In the domain model of eukaryotic genome organization, the functional unit of the genome, along with the relevant regulatory elements, is considered to be a gene or a gene family. In hot-blooded vertebrate animals, the domains of a- and b-globin genes are positioned at different chromosomes and are organized and regulated in different fashion. In cold-blooded animals, in particular in tropical fish Danio rerio, a- and b globin genes are located in a common gene cluster.
View Article and Find Full Text PDFUsing native chromatin immunoprecipitation (N-ChIP) followed by TaqMan RT-PCR quantitative analysis we have determined the profiles of histone acetylation and histone methylation within the alpha-globin gene domain before and after switching of embryonic globin genes expression. The results obtained do not support a supposition that the inactivation of the embryonic alpha-type globin gene pi in erythroid cells of the adult lineage is mediated via formation of an inactive chromatin domain. On the other hand we have demonstrated that suppression of the gene pi activity in erythroid cells of adult lineage correlates with the decrease of the histone acetylation level within the embryonic subdomain of the alpha-globin gene domain.
View Article and Find Full Text PDFMol Biol (Mosk)
February 2006
We have developed a technique for mapping the sites of DNA attachment to the nuclear matrix by hybridization of nuclear matrix DNA with an oligonucleotide array. The latter was made by immobilization of 60-mer oligonucleotides distributed within the area under study with a 2 Kb step on nylon filter. Using this approach we have analyzed the mode of interaction of a 100 Kb fragment of chicken chromosome 16 including the alpha-globin gene domain with the nuclear matrix.
View Article and Find Full Text PDFThe specific features of genome domains lacking distinct boundaries are considered. These domains cannot be mapped by testing extended genome regions for nuclease sensitivity and thereby differ from structural domains determined at the level of DNA folding in chromatin. Yet they possess the properties of typical functional domains, containing a gene or several coordinated genes along with a complex of cis-regulatory elements, which control these genes.
View Article and Find Full Text PDFGene activity regulation at the level of genome domains is considered with special emphasis on locus control regions (LCR), which are thought to act as dominant regulatory elements providing for the active state of tissue-specific gene domains. Detailed analysis was made of experimental data on the organization and function of mammalian beta-globin gene LCR. On recent evidence, this LCR is necessary for high-level expression of the globin genes, but not for the active state of the domain.
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