A spherical model of the discrimination of the emotional expressions of a schematic human face]

The four-dimensional spherical emotional space was constructed by multidimensional scaling of visually perceived differences between emotional expressions of schematic faces. In this spherical model Euclidean distances between the points representing the schematic faces are directly proportional to perceived differences of emotional expressions. Three angles of the four-dimensional sphere correspond to specific characteristics of emotions, such as emotional modality (joy, fear, anger, etc.), intensity of emotions, and emotional fullness (saturation). At the same time Cartesian coordinates represent excitations in the neuronal channels encoding line orientations. It was shown that the structure of the emotional space is similar to the structure of color space, i.e., emotional modality corresponds to color hue, emotional intensity to brightness, and emotional fullness to color saturation. The obtained evidence suggests the common mechanisms of information coding in the visual system.     

New Photoreactive Cleavable Reagents with Trifluoromethyldiazirine Group

Photoreactive crosslinking reagents that simultaneously contain a trifluoromethyldiazirine and an o-nitrobenzyl groups were synthesized for the first time. Photochemical properties of the reagents were studied, and the possibility of separate activation of the diazirine group and o-nitrobenzyl linker was shown.     

Trifluoromethyldiazirine-Containing dUTP: Synthesis and Application in DNA/Protein Crosslinking

Abstract

The 5-[N-(4-(3-(trifluoromethyl)-3H-diazirin-3-yl)benzoyl)-3-aminoallyl]-2′-deoxyuridine-5′-triphosphate was synthesized via acylation of 5-aminoallyl-2′-deoxyuridine-5′-triphosphate with 4-(3-(trifluoromethyl)-3H-diazirin-3-yl)benzoate N-hydroxysuccinimide. It was used for the preparation of 30 bp ATFMD-DNA coding for promoter sequence. UV-Irradiation (365 nm) of the specific complex of this duplex and E. coli RNA polymerase leads to the effective crosslinking DNA with all protein subunits.     

External diversity is restrained by internal conservatism: New nudibranch mollusc contributes to the cryptic species problem

Cryptic species are an important concept of modern biodiversity studies and a potential basis for immensely increasing the amount of biological diversity worldwide; however, the conceptual grounds of cryptic species still need to be refined. Here, using a remarkable example from marine invertebrates, the case of a species complex of common large‐sized nudibranchs of the genus Dendronotus in European waters is presented, which is relevant for the ongoing cryptic species discussion. Based on extensive sampling in the seas of Northern Hemisphere from United Kingdom to the Sea of Japan, a morphological and molecular framework is constructed for understanding the diversity of European Dendronotus nudibranchs. The present study discovered notable multilevel character diversity within the common Dendronotus “frondosus” species complex. This implies the highest degree of variation of external characters with parallel colour patterns among different species and significantly constrained conservatism of internal characters. The molecular data are congruent with the stable differences in the internal features and confirm the presence of three distinct species in this complex. While two species were already known, the third species is evidently new, based on morphological and molecular evidence and is described here as Dendronotus europaeus sp. n. In the light of multilevel character diversity, the general problem of plausibility of the distinction and practical usage of the terms “cryptic” and “pseudocryptic” species is discussed.     

Genetic Structure of the Volga–Ural and Central Asian Populations Inferred from the Data on Alu Polymorphism

NineAlu loci (Ya5NBC5, Ya5NBC27, Ya5NBC148, Ya5NBC182, YA5NBC361, ACE, ApoA1, PV92, TPA25) were analyzed in six ethnic populations (Trans-Ural Bashkirs, Tatars-Mishars, Mordovians-Moksha, Mountain Maris, Udmurts, and Komi-Permyaks) of the Volga–Ural region and in three Central Asian populations (Uzbeks, Kazakhs, and Uigurs). All Alu insertions analyzed appeared to be polymorphic in all populations examined. The frequency of insertion varied from 0.110 in Mountain Maris at the Ya5NBC5 locus to 0.914 in Tatars at the ApoA1 locus. The data on the allele frequency distribution at nine loci point to the existence of substantial genetic diversity in the populations examined. The value of the observed heterozygosity averaged over nine Alu insertions varied from 0.326 in Mountain Maris to 0.445 in Kazakhs and Uigurs. The level of the interpopulation genetic differences for the Volga–Ural population (F _st = 0.061) was higher than for the populations of Central Asia (F _st = 0.024), Europe (F _st = 0.02), and Southeastern Asia (F _st = 0.018). The populations examined were highly differentiated both in respect of linguistic characteristics and the geographical position. The data obtained confirmed the effectiveness of the marker system used for the assessment of genetic differentiation and the relationships between the ethnic groups.     

Network, cellular and molecular mechanisms of plasticity in simple nervous systems

In the present study we will try to single out several principles of the nervous system functioning essential for describing mechanisms of learning and memory basing on our own experimental investigation of cellular mechanisms of memory in the nervous system of gastropod molluscs and literature data: main changes in functioning due to learning occur in effectivity of synaptic inputs and in the intrinsic properties of postsynaptic neurons; due to learning some synaptic inputs of neurons selectively change its effectivity due to pre- and postsynaptic changes, but the induction of plasticity always starts in postsynapse, maintaining of long-term memory in postsynapse is also shown; reinforcement is not related to activity of the neural chain receptor-sensory neuron-interneuron-motoneuron-effector; reinforcement is mediated via activity of modulatory neurons, and in some cases can be exerted by a single neuron; activity of modulatory neurons is necessary for development of plastic modifications of behavior (including associative), but is not needed for recall of conditioned responses. At the same time, the modulatory neurons (in fact they constitute a neural reinforcement system) are necessary for recall of context associative memory; changes due to learning occur at least in two independent loci in the nervous system. A possibility for erasure of memory with participation of nitroxide is experimentally and theoretically based.     

A new agonist of the erythropoietin receptor, Epobis, induces neurite outgrowth and promotes neuronal survival

Apart from its hematopoietic activity, erythropoietin (EPO) is also known as a tissue-protective cytokine. In the brain, EPO and its receptor are up-regulated in response to insult and exert pro-survival effects. EPO binds to its receptor (EPOR) via high- and low-affinity binding sites (Sites 1 and 2, respectively), inducing conformational changes in the receptor, followed by the activation of downstream signaling cascades. Based on the crystal structure of the EPO:EPOR(2) complex, we designed a peptide, termed Epobis, whose sequence encompassed amino acids from binding Site 1. The present study shows that the Epobis peptide specifically binds to EPOR and induces neurite outgrowth from primary neurons in an EPOR-expression dependent manner. Furthermore, Epobis promoted the survival of hippocampal and cerebellar neuronal cultures after kainate treatment and KCl deprivation, respectively. Thus, we identified a new functional agonist of EPOR with the potential to promote neuroregeneration and neuroprotection.