Grain Protein Content in Wheat: Genetics of the Character and Some Predictions for Its Improvement in Common Wheat

The results of studies on genetic control of the grain protein content in common wheat and the attempts of its improvement using traditional breeding approaches and methods of experimental mutagenesis and introgressive hybridization are presented. The evolution of the views on the genetic structure of the character is considered. Possible explanations are given to the fact that the attempts to significantly improve the character in question in common wheat cultivars have failed in spite of long-term genetic and selection studies. Possible lines of further investigation of genetic control of grain protein content and its increase in common wheat are discussed.__________Translated from Genetika, Vol. 41, No. 8, 2005, pp. 1013–1026.Original Russian Text Copyright © 2005 by Zlatska.     

Base Excision Repair of DNA: Glycosylases

The review considers the role of base excision repair in maintaining the constancy of genetic information in the cell. The genetic control and biochemical mechanism are described for the first stage of base excision repair, which is catalyzed by specific enzymes, DNA glycosylases.__________Translated from Genetika, Vol. 41, No. 6, 2005, pp. 725–735.Original Russian Text Copyright © 2005 by Korolev.     

Cardiolipin in energy transducing membranes

Cardiolipin is a phospholipid located exclusively in energy transducing membranes such as the bacterial cytoplasmic membrane and the inner membrane of mitochondria. It plays both a structural and a functional role in many multimeric complexes associated with these membranes. The role of cardiolipin in higher order organization of components of the mitochondrial respiratory chain revealed by a combined molecular genetic and biochemical approach is described.Translated from Biokhimiya, Vol. 70, No. 2, 2005, pp. 191–196.Original Russian Text Copyright © 2005 by Mileykovskaya, Zhang, Dowhan.This revised version was published online in April 2005 with corrections to the post codes.     

Hereditary Muscular Dystrophy: Bioengineering Approaches to Muscle Fiber Repair

Restoration of disturbed functions of the organs and tissues is the main task of contemporary genetic and cellular biotechnology, including genetic and cellular therapy. Duchenne dystrophy, one of the most widespread human genetic diseases, is at the same time the most extensively studied from the viewpoint of both genetic and histological changes leading to muscle fiber degeneration. Although many studies carried out on models, recognized analogous to Duchenne dystrophy, gave hopeful results, clinical tests with the use of developed methods gave no expected success and the rate of mortality from this disease amounts to 100%. Based on the world experience and analysis of the authors’ data, possible influence of the intensity of regeneration on success of genetic and cellular therapy has been considered.__________Translated from Ontogenez, Vol. 36, No. 4, 2005, pp. 310–318.Original Russian Text Copyright © 2005 by Semenova, Zelenina, Shafei, Golichenkov.     

Development of Transformation System in Monascus Purpureus using an Autonomous Replication Vector with Aureobasidin A Resistance Gene

To enhance the variety of genetic tools and thus to promote molecular genetic study, aureobasidin A and its resistance gene were adopted as a new marker system together with the incorporation of the Gateway system to facilitate the introduction of long heterologous DNA fragments into Monascus purpureus. The minimum inhibitory concentration of aureobasidin A against Monascus was 0.05 μg/ml and a transformation efficiency of 17 colonies/μg DNA was obtained by the protoplast-PEG method with the vector pAUR316, containing the aureobasidin A resistance gene. Southern analysis of the transformants confirmed that pAUR316 exists as an independent vector, demonstrating that the AMA1 sequence acts as the autonomous replication sequence in M. purpureus. Through the use of the Gateway system, a polyketide synthase gene (7.8 kbp) responsible for citrinin biosynthesis was introduced. As a result, the transformants showed 1.5-fold higher production of citrinin than the wild-type strain. Received 21 September 2005; Revisions requested 5 October 2005; Revisions received 2 November 2005; Accepted 3 November 2005     

Genetic diversity in Isoetes yunguiensis, a rare and endangered endemic fern in China

Isoetes yunguiensis is an endangered and endemic fern in China. Field survey indicated that only one population and no more than 50 individuals occur in the wild. The genetic variation of 46 individuals from the population remaining at Pingba (Guizhou Province, China) was assessed by Random Amplified Polymorphic DNA (RAPD) finger-printing. Twelve primers were screened from sixty ten-bp arbitrary primers, and a total of 95 DNA fragments were scored. Of these, 62.1% were polymorphic loci, which indicated that high level genetic variation existed in the natural population. The accumulation of genetic variation in the history of the taxon and the apparent minimal reduction effect on genetic diversity following destruction of habitat might be responsible for the high level genetic diversity presently remaining in the I. yunguiensis population. However, with the continuing decrease of population size, the genetic diversity will gradually be lost. We suggest that the materials from the extant population should be used for re-establishment of the populations. Translated from Journal of Wuhan University (Natural Sciences Edition), 2005, 51(6): 767–770 [译自: 武汉大学学报 (理学版)]     

Identification of the gene whose mutation leads to the morphological changes in the hypocotyl of <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis>

The results of genetic and molecular genetic analysis of line 176 of Arabidopsis thaliana with reduced hypocotyls obtained from a previously developed collection of insertion mutants, are presented. The examined mutation proved to be recessive and based on a single insertion of the T-DNA vector pLD3 into the A. thaliana genome. Computer-aided analysis of the amplified in TAIL-RCR DNA region adjacent to the left border of the insertion revealed a putative site of T-DNA insertion, the 2.5-kb At2g09920 gene located in the long arm of chromosome 2, near the centromere.Translated from Genetika, Vol. 41, No. 2, 2005, pp. 166–170.Original Russian Text Copyright © 2005 by Ogarkova, Tomilov, Tomilova, Pogorelko, Tarasov.     

Role of Genetic Processes in Modification Variability. Prophecy of B.L. Astaurov

In his pioneering work on mutation tetraptera in Drosophila melanogaster, B.L. Astaurov discovered spontaneous modifications based on variability in gene expression. This new approach to the phenomenon of modifications should be considered as the first stimulus to development of the general theory of variability. Contemporary classification of variability based predominantly on phenomenology encounters many contradictions. The same specific molecular mechanisms may be responsible, for example, for both hereditary and nonhereditary variability depending on the taxonomic status. Some mechanisms responsible for both mutations and modifications or for mutations, recombination, and ontogenetic variability have been considered from this viewpoint. It may well be more productive to consider different types of variability with respect to the main genetic processes: replication and expression of genetic material.__________Translated from Ontogenez, Vol. 36, No. 4, 2005, pp. 274–279.Original Russian Text Copyright © 2005 by Inge-Vechtomov.     

Identification of the Gene Whose Mutation Leads to the Appearance of Recessive Lethal Germlings in <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis>

The data are presented on genetic and molecular-genetic analysis of a mutant from the collection of morphological insertion mutants of Arabidopsis thaliana we obtained earlier, which belongs to the phenotypic class of recessive lethal germlings. A nucleotide DNA sequence, 147 bp in size, was identified, which adheres to the left border area of T-DNA insertion. The site of localization of the insertion was determined using computer analysis.__________Translated from Ontogenez, Vol. 36, No. 3, 2005, pp. 222–224.Original Russian Text Copyright © 2005 by Ogarkova, Tomilov, Tomilova, Tarasov.     

The effect of oxidative stress on nitrosomethylurea-induced mutagenesis in sunflower <Emphasis Type="Italic">Helianthus annuus</Emphasis> L.

The effect of hyberbaric oxygenation on mutagenicity of nitrosomethylurea (NMU) was examined. It was shown that in the regimes studied, hyperbaric oxygenation enhances the NMU mutagenic effect on the plastid genetic material of sunflower. Possible mechanisms of the increase of NMU-induced mutagenesis by hyperbaric oxygenation are discussed.Translated from Genetika, Vol. 41, No. 1, 2005, pp. 63–70.Original Russian Text Copyright © 2005 by Usatov, Mashkina, Guskov.     

Mechanisms of human cell protection associated with genetic polymorphism

Systems ensuring protection of human cells against endogenous and exogenous mutagenic factors are considered in terms of genetic polymorphism. Some protection mechanisms are described, including those connected with capturing free radicals, biotransformation of xenobiotics, excision repair of DNA damage (excision of nitrous bases, nucleotides, mismatch repair). A special section is devoted to some issues of using antimutagens in context of genetic polymorphism. The problem of adaptive response is discussed, providing evidence for independence (in some cases) of DNA repair systems and the formation of adaptive response. Some results of the author obtained many years ago but still relevant are presented.__________Translated from Genetika, Vol. 41, No. 4, 2005, pp. 520–535.Original Russian Text Copyright © 2005 by Zasukhina.     

Meeting report for the 4th Annual Complex Trait Consortium Meeting: From QTLs to Systems Genetics

The fourth annual meeting of the Complex Trait Consortium (CTC) was held in Groningen, the Netherlands on June 26–29, 2005. This meeting, which set a new attendance record, followed three previous and highly successful meetings. The focus at this meeting was on continued resource development and the exiting new field of systems genetics, the integration and anchoring of multi-dimensional data-types to underlying genetic variation. A new aspect at the meeting was the three-minute, ‘come see my poster’ presentations that generated significant interaction at the poster sessions. If the 2005 meeting is an indicator of things to come, future meetings promise to offer even more exciting research efforts to integrate high-throughput biological measurements with genetic variation to unravel the mechanisms responsible for inter-individual variation.     

RAPD and ISSR analyses of regenerated pea <Emphasis Type="Italic">Pisum sativum</Emphasis> L. plants

Long-term pea callus cultures of different genotypes (mutants R-9 and W-1 and cultivar Viola) were used to regenerate plants (generation R₀). The regenerants displayed changes both in qualitative and in quantitative traits. The most dramatic morphological alterations and complete sterility were observed in regenerants of the cultivar Viola. To estimate the genetic differences, regenerants were compared with the original lines with the use of RAPD (random amplified polymorphic DNA) and ISSR (inter simple sequence repeat) analyses. The extent of divergence varied among regenerants and depended mostly on the original genotype. The genetic difference from the original line was no more than 1% in W-1 regenerants, 0.7–5.3% in R-9 regenerants, and 10–15% in sterile regenerants of the cultivar Viola. The genetic variation of plants regenerated from a callus culture maintained for ten years did not exceed that of plants obtained from a culture maintained for two years.Translated from Genetika, Vol. 41, No. 1, 2005, pp. 71–77.Original Russian Text Copyright © 2005 by Kuznetsova, Ash, Hartina, Gostimskij.     

Macrogeographic genetic variability in the Gastropod Mollusk <Emphasis Type="Italic">Littorina sitkana</Emphasis> from the Northwest Pacific

Variation at four highly polymorphic allozyme loci (inorganic pyrophosphatase, peptidase, and two esterase loci) was examined in 25 settlements of the marine snail Littorina sitkana (Mollusca, Gastropoda). The sampling localities covered a wide part of the species range: from the Peter the Great Bay (the Sea of Japan) at the southwest to the Mednyi Island (Commander Islands) at the northeast. Like other littorines lacking the pelagic stage, L. sitkana was characterized by significant genetic differentiation (G _ST for the pooled sample was 0.310). Cluster analysis and nonmetric multidimensional scaling conducted on a matrix of pairwise genetic distances between all of the settlements studied revealed four genetically different groups: southern Primorye, northern Prymorye, Sakhalin, and Kuril-Commanders. The population-genetic structure of the L. sitkana settlements is similar to that described by the isolation-by-distance and stepping-stone models: the geographic and the genetic distances between the most settlements examined are distinctly correlated.Translated from Genetika, Vol. 41, No. 3, 2005, pp. 374–384.Original Russian Text Copyright © 2005 by Zaslavskaya, Pudovkin.     

A comparison of the genetic diversity in Dipteronia sinensis Oliv. and Dipteronia dyeriana Henry

Dipteronia is an endemic genus to China and includes only two species, Dipteronia sinensis and D. dyeriana. Based on random amplified polymorphic DNA (RAPD) markers, a comparative study of the genetic diversity and genetic structure of Dipteronia was performed. In total, 128 and 103 loci were detected in 17 D. sinensis populations and 4 D. dyeriana populations, respectively, using 18 random primers. These results showed that the proportions of polymorphic loci for the two species were 92.97% and 81.55%, respectively, indicating that the genetic diversity of D. sinensis was higher than that of D. dyeriana. Analysis, based on similarity coefficients, Shannon diversity index and Nei gene diversity index, also confirmed this result. AMOVA analysis demonstrated that the genetic variation of D. sinensis within and among populations accounted for 56.89% and 43.11% of the total variation, respectively, and that of D. dyeriana was 57.86% and 42.14%, respectively. The Shannon diversity index and Nei gene diversity index showed similar results. The abovementioned characteristics indicated that the genetic diversity levels of these two species were extremely similar and that the interpopulational genetic differentiation within both species was relatively high. Analysis of the genetic distance among populations also supported this conclusion. Low levels of interpopulational gene flow within both species were believed to be among the leading causes for the above-mentioned phenomenon. The correlation analysis between genetic and geographical distances showed the existence of a remarkably significant correlation between the genetic distance and the longitudinal difference among populations of D. sinensis (p < 0.01), while no significant correlation was found between genetic and geographical distances among populations of D. dyeriana. This indicated that genetic distance was correlated with geographical distances on a large scale rather than on a small scale. This result may be related to differences in the selection pressure on species by their habitats with different distribution ranges. We suggest that in situ conservation efforts should focus on establishing more sites to protect the natural populations and their habitats. Ex situ conservation efforts should focus on enhancing the exchange of seeds and seedlings among populations to facilitate gene exchange and recombination, and to help conserve genetic diversity. __________ Translated from Acta Phytoecologica Sinica, 2005, 29(5): 785–792 [译自: 植物生态学报, 2005, 29(5): 785–792]     

Preliminary Observations of Population Genetics and Relatedness of the Broadnose Sevengill Shark,Notorynchus cepedianus,in Two Northeast Pacific Estuaries

The broadnose sevengill shark, Notorynchus cepedianus, a common coastal species in the eastern North Pacific, was sampled during routine capture and tagging operations conducted from 2005–2012. One hundred and thirty three biopsy samples were taken during these research operations in Willapa Bay, Washington and in San Francisco Bay, California. Genotypic data from seven polymorphic microsatellites (derived from the related sixgill shark, Hexanchus griseus) were used to describe N. cepedianus genetic diversity, population structure and relatedness. Diversity within N. cepedianus was found to be low to moderate with an average observed heterozygosity of 0.41, expected heterozygosity of 0.53, and an average of 5.1 alleles per microsatellite locus. There was no evidence of a recent population bottleneck based on genetic data. Analyses of genetic differences between the two sampled estuaries suggest two distinct populations with some genetic mixing of sharks sampled during 2005–2006. Relatedness within sampled populations was high, with percent relatedness among sharks caught in the same area indicating 42.30% first-order relative relationships (full or half siblings). Estuary-specific familial relationships suggest that management of N. cepedianus on the U.S. West Coast should incorporate stock-specific management goals to conserve this ecologically important predator.     

Genetic analysis of foot-and-mouth disease virus serotype A of Indian origin and detection of positive selection and recombination in leader protease- and capsid-coding regions

The leader protease (L^pro) and capsid-coding sequences (P1) constitute approximately 3 kb of the foot-and-mouth disease virus (FMDV). We studied the phylogenetic relationship of 46 FMDV serotype A isolates of Indian origin collected during the period 1968–2005 and also eight vaccine strains using the neighbour-joining tree and Bayesian tree methods. The viruses were categorized under three major groups — Asian, Euro-South American and European. The Indian isolates formed a distinct genetic group among the Asian isolates. The Indian isolates were further classified into different genetic subgroups (<5% divergence). Post-1995 isolates were divided into two subgroups while a few isolates which originated in the year 2005 from Andhra Pradesh formed a separate group. These isolates were closely related to the isolates of the 1970s. The FMDV isolates seem to undergo reverse mutation or convergent evolution wherein sequences identical to the ancestors are present in the isolates in circulation. The eight vaccine strains included in the study were not related to each other and belonged to different genetic groups. Recombination was detected in the L^pro region in one isolate (A IND 20/82) and in the VP1 coding 1D region in another isolate (A RAJ 21/96). Positive selection was identified at aa positions 23 in the L^pro (P<0.05; 0.046*) and at aa 171 in the capsid protein VP1 (P<0.01; 0.003**).     

The role of genetic factors in human radioresistance

The role of genetic factors in the development of chronic radiation disease (CRD), mostly caused by occupational external -exposure, was evaluated. The data of molecular genetic survey of a cohort of 985 workers at the nuclear power plant, the Mayak PA, were analyzed. Among the genetic markers tested, an association between the haptoglobin (Hp) genetic system and the development of CRD was established. It was demonstrated that the contribution of genetic factors to the CRD onset was realized not within the whole, but in a relatively narrow dose interval (70 to 400 cGy), i.e., was relative. Furthermore, at equal irradiation doses, relatively higher risk of CRD was observed among the Hp 2-2 phenotype carriers (1.96) compared to lower risk among the Hp 1-1 and Hp 2-1 phenotype carriers (0.64). It was shown that with the increase of the irradiation dose, genotypic differences in the CRD frequency decreased to the point of their complete disappearance. Comparison of the roles of the genetic factors in the onset of such deterministic irradiation effect as CRD, with their roles in the onset of lung cancer in tobacco smokers revealed similar patterns. A scheme of the relationships between the effector intensity and the differences in the genetically determined radioresistance is presented. The data obtained do not support the idea that the survivals of the atomic bombing of Hiroshima and Nagasaki were the most radioresistant individuals, who are not representative for evaluating the radiation risk.Translated from Genetika, Vol. 41, No. 1, 2005, pp. 85–92.Original Russian Text Copyright © 2005 by Telnov.     

Genetic Demography of the Kuznetsk Basin Population: Changes in Marriage Assortativeness with Respect to Ethnicity and Age in the Belovo City Population with Time

A genetic demographic study has been performed in the city of Belovo with the use of the data on marriages contracted there in 1970 and 1994–1999. Marriage assortativeness with respect to age has been found to be the strongest and remain unchanged during the lifetime of one generation (r = 0.730 in 1970 and r = 0.801 in 1994–1999). Monoethnic marriages were substantially more frequent than interethnic ones in the Belovo population during the period studied, although the ethnic marriage assortativeness considerably decreased (K = 0.386 in 1970 and K = 0.141 in 1994–1999). Panmixia has been observed in the Russian population of Belovo. Other Eastern Slavs (Ukrainians and Belarussians) are characterized by negative marriage assortativeness and panmixia; positive marriage assortativeness has been found in other ethnic groups.__________Translated from Genetika, Vol. 41, No. 7, 2005, pp. 938–942.Original Russian Text Copyright © 2005 by Lavryashina, Ulyanova.     

Development of a Biochip for Analyzing Polymorphism of the Biotransformation Genes

Large-scale population studies, diagnosis of genetic predisposition to a broad range of multifactorial diseases, and screening of polymorphic loci associated with individual drug resistance need efficient, accurate, and rapid techniques for identifying many mutations. One of the most promising techniques is hybridization on an oligonucleotide microarray (biochip). The efficiency of this method in assessing genetic polymorphism was demonstrated using an example of mutations in CYP1A1, CYP2D6, GSTM1, GSTT1, NAT2, CYP2C9, CYP2C19, and MTHFR. The biochip constructed provides a convenient tool for pharmacogenetic research.__________Translated from Molekulyarnaya Biologiya, Vol. 39, No. 3, 2005, pp. 403–412.Original Russian Text Copyright © 2005 by Glotov, Nasedkina, Ivaschenko, Urasov, Surzhikov, Pan’kov, Chudinov, Baranov, Zasedatelev.