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Serotonin reduces the behavior tolerance of Caenorhabditis elegans of the N2 wild-type strain (swimming induced by the mechanical stimulus) to a temperature of 36 degrees C. The sensitivity to the serotonin influence on the behavior thermotolerance remains intact in strains with null mutations of mod-1 (ok103) and ser-1 (ok345) serotonin receptor genes, and is almost completely lost in the ser-4 (ok512) strain with null mutation in the gene of the SER-4 serotonin receptor, which is a homologue of 5-HT1 mammalian serotonin receptor. In addition, nematodes of the ser-4 (ok512) strain have high behavior thermotolerance in the absence of the exogenous serotonin compared to the N2 strain. These data indicate the involvement of the ser-4 gene in the serotonin regulation of the tolerance of C. elegance nervous system functions to hyperthermia.

A family of closely related genes, named the d4 family, has been previously identified in mammals. It comprises three genes encoding structurally related proteins. The hallmark of the family is d4 domain--a double-paired finger motifthat consists of two tandemly arranged PHD finger domains. These genes are expressed in various tissues and at various developmental stages. Two of those, neuro-d4 and cer-d4, are strictly neurospecific and their expression is developmentally regulated. Another gene, ubi-d4/Requiem is ubiquitously expressed in all embryonic and adult tissues at the same levels. d4 family genes are evolutionary conserved. Human, mouse, rat, and chicken d4 genes have been cloned. The only d4-like gene was found in the genome of nematode C. elegans. The sole member of d4 family was identified also in the genome of D. melanogaster. However, d4 genes are not believed to be present in the genomes of prokaryotes and yeast. This review describes genomic organization and expression ofd4family genes in different organisms.

Now it is known that 18 neurological inherited diseases connected with mutations of multiple insertion of one amino acid residue in protein sequence. Therefore, studying the functional role of such simple motifs is an important task in biology. In this work we have investigated how often homorepeats, i.e. runs of a single amino acid residue, of 6 amino acid residues long as well as simple motifs consisting from two amino acid residues of 6 residues long situated in any position occur in three eukaryotic well studied proteomes: Homo sapiens, Drosophila melanogaster, Caenorhabditis elegans. It turns out that many simple motifs occur very often. The occurrence for each motif can be found at our site: http://antares.protres.ru/motifs_six_residues.html. One can suggest that such short similar motifs are responsible for the common functions for nongomologous, unrelated proteins from different organisms.

Nematodes Caenorhabditis elegans is a widely used model for studying the genetic and molecular mechanisms that determine the lifespan. The choice between the two vital program strategies of adult hermaphrodite C. elegans--normal aging and matritcide (programmed death), is largely affected by the availability of food, and also depends on a variety of stresses. We decided to test the hypothesis that, in line with the phenoptosis theory, oxidative stress increases probability of the programmed death of the whole organism. It is shown that high concentrations of paraquat (strong mitochondrial stress) significantly increase the propensity to matricide. In this case, mutants with a reduced antioxidant capacity of mitochondria (nnt) are more sensitive to the reagent. On the other hand, the concentrations of paraquat, necessary for the manifestation of this effect, are toxic to the offspring, while at low concentrations matricide of mutant worms and wild-type worms occurs with equal frequency. Therefore it is safe to conclude that oxidative stress is not the key initiating mechanism of matricide under normal conditions.

The review describes possible role of kinesins in development of coronary heart disease and efficacy of treatment with statins. Fourty five kinesins are represented in human body making up a superfamily of universal and simplest motor proteins which are expressed almost in all tissues. Level of kinesin 6 is 5% higher than expression of other kinesins in some segments of coronary arteries and it is relatively low in organs playing unknown role in susceptibility to atherosclerosis. As a result of several genoms wide association studies the role of polymorphic marker Thr719Arg of kinesin 6 gene in development of ischemic heart disease, myocardial infarction, and in efficacy of therapy with statins was revealed.

Mitochondrial transhydrogenase catalyzes the reaction H(+)(out) + NADP(+) + NADH = NAD(+) + NADPH + H(+)(in). The maintenance of the NADPH pool increases the mitochondrial antioxidant potential. Therefore, according to the commonly adopted free radical theory of aging, ablation of the transhydrogenase gene should reduce the life span. However, contrary to this reasoning, the life span of Caenorhabditis elegans nematodes with null mutations in the gene does not differ from that in wild-type worms. This fact indicates that free radical damage of mitochondria is not associated with aging. Meta analysis of data on the life span in mice possessing a spontaneous mutation in the transhydrogenase gene shows that a lack of this enzyme does not accelerate aging in mammals either. The heart is the tissue with the highest transhydrogenase production rate, and it is likely that this enzyme contributes to the protection of cardiac myocytes from oxidative stress.

Genes of Arabidopsis thaliana, Orysa sativa, Caenorhabditis elegans, Homo sapiens have been studied by computer analysis. The average intron and exon lengths in genes of these organisms decreases with increase of intron number in genes. The length of introns and exons in A. thaliana and O. sativa genes is change with increase of intron number in genes by high coefficient of correlation. Linear dependence between the sum of exon lengths and intron number in genes increased proportionally to number of gene introns. The average length of introns and genes of human depend on density of genes in DNA.

Aging of organism is a complex process, however it is succeeded to mark out of new evolution-conservative genetic component of longevity and aging. Among the most perspective problems, connecting with this component, there are search of longevity genes in model animals, investigations of mechanisms of environment influence on aging speed (meal quality, light and temperature regimes, irradiation and hypergravity), revealing of aging biomarkers and genes, determined exceptional centenarians in human, and non-genetics methods of aging correction. The most impressive results observed in gerontogene search. In yeast and nematodes there are mutations, which increase maximum lifespan on 10 times, in Drosophila and mice--about 2 times. Nevertheless, genes regulated the aging speed by indirection, controlling organism resistance to damages by exogenous and endogenous stresses.

The authors review literary and own data on programmed death of cells (PDC) in animals and plants, molecular mechanisms of apoptosis in animals, and key PDC regulating genes.

Current views on the role of RNA interference in controlling the expression and transposition of mobile genes in the eukaryotic genome are considered in connection with a recollected work resulting in the discovery of retrotransposons.