[Human intra-intronic minisatellite UPS29 associated with neurological diseases regulates reporter gene EGFP expression depending on cell type].

Earlier, it was established that polymorphism of minisatellite UPS29 located in one of introns of human gene CENTB5 (ACAP3) was associated with Parkinson's disease and epilepsy. The main aim of this work was to elucidate if that minisatellite could regulate reporter gene activity, and if such activity was tissue (cell)-specific. To this end there was used transient transfection of HeLa cells, mouse embryonal carcinoma line F9, and rat astrocytes cultures with plasmides which contained reporter gene EGFP under eukaryotic promoter ROSA26 and different allelles of minisatellite UPS29. It was found that UPS29 possessed enhancer-like activity in neuronal type cells.

[CENTB5 gene expression in human and mouse].

Centaurin beta5 with unclear function belongs to protein family of centaurins. Human centaurin beta5 is encoded by gene CENTB5 whose intron 14-15 contains low variable minisatellite UPS29, and mouse homolog CENTB5 in analogous intron contains imperfect microsatellite repeat (CATG)19. Earlier we found the association between an occurrence of short UPS29 alleles with some forms of Parkinson disease and epilepsy. Besides this, both human and mice CENTB5 are localized in the same synteny group with SCNN1D and ACOT7 genes which are known to be expressed predominantly in nervous system. Mutations in these genes are connected with neurodegenerative processes and epilepsy. It is known that intra-intronic sequences can modulate genes of their location and neighbor and even remote genes. Using RT-PCR we carried out simultaneous analysis of CENTB5, SCNN1D and ACOT7 genes expression. Potential possibility of human intra-intronic tandem repeat UPS29 and of mouse intra-intronic tandem repeat (CATG)19 to regulate/modulate CENTB5, SCNN1D and ACOT7 activity was evaluated in silico. It was found that all these genes were expressed in all studied organs and tissues. It is suggested that minisatellite locus UPS29 can regulate an activity of CENTB5, SCNN1D and ACOT7 in nervous system cells.

[Transgenerational transmission of bovine satellite DNA in transgenic mice].

Genetical, cytogenetical and molecular analysis was made for 5 generations of mice transgenic for bovine satellite DNA (Sat). In all cases transgenic mice were generated by crosses of transgenic males and females with normal (CBA x C57B1) mice. No abnormalities in the founder development were noticed. A normal (near 50 %) ratio of transgenic and nontransgenic offsprings was observed in blastocysts. However, profound differences occurred in the rate of transgene bearing offsprings, depending on the sex of grandparents rather than of parents. The grandfather Sat transmission resulted in the appearance of 0-52.4 % transgenic grandchildren, whereas the grandmother transmission ended in the theoretically expected rate. This means that stabilization of transsatellite took place upon the female germ line transmission (a positive grandmother effect). It is essential that in hemizygous transsatellite mice Sat integration led to the occurrence of mammary tumors, inflammation of uterine horns, and infringement of mother care of transgenic females. Simultaneous FISH and G-banding showed Sat to be localized in the internal region of chromosome 12 near Pax 9 and Brms 11 genes. Commonly, these genes are implicated in tumorigenesis as their expression decreases. Thus, a kind of silencing effect of these genes' expression may be supposed.

[Instability of repetitive units of foreign centromeric satellite DNA in transgenic mice and transfected cells]. / Analiz nestabil'nosti povtoriaiushchikhsia edinits chuzherodnoi tsentromernoi satellitnoi DNK u transgennykh myshei i v transfektnykh kletkakh.

Cytologically detectable instability of centromeric satellite DNA may cause hereditary disorders in human. To study the mechanisms of such instability, two transgenic mouse lines and 11 clones of transfected F9 mouse embryonic teratocarcinoma cells were obtained with the 3.8-kb repetitive unit (Sat) of Bos taurus satellite DNA IV. Intergeneration and somatic instability of exogenous satellite DNA (satDNA) was observed in transgenic mice and transfected cells as a change in nucleotide sequence of an internal Sat region approximately 1000 bp in size. Since Sat was in the hemizygous state in both cases by the experimental protocol, the instability was attributed to intra-allelic processes. Intergeneration instability probably took place in the premeiotic period of gametogenesis or in early embryo development and led to prenatal death of transgenic embryos after at least one generation. No direct or inverse correlation was observed between methylation and instability of Sat. The results testify that submicroscopic changes in highly repetitive noncoding DNA sequences may already affect the genome function in higher eukaryotes.