the morning took place after sunset and before sunrise, respectively. The movements coincided with high relative changes in light intensity. Population size increased rapidly during the period of DVM but decreased again before the end of this period.     

Genome-wide data from medieval German Jews show that the Ashkenazi founder event pre-dated the 14th century

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