Evolution of the X-linked Zinc Finger Gene and the Y-linked Zinc Finger Gene in Primates

We have sequenced the partial exon of the zinc finger genes (ZFX and ZFY) in 5 hominoids, 2 Old World monkeys, 1 New World monkey, and 1 prosimian. Among these primate species, the percentage similarities of the nucleotide sequence of the ZFX gene were 96-100% and 91.2-99.7% for the ZFY gene. Of 397 sites in the ZFX and ZFY gene sequences, 20 for ZFX gene and 42 for ZFY gene were found to be variable. Substitution causes 1 amino acid change in ZFX, and 5 in ZFY, among 132 amino acids. The numbers of synonymous substitutions per site (Ks) between human and the chimpanzee, gorilla and orangutan for ZFY gene were 0.026, 0.033, and 0.085, respectively. In contrast, the Ks value between human and hominoid primates for the ZFX gene was 0.008 for each comparison. Comparison of the ZFX and ZFY genes revealed that the synonymous substitution levels were higher in hominoids than in other primates. The rates of synonymous substitution per site per year were higher in the ZFY exon than in the SRY exon, and higher in the ZFY exon than in the ZFY intron, in hominoid primates.     

Targeted Expression of the only Zinc Finger Gene in Transgenic Mice is Associated with Impaired Mammary Development

The only zinc finger (OZF) gene encodes a protein consisting mainly of 10 zinc finger motifs of the Krüppel type of yet unknown function. To potentially assess its in vivo role, mammary targeted deregulation of the expression of the murine gene was performed in transgenic mice using a goat -casein-based transgene. Mammary expression of the transgene was observed in the 11 lines obtained. In three expressing lines, this expression was tissue-specific and developmentally regulated. Further analysis of mice from two expressing lines revealed that transgene-homozygous females could not sustain full growth of their pups. This phenotype was associated with an impaired mammary gland development noticeable only after mid-gestation. It was characterised by an increase of the adipocyte to acini ratio and low or absence of fat globules within these acini compared to non-transgenic control animals. These transgenic observations strongly suggest that OZF is active in the mammary gland, interfering with the lactation process and thus that the described transgenic mice could be useful models to search for the cellular partner(s) of this protein.     

High Prevalence and Species Diversity of Helicobacter spp. Detected in Wild House Mice

PCR diagnostics detected 100% prevalence of Helicobacter in 425 wild house mice (Mus musculus) from across central Europe. Of seven species identified, the five most frequent were Helicobacter rodentium (78%), H. typhlonius (53%), H. hepaticus (41%), H. bilis (30%), and H. muridarum (1%). Double infections were more common (42%) than single (30%) and triple (21%) infections. Wild house mice could be considered potential reservoirs of Helicobacter strains for both humans and other vertebrates.     

A Role for Widely Interspaced Zinc Finger (WIZ) in Retention of the G9a Methyltransferase on Chromatin

G9a and GLP lysine methyltransferases form a heterodimeric complex that is responsible for the majority of histone H3 lysine 9 mono- and di-methylation (H3K9me1/me2). Widely interspaced zinc finger (WIZ) associates with the G9a-GLP protein complex, but its role in mediating lysine methylation is poorly defined. Here, we show that WIZ regulates global H3K9me2 levels by facilitating the interaction of G9a with chromatin. Disrupting the association of G9a-GLP with chromatin by depleting WIZ resulted in altered gene expression and protein-protein interactions that were distinguishable from that of small molecule-based inhibition of G9a/GLP, supporting discrete functions of the G9a-GLP-WIZ chromatin complex in addition to H3K9me2 methylation.     

Prdm16 Is Required for the Maintenance of Brown Adipocyte Identity and Function in Adult Mice

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Mitochondrial DNA Diversity of Modern,Ancient and Wild Sheep (Ovis gmelinii anatolica) from Turkey: New Insights on the Evolutionary History of Sheep

In the present study, to contribute to the understanding of the evolutionary history of sheep, the mitochondrial (mt) DNA polymorphisms occurring in modern Turkish native domestic (n = 628), modern wild (Ovis gmelinii anatolica) (n = 30) and ancient domestic sheep from Oylum Höyük in Kilis (n = 33) were examined comparatively with the accumulated data in the literature. The lengths (75 bp/76 bp) of the second and subsequent repeat units of the mtDNA control region (CR) sequences differentiated the five haplogroups (HPGs) observed in the domestic sheep into two genetic clusters as was already implied by other mtDNA markers: the first cluster being composed of HPGs A, B, D and the second cluster harboring HPGs C, E.To manifest genetic relatedness between wild Ovis gmelinii and domestic sheep haplogroups, their partial cytochrome B sequences were examined together on a median-joining network. The two parallel but wider aforementioned clusters were observed also on the network of Ovis gmelenii individuals, within which domestic haplogroups were embedded. The Ovis gmelinii wilds of the present day appeared to be distributed on two partially overlapping geographic areas parallel to the genetic clusters that they belong to (the first cluster being in the western part of the overall distribution). Thus, the analyses suggested that the domestic sheep may be the products of two maternally distinct ancestral Ovis gmelinii populations.Furthermore, Ovis gmelinii anatolica individuals exhibited a haplotype of HPG A (n = 22) and another haplotype (n = 8) from the second cluster which was not observed among the modern domestic sheep. HPG E, with the newly observed members (n = 11), showed signs of expansion. Studies of ancient and modern mtDNA suggest that HPG C frequency increased in the Southeast Anatolia from 6% to 22% some time after the beginning of the Hellenistic period, 500 years Before Common Era (BCE).     

Neutral Polymorphisms in Putative Housekeeping Genes and Tandem Repeats Unravels the Population Genetics and Evolutionary History of Plasmodium vivax in India

The evolutionary history and age of Plasmodium vivax has been inferred as both recent and ancient by several studies, mainly using mitochondrial genome diversity. Here we address the age of P. vivax on the Indian subcontinent using selectively neutral housekeeping genes and tandem repeat loci. Analysis of ten housekeeping genes revealed a substantial number of SNPs (n = 75) from 100 P. vivax isolates collected from five geographical regions of India. Neutrality tests showed a majority of the housekeeping genes were selectively neutral, confirming the suitability of housekeeping genes for inferring the evolutionary history of P. vivax. In addition, a genetic differentiation test using housekeeping gene polymorphism data showed a lack of geographical structuring between the five regions of India. The coalescence analysis of the time to the most recent common ancestor estimate yielded an ancient TMRCA (232,228 to 303,030 years) and long-term population history (79,235 to 104,008) of extant P. vivax on the Indian subcontinent. Analysis of 18 tandem repeat loci polymorphisms showed substantial allelic diversity and heterozygosity per locus, and analysis of potential bottlenecks revealed the signature of a stable P. vivax population, further corroborating our ancient age estimates. For the first time we report a comparable evolutionary history of P. vivax inferred by nuclear genetic markers (putative housekeeping genes) to that inferred from mitochondrial genome diversity.     

The Cytoplasmic Zinc Finger Protein ZPR1 Accumulates in the Nucleolus of Proliferating Cells

The zinc finger protein ZPR1 translocates from the cytoplasm to the nucleus after treatment of cells with mitogens. The function of nuclear ZPR1 has not been defined. Here we demonstrate that ZPR1 accumulates in the nucleolus of proliferating cells. The role of ZPR1 was examined using a gene disruption strategy. Cells lacking ZPR1 are not viable. Biochemical analysis demonstrated that the loss of ZPR1 caused disruption of nucleolar function, including preribosomal RNA expression. These data establish ZPR1 as an essential protein that is required for normal nucleolar function in proliferating cells.     

安徽省野生兰花资源多样性研究

通过对安徽省野生兰花资源的调查,发现安徽省野生兰花资源主要集中于皖西大别山山区及皖南山区,共有野生兰花资源34属、56种,是华东地区盛产地之一,也是全国乃至世界兰花资源的重要来源;以少种属和寡种属为主;生活类型以地生为主;垂直分布格局上呈一定规律分布;安徽省兰科植物属分布区类型可以划分为9类型3变型,明显的温带和亚热带过渡的特点;另外就安徽省的兰花资源现状提出了保护建议。     

Analysis of Starch Gene Diversity in the Wild Relatives of Oryza sativa

Genetic loci influencing traits important to humans have been selected during crop domestication. The starch properties of rice influence the ease of cooking and attractiveness of rice as a human food. Starch biosynthesis genes likely to influence starch properties in the grain were compared in wild and domesticated rice genotypes. Sequence variation was investigated in starch biosynthesis gene exons that have been reported to have a direct influence on rice amylose content, gelatinization temperature, and amylopectin chain length. Exons 6 and 10 of GBSSI, exon 8 of SSIIa and exons 11, 13, 14 and 16 of SBEIIb were amplified and sequenced from 13 wild Oryza species encompassing genome types AA to HHJJ. Thirty two single nucleotide polymorphisms (SNPs) were identified in the exons of GBSSI; 176 in exon 8 of SSIIa, and 43 in SBEIIb, giving a total of 251 SNPs among the species. Eighty six of these SNP caused changes in the encoded amino acid, of which 28 were missense mutations that affected highly conserved amino acids within the protein sequence of GBSSI, SSIIa or SBEIIb. Two indels were identified in Potamophila parviflora, a close relative of Zizania palustris, a North American native wild rice. Most of the nucleotide variations and non-conservative changes were observed in the genomes other than the AA genome species. This represents a genetic resource for use in rice starch manipulation. The impact of human selection at these loci can be deduced by comparison of modern cultivated genotypes with their wild progenitors.     

Evolutionary Diversity of the Mechanisms Providing the Establishment of Left-Right Asymmetry in Metazoans

Russian Journal of Developmental Biology - Left-right asymmetry is an important feature of the body plan of bilaterian animals. Malformations of the left-right axis result in pathologies of varying...     

Genetic recombination variation in wild Robertsonian mice: on the role of chromosomal fusions and Prdm9 allelic background

Despite the existence of formal models to explain how chromosomal rearrangements can be fixed in a population in the presence of gene flow, few empirical data are available regarding the mechanisms by which genome shuffling contributes to speciation, especially in mammals. In order to shed light on this intriguing evolutionary process, here we present a detailed empirical study that shows how Robertsonian (Rb) fusions alter the chromosomal distribution of recombination events during the formation of the germline in a Rb system of the western house mouse (Mus musculus domesticus). Our results indicate that both the total number of meiotic crossovers and the chromosomal distribution of recombination events are reduced in mice with Rb fusions and that this can be related to alterations in epigenetic signatures for heterochromatinization. Furthermore, we detected novel house mouse Prdm9 allelic variants in the Rb system. Remarkably, mean recombination rates were positively correlated with a decrease in the number of ZnF domains in the Prdm9 gene. The suggestion that recombination can be modulated by both chromosomal reorganizations and genetic determinants that control the formation of double-stranded breaks during meiosis opens new avenues for understanding the role of recombination in chromosomal speciation.     

Changes in Monoamine Turnover in the Brain of Cachectic Mice Bearing Colon-26 Tumor Cells

Abstract: Patients with cancer cachexia often suffer from psychiatric disorders. In the present study, we investigated the changes in monoaminergic activities in the brain in tumor-bearing mice with reference to the development of cachexia. Two clones, clone-5 (noncachectic clone) and clone-20 (cachectic clone), derived from the murine Colon-26 adenocarcinoma cell line (Nippon Roche Research Center), were inoculated subcutaneously at 1 × 10⁶ cells/0.2 ml into the right lower back of BALB/c mice. In clone-20 mice, body weight and locomotor activity decreased significantly 10–15 days after tumor inoculation. The levels of noradrenaline, dopamine, and 3,4-dihydroxyphenylacetic acid showed no significant change among the three groups. The noradrenaline turnover rate in clone-20 mice was increased in cerebral cortex, hypothalamus, and midbrain. The 5-hydroxytryptamine turnover rate in clone-20 mice was increased in hippocampus, cerebral cortex, midbrain, and pons-medulla oblongata. In contrast, the dopamine turnover rate in clone-20 mice was decreased markedly in hippocampus, cerebral cortex, striatum, hypothalamus, and cerebellum. There was no significant change in amine turnover between control and clone-5 mice except for dopamine in hippocampus, cerebral cortex, and striatum and 5-hydroxytryptamine in striatum. No significant change in the levels of amino acids in the brain was observed among the three groups of mice. It is concluded that some of the psychiatric disorders from which cancer cachectic patients suffer might be ascribable to changes in monoaminergic activities in the brain.