Suppression of the Testis-Specific Transcription of the ZBTB32 and ZNF473 Genes in Germ Cell Tumors.

The family of genes containing C2H2 zinc finger domains, which has more than 700 members, is one of the largest in the genome. Of particular interest are C2H2 genes with potential tissue-specific transcription, which determine the functional properties of individual cell types, including those associated with pathological processes. The aim of this work was to identify C2H2 family genes with tissue-specific transcription and analyze changes in their activity during tumor progression. To search for these genes, we used four databases containing data on gene transcription in human tissues obtained by RNA-Seq analysis. The analysis showed that, although the major part of the C2H2 family genes is transcribed in virtually all tissues, a group of genes has tissue-specific transcription, with most of the transcripts being found in the testis. After having compared all four databases, we identified nine such genes. The testis-specific transcription was confirmed for two of them, namely ZBTB32 and ZNF473, using quantitative PCR of cDNA samples from different organs. A decrease in ZBTB32 and ZNF473 transcription levels was demonstrated in germ cell tumors. The studied genes can serve as candidate markers in germ cell tumors.

A Universal Tumor-Specific Promoter for Cancer Gene Therapy.

An artificial double tandem tumor-specific promoter based on survivin and human telomerase reverse transcriptase gene promoters was constructed. Studies in in vitro and ex vivo therapeutic systems showed that the designed promoter exhibits a high activity in tumor cells, which is comparable to the activity of the CMV constitutive promoter.

[Fundamentally low reproducibility in molecular genetic cancer research].

The review discusses the causes of multiple failures in cancer treatment, which might primarily result from the excessive variability of cancer genomes. They are capable of changing their spatial and temporal architecture during tumor development. The key reasons of irreproducibility of biomedical data and the presumable means for improvement of therapeutic results aiming at targeting the most stable tumor traits are suggested.

[An immunological study of secreted human polymeric immunoglobulins' J-peptide tissue specificity].

Contents of J-peptide of secreted human polymeric immunoglobulins may vary considerably with different pathologies, reflecting the state of the adaptive immune system. In this work assessed the content of J-peptide in various tissues of healthy people to use as a baseline for studies related to the change in the content of J-peptide in pathologies.

Identification and mapping of ten new potential insulators in the FXYD5-COX7A1 region of human chromosome 19q13.12.

A positive-negative selection system revealed 10 potential insulators able to block enhancer interaction with promoter in the 10(6) bp human chromosome 19 region between genes FXYD5 and COX7A1. Relative positions of insulators and genes are in accord with the hypothesis that insulators subdivide genomic DNA into independently regulated loop domains.

[Regulatory potential of S/MAR elements in transient expression].

S/MARs (scaffold/matrix attachment regions) are the DNA regions that are involved in the interaction with the nuclear matrix and are identified by in vitro methods. According to the available information, S/MARs possess an insulating activity, i.e., the ability to block the interaction between the enhancer and promoter in vivo, and are, probably, intact insulators or their fragments. Nevertheless, there is still no direct proof for this correspondence. To obtain additional information on the insulator activity of S/MARs, we selected five DNA fragments of different lengths and affinities for the nuclear matrix from the previously constructed library of S/MARs and tested their ability to serve as insulators. Two of five elements exhibited an insulator (enhancer-blocking) activity upon the transient transfection of CHO cells. None of the S/MARs displayed either promoter or enhancer/silencer activities in these cells.

Recombinant destabilase-lysozyme: synthesis de novo in E. coli and action mechanism of the enzyme expressed in Spodoptera frugiperda.

Destabilase-lysozyme (DL) from salivary gland secretion of the medicinal leech (Hirudo medicinalis) is as a member of the invertebrate lysozyme family, which sharply differs from other lysozyme families. In this study, DL lysozyme function was confirmed during expression of a gene encoding DL in Escherichia coli. Several constructs of the expression vectors pKK OmpA and pET-3A with or without bacterial, leech, or yeast signal peptides (SP) were used. The use of a construct without signal peptide genes resulted in normal growth of the transformed cells. Transformation of E. coli cells with the constructs containing SP was accompanied by the disruption of the forming cells. The use of the expression vector pET-32 LTC-System for production of DL as a fusion protein with thioredoxin also resulted in normal cell growth. However, specific activity of DL isolated from such cells was significantly lower than that of enzyme purified from extracts of Spodoptera frugiperda cells, which were infected with the baculovirus vector carrying DL cDNA. It is shown that the action mechanism of invertebrate lysozyme does not differ from that of other families: recombinant DL from S. frugiperda extracts catalyzed cleavage of synthetic substrate, hexamer of N-acetylglucosamine, to di- and tetramers, which is typical for enzymatic function of other lysozyme families.

Solitary HERV-K LTRs possess bi-directional promoter activity and contain a negative regulatory element in the U5 region.

Reporter gene analysis of HERV-K solitary long terminal repeats (LTRs) showed that they retain detectable activity in human teratocarcinoma cells, and can direct the transcription in both orientations relative to the reporter gene. Deletion analysis demonstrated the possible existence of alternative promoters within the LTR as well as a silencer-like element in the U5 region. Our results indicate also that all-trans-retinoic acid is capable of modulating expression of the reporter gene directed by a HERV-K LTR in NT2/D1 cells.

Destabilase from the medicinal leech is a representative of a novel family of lysozymes.

Intrinsic lysozyme-like activity was demonstrated for destabilase from the medicinal leech supported by (1) high specific lysozyme activity of the highly purified destabilase, (2) specific inhibition of the lysozyme-like activity by anti-destabilase antibodies, and (3) appreciable lysozyme-like activity in insect cells infected with recombinant baculoviruses carrying cDNAs encoding different isoforms of destabilase. Several isoforms of destabilase constitute a protein family at least two members of which are characterized by lysozyme activity. The corresponding gene family implies an ancient evolutionary history of the genes although the function(s) of various lysozymes in the leech remains unclear. Differences in primary structures of the destabilase family members and members of known lysozyme families allow one to assign the former to a new family of lysozymes. New proteins homologous to destabilase were recently described for Caenorhabditis elegans and bivalve mollusks suggesting that the new lysozyme family can be widely distributed among invertebrates. It remains to be investigated whether the two enzymatic activities (isopeptidase and lysozyme-like) are attributes of one and the same protein.