Nucleosomes affect local transformation efficiency

Genetic transformation is a natural process during which foreign DNA enters a cell and integrates into the genome. Apart from its relevance for horizontal gene transfer in nature, transformation is also the cornerstone of today's recombinant gene technology. Despite its importance, relatively little is known about the factors that determine transformation efficiency. We hypothesize that differences in DNA accessibility associated with nucleosome positioning may affect local transformation efficiency. We investigated the landscape of transformation efficiency at various positions in the Saccharomyces cerevisiae genome and correlated these measurements with nucleosome positioning. We find that transformation efficiency shows a highly significant inverse correlation with relative nucleosome density. This correlation was lost when the nucleosome pattern, but not the underlying sequence was changed. Together, our results demonstrate a novel role for nucleosomes and also allow researchers to predict transformation efficiency of a target region and select spots in the genome that are likely to yield higher transformation efficiency

Diskriminacinių nuostatų įveika – būtina prielaida moterų dalyvavimui priimant ekonominius sprendimus

Although research has shown that women not only have the necessary education and professional qualifications, but also want and can hold positions in the highest decision-making bodies, gender disproportion in the boards of Lithuanian listed companies is obvious, since women have less favorable conditions than men since the beginning of their careers to pursue top management positions. One of the reasons for gender inequality in company boards is the prevalence of gender-based discriminatory attitudes in the professional environment both in Lithuania and in all EU countries, so women need to overcome many obstacles related to corporate behavior and business culture in order to realize their full professional potential. In order to find out the gender balance in Lithuanian listed companies, the opinion of companies‘ board members (women and men) about the situation and opportunities to become members of the board, the possibilities of increasing the participation of women in the boards, etc., an empirical study was carried out. Analysis of the results showed that, although in theory most respondents claim that there is no external barrier for competent women to be proposed and elected to the board of directors, publicly available, let there be covert, discriminatory clauses that create limiting factors for women’s participation in company boards, the overcoming of which is highly dependent on the activity of women themselves and the change in attitudes and attitudes available. We’ve summarized the challenges to achieving gender equity on boards and suggestions to address each of the challenges into four broad categories: boards themselves, women themselves, culture, and laws. One more challenge relates to the argument whether this idea of gender equity on Boards of Directors is even worth pursuing.Nors tyrimais įrodyta, kad moterys ne tik turi reikiamą išsimokslinimą ir profesinę kvalifikaciją, taip pat nori ir gali eiti pareigas aukščiausio lygio sprendimų priėmimo organuose, lyčių neproporcingumas Lietuvos biržinių bendrovių valdybose yra akivaizdus – nuo pat karjeros pradžios moterys turi mažiau palankias sąlygas nei vyrai siekti aukščiausio lygio vadovų pareigų. Viena iš lyčių netolygumo įmonių valdybose priežasčių – su lytimi susijusių diskriminacinių nuostatų paplitimas profesinėje aplinkoje tiek Lietuvoje, tiek visose ES šalyse, todėl moterys, siekdamos realizuoti visą savo profesinį potencialą, turi įveikti daugybę su bendrovių elgesiu ir verslo kultūra susijusių kliūčių. Siekiant išsiaiškinti lyčių pusiausvyrą Lietuvos biržinėse įmonėse, pačių bendrovių valdybų narių (moterų ir vyrų) nuomonę apie situaciją ir galimybes tapti valdybų nariais, moterų dalyvavimo valdybų veikloje didinimo galimybes ir pan., buvo atliktas empirinis tyrimas, kuris parodė, kad nors teoriškai dauguma respondentų teigia, kad kompetentingoms moterims nėra jokių išorinių kliūčių būti pasiūlytoms ir išrinktoms valdybos narėmis, visuomenėje dar gajos, tegul ir užslėptos, diskriminacinės nuostatos, sukuriančios moterų dalyvavimą bendrovių valdybų veiklose ribojančius veiksnius, kurių įveikimas labai priklauso nuo pačių moterų aktyvumo ir turimų nuostatų bei požiūrio kaitos

Adaptation to high ethanol reveals complex evolutionary pathways

Tolerance to high levels of ethanol is an ecologically and industrially relevant phenotype of microbes, but the molecular mechanisms underlying this complex trait remain largely unknown. Here, we use long-term experimental evolution of isogenic yeast populations of different initial ploidy to study adaptation to increasing levels of ethanol. Whole-genome sequencing of more than 30 evolved populations and over 100 adapted clones isolated throughout this two-year evolution experiment revealed how a complex interplay of de novo single nucleotide mutations, copy number variation, ploidy changes, mutator phenotypes, and clonal interference led to a significant increase in ethanol tolerance. Although the specific mutations differ between different evolved lineages, application of a novel computational pipeline, PheNetic, revealed that many mutations target functional modules involved in stress response, cell cycle regulation, DNA repair and respiration. Measuring the fitness effects of selected mutations introduced in non-evolved ethanol-sensitive cells revealed several adaptive mutations that had previously not been implicated in ethanol tolerance, including mutations in PRT1, VPS70 and MEX67. Interestingly, variation in VPS70 was recently identified as a QTL for ethanol tolerance in an industrial bio-ethanol strain. Taken together, our results show how, in contrast to adaptation to some other stresses, adaptation to a continuous complex and severe stress involves interplay of different evolutionary mechanisms. In addition, our study reveals functional modules involved in ethanol resistance and identifies several mutations that could help to improve the ethanol tolerance of industrial yeasts

Domestication and divergence of Saccharomyces cerevisiae beer yeasts

Whereas domestication of livestock, pets, and crops is well documented, it is still unclear to what extent microbes associated with the production of food have also undergone human selection and where the plethora of industrial strains originates from. Here, we present the genomes and phenomes of 157 industrial Saccharomyces cerevisiae yeasts. Our analyses reveal that today's industrial yeasts can be divided into five sublineages that are genetically and phenotypically separated from wild strains and originate from only a few ancestors through complex patterns of domestication and local divergence. Large-scale phenotyping and genome analysis further show strong industry-specific selection for stress tolerance, sugar utilization, and flavor production, while the sexual cycle and other phenotypes related to survival in nature show decay, particularly in beer yeasts. Together, these results shed light on the origins, evolutionary history, and phenotypic diversity of industrial yeasts and provide a resource for further selection of superior strains

SME's lending and Islamic finance. Is it a “win–win” situation?

Information asymmetry is a common feature that hinders lending to small and medium enterprises (SMEs). In the last decade, the growth in Islamic banks lending to SMEs was overwhelming to the extent that it prompted practitioners to regard this as a “win–win” situation. Unlike a conventional bank that mainly resorts to relationship banking to SMEs, an Islamic bank uses a Murabaha contract that creates a “collateral-by-contract” to the borrower. Such distinct lending approaches by the two types of banks have an implication on banks' cost curves that arise from differences in monitoring cost. In this article, we develop a two-stage competition model to investigate the growth in SMEs lending by Islamic banks. In our theoretical model Islamic and conventional banks compete with prices at the first stage (Bertrand framework) and with loan output at the second stage (Cournot framework). Our results reveal that in price competition an Islamic bank will gain market share initially due to its differentiated product. However, in the second stage, the amount of lending to SMEs by Islamic banks decreases due to market share competition

Approaches for advancing scientific understanding of macrosystems

The emergence of macrosystems ecology (MSE), which focuses on regional- to continental-scale ecological patterns and processes, builds upon a history of long-term and broad-scale studies in ecology. Scientists face the difficulty of integrating the many elements that make up macrosystems, which consist of hierarchical processes at interacting spatial and temporal scales. Researchers must also identify the most relevant scales and variables to be considered, the required data resources, and the appropriate study design to provide the proper inferences. The large volumes of multi-thematic data often associated with macrosystem studies typically require validation, standardization, and assimilation. Finally, analytical approaches need to describe how cross-scale and hierarchical dynamics and interactions relate to macroscale phenomena. Here, we elaborate on some key methodological challenges of MSE research and discuss existing and novel approaches to meet them