Effects of the Cc2d1a/Freud-1 Knockdown in the Hippocampus of BTBR Mice on the Autistic-Like Behavior,Expression of Serotonin 5-HT1A and D2 Dopamine Receptors,and CREB and NF-kB Intracellular Signaling

Biochemistry (Moscow) - The mechanisms of autism are of extreme interest due to the high prevalence of this disorder in the human population. In this regard, special attention is given to the...     

Comparative genetic analysis of the hexaploid wheat Triticum petropavlovskyi Udasz. et Migusch. and Triticum aestivum L

A poorly studied species of hexaploid wheat Triticum petropavlovskyi Udacz. et Migusch. was compared with common wheat Triticum aestivum L. by means of monosomic and genetic analyses of F2 hybrids. Triticum petropavlovskyi was found to carry 13 dominant genes determining its morphological and physiological characters and regular bivalent conjugation of chromosomes. These genes were allelic to the respective genes of common wheat and were located in the same chromosomes. The modes of gene interaction were also the same. There was simple dominance for most genes studied and complementary interaction for the genes of hybrid dwarfism and hybrid necrosis. Triticum petropavlovskyi had the following dominant genes: Hg (downy glume); Rg1 (red glume color); Hl (downy leaf); Hn (downy node); Pa (pubescent auricles); Q (speltlike ears); D1 (grass-clump dwarfism); Ne1 (hybrid necrosis); Ph1 and Ph2 (genes of bivalent conjugation preventing homoeologous chromosomes from pairing); and Vrn1, Vrn2, Vrn3, and Vrn4 (genes of the spring habit). The gene Vrn1, which caused an increase in ear emergence time and a pronounced response to vernalization, was poorly expressed. T. petropavlovskyi was earlier demonstrated to have a species-specific gene P or Eg (elongated glume), which was not allelic to the gene Eg of the tetraploid T. polonicum L. The data obtained indicate that T. petropavlovskyi has originated from T. aestivum via mutations.     

Mineral salt-dependent inhibition of light emission from the luminescent microorganism Escherichia coli Z9051

The influence of some mineral salts on the recombinant strain Escherichia coli Z9051 was investigated. It was shown that the composition (NaCl, Na2SO4, MgCl2 and MgSO4) and concentration (5 and 10%) of the salts substantially affect the expression of genes for the luminescence system of light-emitting bacteria cloned in the plasmid under the control of the lac-promoter. In some cases, the luminescence level of the microorganism in the presence of salts was similar to the luminescence level under catabolite repression by glucose, the more strong influence of the salts exceeding the effect of catabolite repression. The possibility of adaptation of the genetically modified microorganism to the salinity factor is discussed.     

The role of medial septal area in the neural control over hibernation

Hibernation (winter sleep) is a kind of unique adaptive behavior of small mammals subjected to fine and complex central control. One of the most promising approaches to this problem is a search for the mechanisms providing brain control under conditions of a sharp decrease in temperature, (virtually, to zero) and metabolic rate. Studies conducted at the Laboratory of System Organization of Neurons under the supervision of Professor O.S. Vinogradova confirmed the hypothesis of the special role of the septohippocampal system in the control of winter sleep. Together with a brief characterization of hibernation in general, the data obtained at the Laboratory are also summarized in the review. The experimental evidence for the role of the medial septal area as a "sentry post" in hibernation is presented.     

Genetic analysis of spontaneous suppressors of the pho85 mutation in the yeast Saccharomyces cerevisiae

Chaperones are known to play an important role in complexation of cyclin-dependent kinases with cyclins. In yeast cells growing in the presence of phosphate, cyclin-dependent kinase Pho85p and cyclin Pho80p form a complex and phosphorylate activator Pho4p. As a result, Pho4p is exported from the nucleus, and the PHO5 gene is not transcribed. The mutations suppressing the pho85 mutation were analyzed in order to identify genes which code for chaperones involved in the formation of the Pho80p-Pho85p complex in the presence of environmental phosphate. Dominant mutations DSP1, DSP2, and DSP4-6 were found. It is shown that the DSP1 gene is 2.1 cM away from the PHO85 gene on chromosome XVI and probably coincides with the EGD1 gene coding for a chaperone.     

Identification of catalytically active groups of lipoxygenase from wheat germ

Catalytically active groups of lipoxygenase in wheat germs have been identified. Blocking of catalytically active groups by specific reagents, dependence of the enzyme activity on pH, enthalpy of ionization of pK1 and pK2, the enzyme photoinactivation allowed to make a conclusion that imidasole and hydroxyl groups take part in lipoxygenase catalytic cycle.     

Correlation between cataleptic freezing and prestimulation inhibition of the startle reflex in rats

In rats of GC strain bred for predisdposition to cataleptic freezing, a significant negative correlation between the duration of freezing and the level of prepulse inhibition (PPI) of the startle reflex, has been found. Besides, in a group of GC rats specific by their "nervousness" and jumpiness, there was also a negative correlation between the duration of freezing and the habituation to the startle reflex. None of this correlation have been found in Wistar rats. Since impairment of the PPI and habituation of the startle reflex is considered to be characteristic of schizophrenia, it is believed than cataleptic freezing in the GC rats may be used as a model of schizophrenic psychopathology.     

Age-specific morphological-functional characteristics of the rabbit's hippocampal neurons during conditioning

Formation of trace rhythm recruitment (an analogue of conditioned time reflex) was studies in CA3 hippocampal neurons of alert young (less than one year), old (54-65 months), and very old rabbits after a prolonged (10-20 min) electro-cutaneous stimulation of a forelimb with the frequency of 0.5-1 Hz. Comparative analysis of neuronal spike activity in young and old rabbits showed that in the late ontogeny the number of spontaneously active neurons was significantly decreased, the proportion of slowly firing neurons increased, the interspike intervals and intervals between spike groups became longer, the number of spikes in a group reduced. The ability of hippocampal neurons to acquire and reproduce the rhythm of the previous stimulation declined with age. No appropriate rhythms were found in neurons of very old animals. A nonspecific increase in neuronal baseline activity was observed in old rabbits after the stimulation. Deterioration of morphological structures of hippocampal neurons and glial cells may explain the impairment of mnestic processes in late ontogeny.     

A comparison of the immune response induced by DNA or by an inactivated vaccine against tick-borne encephalitis

BALB/c mice were immunized with recombinant plasmid DNA pSVK3-ENS1 and pcDNAI-NS3 containing, respectively, genes E-NS1 and NS3 of tick-borne encephalitis (TBE) virus. Antibodies to TBE virus proteins were detected in the blood sera of the immunized animals by the method of the enzyme immunoassay. Though the titers of virus-specific antibodies in the sera of mice immunized with protein vaccines exceeded those registered after immunization with DNA vaccines, essential protective immunity was observed after the use of both vaccines.