Activity and subcellular distribution of protein kinase dependent on adenosine 3':5'-monophosphate in liver from normal and adrenalectomized rats.

We have examined whether glucocorticoids control the activity and (or) the subcellular distribution of protein kinase dependent on cyclic AMP (adenosine 3':5'-monophosphate), since they influence cyclic-AMP-dependent responses to other hormones. Protein kinase activity was determined in rat liver homogenates and subcellular fractions, nuclear, large granular, microsomal and supernatant obtained by differential sedimentation in 0.25 M sucrose. 63% of the tissue protein kinase activity detected in absence of cyclic AMP reside in the particulate fractions. Upon addition of exogenous cyclic AMP, protein kinase activity is stimulated 1.8, 1.2, 1.2 and 4.5-fold in nuclear, large granular, microsomal and supernatant fractions, respectively. Under these conditions, 66% of tissue activity are found in the supernatant fraction. The activity sensitive to exogenous cyclic AMP resolves into a major (84%) cytosoluble and a minor (16%) nucleomicrosomal component. The latter activity resists elution with isotonic saline and is increased in the presence of Triton X-100. Three groups of rats were studied: control and adrenalectomized with or without cortisol treatment. In whole liver homogenates, both protein kinase activity detected in absence of exogenous cyclic AMP and sensitivity of the enzyme to cyclic AMP were comparable in all groups. Moreover, the distribution patterns of proteins kinase activity amoung the fractions were essentially the same in all groups of animals, whether or not particles had been treated with Triton X-100. Finally, in cell-free experiments, glucocorticoids alone or in combination with their intracellular receptor did not modify protein kinase activity of rat liver. Thus the results reported do not support the possibility that glucocorticoids influence cyclic AMP-dependent protein kinase in rat liver. Yet, this study provides data, not available before, on subcellular distribution of this enzyme in rat liver.     

A global assessment of Echinococcus multilocularis infections in domestic dogs: proposing a framework to overcome past methodological heterogeneity

Echinococcus multilocularis, the aetiological agent of human Alveolar Echinococcosis, is transmitted between small mammals and wild or domestic canids. Dogs infected with E. multilocularis as dead-end hosts. Whereas E. multilocularis infections in wild hosts and humans have been well-studied in recent decades, infections in domestic dogs are sparsely reported. This literature review and meta-analysis highlighted gaps in the available data and provided a re-assessment of the global distribution of domestic dog E. multilocularis infections. We found 46 published articles documenting the prevalence of E. multilocularis in domestic dogs from 21 countries across Europe, Asia and North America. Apparent prevalence estimates ranged from 0.00% (0.00–0.33%) in Germany to 55.50% (26.67–81.12%) in China. Most studies were conducted in areas of high human Alveolar Echinococcosis. By accounting for reassessed diagnostic sensitivity and specificity, we estimated true prevalence in a subset of studies, which varied between 0.00% (0.00–12.42%) and 41.09% (21.12–65.81%), as these true prevalence estimates were seldom reported in the articles themselves. Articles also showed a heavy emphasis on rural dogs, dismissing urban ones, which is concerning due to the role urbanisation plays in the transmission of zoonotic diseases, especially those utilising pets as definitive hosts. Lastly, population studies on canine Alveolar Echinococcosis were absent, highlighting the relative focus on human rather than animal health. We thus developed a framework for investigating domestic dog E. multilocularis infections and performing risk assessment of dog-associated transmission to fill the gaps found in the literature.     

Redox-Dependent Control of FOXO/DAF-16 by Transportin-1

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Highlights? FOXO forms redox-sensitive, disulfide-dependent complexes with several proteins ? Transportin-1 binds to FOXO via a disulfide and regulates its nuclear localization ? Redox and insulin signaling govern FOXO nuclear localization via distinct pathways ? Redox control of longevity protein FOXO/DAF-16 is evolutionarily conserved     

Achiral Nucleotide Analogs: 5,5-Disubstituted Pyrimidines Related to Barbituric Acid

Abstract

Achiral nucleotide analogs are of potential interest in origin of life studies. Four new 5,5-diphosphoethylpyrimidine analogs were prepared by condensation of urea or guanidine with a, a-di(2-[ethoxy-I-ethoxy]ethyl)malononitrile or a, a-di(2-[ethoxy-1-ethoxy]ethyl)ethyl cyanoacetate respectively, followed by removal of the protecting groups and bisphosphorylation. Oligomers of two potentially complementary analogs have been prepared. Interactions between these oligomers appear to be weak in aqueous solution.     

Biodeterioration of Mayan buildings at uxmal and tulum,Mexico

Uxmal and Tulum are two important Mayan sites in the Yucatan peninsula. The buildings are mainly composed of limestone and grey/black discoloration is seen on exposed walls and copious greenish biofilms on inner walls. The principal microorganisms detected on interior walls at both Uxmal and Tulum were cyanobacteria; heterotrophic bacteria and filamentous fungi were also present. A dark‐pigmented mitosporic fungus and Bacillus cereus, both isolated from Uxmal, were shown to be acidogenic in laboratory cultures. Cyanobacteria belonging to rock‐degrading genera Synechocystis and Gloeocapsa were identified at both sites. Surface analysis previously showed that calcium ions were present in the biofilms on buildings at Uxmal and Tulum, suggesting the deposition of biosolubilized stone. Apart from their potential to degrade the substrate, the coccoid cyanobacteria supply organic nutrients for bacteria and fungi, which can produce organic acids, further increasing stone degradation.     

Introgression and the fate of domesticated genes in a wild mammal population

When domesticated species are not reproductively isolated from their wild relatives, the opportunity arises for artificially selected variants to be re‐introduced into the wild. However, the evolutionary consequences of introgression of domesticated genes back into the wild are poorly understood. By combining high‐throughput genotyping with 25 years of long‐term ecological field data, we describe the occurrence and consequences of admixture between a primitive sheep breed, the free‐living Soay sheep of St Kilda, and more modern breeds. Utilizing data from a 50 K ovine SNP chip, together with forward simulations of demographic scenarios, we show that admixture occurred between Soay sheep and a more modern breed, consistent with historical accounts, approximately 150 years ago. Haplotype‐sharing analyses with other breeds revealed that polymorphisms in coat colour and pattern in Soay sheep arose as a result of introgression of genetic variants favoured by artificial selection. Because the haplotypes carrying the causative mutations are known to be under natural selection in free‐living Soay sheep, the admixture event created an opportunity to observe the outcome of a ‘natural laboratory’ experiment where ancestral and domesticated genes competed with each other. The haplotype carrying the domesticated light coat colour allele was favoured by natural selection, while the haplotype associated with the domesticated self coat pattern allele was associated with decreased survival. Therefore, we demonstrate that introgression of domesticated alleles into wild populations can provide a novel source of variation capable of generating rapid evolutionary changes.