Anna Goc

Interleukin-27: Biological Properties and Clinical Application

Interleukin (IL)-27 is a novel cytokine secreted by stimulated antigen-presenting cells. Initial studies on the biology of IL-27 provided evidence for its role in the initiation of TH1 responses; however, subsequent work has indicated that IL-27 has broad inhibitory effects on TH1, TH2, and TH17 subsets of T cells as well as the expansion of inducible regulatory T cells. The involvement of IL-27 in the regulation of angiogenesis and antiviral response has also recently been reported. The aim of this review is to highlight the potential areas of IL-27 clinical application, especially the management of neoplastic and viral diseases as well as autoimmune disorders, including rheumatoid arthritis and multiple sclerosis. The review will also serve to elaborate on the molecular mechanisms involved in the expression of this cytokine and signaling from the IL-27 receptor.

Epigenetic, transcriptional and posttranscriptional regulation of the tyrosine hydroxylase gene

The activity of tyrosine hydroxylase (TH, EC 1.14.16.2) gene and protein determines the catecholamine level, which, in turn, is crucial for the organism homeostasis. The TH gene expression is regulated by near all possible regulatory mechanisms on epigenetic, transcriptional and posttranscriptional levels. Ongoing molecular characteristic of the TH gene reveals some of the cis and trans elements necessary for its proper expression but most of them especially these responsible for tissue specific expression remain still obscure. This review will focus on some aspects of TH regulation including spatial chromatin organization of the TH locus and TH gene, regulatory elements mediating basal, induced and cell‐specific activity, transcriptional elongation, alternative TH RNA processing, and the regulation of TH RNA stability in the cell.

Tissue-specific association of the human tyrosine hydroxylase gene with the nuclear matrix.

Association of the human tyrosine hydroxylase (TH) gene with the nuclear matrix was studied using bovine matrices from tissues differing in expression of the gene. An in vitro binding assay was performed with fragments encompassing the -2300/+2300 region of the human TH gene. All fragments bound to the nuclear matrix from the adrenal medulla but none bound to that from the liver. A computer search of the sequenced part of the studied region revealed putative matrix attachment regions (S/MAR) - one in the promoter and two in the first intron. The (TCAT)(n) microsatellite repeat included in one of the intronic S/MARs seems to influence the binding potential of the human TH gene to the nuclear matrices.

Wrażliwość odmian jarych i ozimych rzepaku na metale ciężkie i bakterie glebowe

Streszczenie Sprawdzono wplyw metali ciezkich (cynk, kadm, miedź, olow) oraz bakterii ryzosferowych na wzrost siewek Brassica napus L. Przeanalizowano trzy odmiany rzepaku: dwie jare – Belinda i Clipper oraz jedną ozimą – Kronos. Wykazano, ze porownywane odmiany charakteryzowaly sie zroznicowaną wrazliwością na obecnośc metali ciezkich w środowisku. Najbardziej wrazliwa na metale ciezkie byla odmiana ozima Kronos, natomiast najmniej – odmiana Clipper. Wszystkie analizowane szczepy ryzobakterii: Bacillus sp., Bacteroidetes bacterium, Flavobacterium sp., Luteibactor rhizovicina, Pseudomonas fluorescens, Serratia entomophila i Variovorax sp. stymulowaly wzrost siewek, zwlaszcza korzeni, odmian jarych rzepaku, zaś hamowaly w przypadku odmiany ozimej. Szczepy Bacteroidetes bacterium i Bacillus sp. najsilniej stymulowaly wzrost siewek odmiany Kronos, a Flavobacterium sp. siewek odmiany Belinda w obecności miedzi, cynku i kadmu. Wiekszośc badanych bakterii ulatwiala rozwoj siewek odmiany Clipper w środowisku zanieczyszczonym jonami cynku i olowiu.

Within and beyond the stringent response-RSH and (p)ppGpp in plants

Main conclusionPlant RSH proteins are able to synthetize and/or hydrolyze unusual nucleotides called (p)ppGpp or alarmones. These molecules regulate nuclear and chloroplast transcription, chloroplast translation and plant development and stress response.Homologs of bacterial RelA/SpoT proteins, designated RSH, and products of their activity, (p)ppGpp—guanosine tetra—and pentaphosphates, have been found in algae and higher plants. (p)ppGpp were first identified in bacteria as the effectors of the stringent response, a mechanism that orchestrates pleiotropic adaptations to nutritional deprivation and various stress conditions. (p)ppGpp accumulation in bacteria decreases transcription—with exception to genes that help to withstand or overcome current stressful situations, which are upregulated—and translation as well as DNA replication and eventually reduces metabolism and growth but promotes adaptive responses. In plants, RSH are nuclei-encoded and function in chloroplasts, where alarmones are produced and decrease transcription, translation, hormone, lipid and metabolites accumulation and affect photosynthetic efficiency and eventually plant growth and development. During senescence, alarmones coordinate nutrient remobilization and relocation from vegetative tissues into seeds. Despite the high conservancy of RSH protein domains among bacteria and plants as well as the bacterial origin of plant chloroplasts, in plants, unlike in bacteria, (p)ppGpp promote chloroplast DNA replication and division. Next, (p)ppGpp may also perform their functions in cytoplasm, where they would promote plant growth inhibition. Furthermore, (p)ppGpp accumulation also affects nuclear gene expression, i.a., decreases the level of Arabidopsis defense gene transcripts, and promotes plants susceptibility towards Turnip mosaic virus. In this review, we summarize recent findings that show the importance of RSH and (p)ppGpp in plant growth and development, and open an area of research aiming to understand the function of plant RSH in response to stress.