Nejvíce citovaný článek - PubMed ID 10611221
Sex chromosome replacement is frequent in many vertebrate clades, including fish, frogs, and lizards. In order to understand the mechanisms responsible for sex chromosome turnover and the early stages of sex chromosome divergence, it is necessary to study lineages with recently evolved sex chromosomes. Here we examine sex chromosome evolution in a group of African cichlid fishes (tribe Tropheini) which began to diverge from one another less than 4 MYA. We have evidence for a previously unknown sex chromosome system, and preliminary indications of several additional systems not previously reported in this group. We find a high frequency of sex chromosome turnover and estimate a minimum of 14 turnovers in this tribe. We date the origin of the most common sex determining system in this tribe (XY-LG5/19) near the base of one of two major sub-clades of this tribe, about 3.4 MY ago. Finally, we observe variation in the size of one sex-determining region that suggests independent evolution of evolutionary strata in species with a shared sex-determination system. Our results illuminate the rapid rate of sex chromosome turnover in the tribe Tropheini and set the stage for further studies of the dynamics of sex chromosome evolution in this group.
- MeSH
- cichlidy * genetika MeSH
- fylogeneze MeSH
- jezera MeSH
- mitochondriální DNA genetika MeSH
- molekulární evoluce MeSH
- pohlavní chromozomy genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Tanzanie MeSH
- Názvy látek
- mitochondriální DNA MeSH
Biotic stresses threaten to destabilize global food security and cause major losses to crop yield worldwide. In response to pest and pathogen attacks, plants trigger many adaptive cellular, morphological, physiological, and metabolic changes. One of the crucial stress-induced adaptive responses is the synthesis and accumulation of plant secondary metabolites (PSMs). PSMs mitigate the adverse effects of stress by maintaining the normal physiological and metabolic functioning of the plants, thereby providing stress tolerance. This differential production of PSMs is tightly orchestrated by master regulatory elements, Transcription factors (TFs) express differentially or undergo transcriptional and translational modifications during stress conditions and influence the production of PSMs. Amongst others, microRNAs, a class of small, non-coding RNA molecules that regulate gene expression post-transcriptionally, also play a vital role in controlling the expression of many such TFs. The present review summarizes the role of stress-inducible TFs in synthesizing and accumulating secondary metabolites and also highlights how miRNAs fine-tune the differential expression of various stress-responsive transcription factors during biotic stress.
- Klíčová slova
- miRNAs, pathogen infection, pest attack, plant specialized/secondary metabolites, transcription factors,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Root, shoot, and lateral meristems are the main regions of cell proliferation in plants. It has been proposed that meristems might have evolved dedicated transcriptional networks to balance cell proliferation. Here, we show that basic helix-loop-helix (bHLH) transcription factor heterodimers formed by members of the TARGET OF MONOPTEROS5 (TMO5) and LONESOME HIGHWAY (LHW) subclades are general regulators of cell proliferation in all meristems. Yet, genetics and expression analyses suggest specific functions of these transcription factors in distinct meristems, possibly due to their expression domains determining heterodimer complex variations within meristems, and to a certain extent to the absence of some of them in a given meristem. Target gene specificity analysis for heterodimer complexes focusing on the LONELY GUY gene targets further suggests differences in transcriptional responses through heterodimer diversification that could allow a common bHLH heterodimer complex module to contribute to cell proliferation control in multiple meristems.
- Klíčová slova
- Biological sciences, Molecular plant pathology, Natural sciences, Plant biology,
- Publikační typ
- časopisecké články MeSH
Genes influencing oocyte maturation may be valuable for predicting their developmental potential, as well as discerning the mechanistic pathways regulating oocyte development. In the presented research microarray gene expression analysis of immature and in vitro matured porcine oocytes was performed. Two groups of oocytes were compared in the study: before (3 × n = 50) and after in vitro maturation (3 × n = 50). The selection of viable oocytes was performed using the brilliant cresyl blue (BCB) test. Furthermore, microarrays and RT-qPCR was used to analyze the transcriptome of the oocytes before and after IVM. The study focused on the genes undergoing differential expression in two gene-ontology groups: "Cellular response to hormone stimulus" and "Cellular response to unfolded protein", which contain genes that may directly or indirectly be involved in signal transduction during oocyte maturation. Examination of all the genes of interest showed a lower level of their expression after IVM. From the total number of genes in these gene ontologies ten of the highest change in expression were identified: FOS, ID2, BTG2, CYR61, ESR1, AR, TACR3, CCND2, EGR2 and TGFBR3. The successful maturation of the oocytes was additionally confirmed with the use of lipid droplet assay. The genes were briefly described and related to the literature sources, to investigate their potential roles in the process of oocyte maturation. The results of the study may serve as a basic molecular reference for further research aimed at improving the methods of oocyte in vitro maturation, which plays an important role in the procedures of assisted reproduction.
- Klíčová slova
- Microarray, Mitochondrial activity, Oocyte maturation, Pig,
- MeSH
- eosin chemie MeSH
- hematoxylin chemie MeSH
- hormony genetika metabolismus MeSH
- IVM techniky * MeSH
- kultivované buňky MeSH
- lipidy analýza MeSH
- oocyty růst a vývoj metabolismus MeSH
- oxaziny chemie MeSH
- prasata MeSH
- signální transdukce MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- Brilliant Cresyl Blue MeSH Prohlížeč
- eosin MeSH
- hematoxylin MeSH
- hormony MeSH
- lipidy MeSH
- oxaziny MeSH
This paper aims to identify and describe new genetic markers involved in the processes of protein expression and modification reflected in the change of mitochondrial activity before and after in vitro maturation of the oocyte. Porcine oocytes collected from the ovaries of slaughtered landrace gilts were subjected to the process of in vitro maturation. Transcriptomic changes in the expression profile of oocyte genes involved in response to hypoxia, the transmembrane protein receptor serine threonine kinase signaling pathway, the "transforming growth factor β receptor signaling pathway", "response to protein stimulus", and "response to organic substance" were investigated using microarrays. The expression values of these genes in oocytes was analyzed before (immature) and after (mature) in vitro maturation, with significant differences found. All the significantly altered genes showed downregulation after the maturation process. The most changed genes from these gene ontologies, FOS, ID2, VEGFA, BTG2, CYR61, ESR1, AR, TACR3, CCND2, CHRDL1, were chosen to be further validated, described and related to the literature. Additionally, the mitochondrial activity of the analyzed oocytes was measured using specific dyes. We found that the mitochondrial activity was higher before the maturation process. The analysis of these results and the available literature provides a novel insight on the processes that occur during in vitro oocyte maturation. While this knowledge may prove to be useful in further research of the procedures commonly associated with in vitro fertilization procedures, it serves mostly as a basic reference for further proteomic, in vivo, and clinical studies that are necessary to translate it into practical applications.
- Klíčová slova
- microarray, mitochondrial activity, oocyte maturation, pig,
- MeSH
- hypoxie buňky genetika MeSH
- IVM techniky MeSH
- kultivované buňky MeSH
- mitochondrie genetika metabolismus MeSH
- oocyty cytologie metabolismus MeSH
- oogeneze genetika MeSH
- prasata MeSH
- signální transdukce MeSH
- transformující růstový faktor beta metabolismus MeSH
- transkriptom * MeSH
- tyrosinkinasové receptory metabolismus MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- transformující růstový faktor beta MeSH
- tyrosinkinasové receptory MeSH
The growth and development of oocyte affect the functional activities of the surrounding somatic cells. These cells are regulated by various types of hormones, proteins, metabolites, and regulatory molecules through gap communication, ultimately leading to the development and maturation of oocytes. The close association between somatic cells and oocytes, which together form the cumulus-oocyte complexes (COCs), and their bi-directional communication are crucial for the acquisition of developmental competences by the oocyte. In this study, oocytes were extracted from the ovaries obtained from crossbred landrace gilts and subjected to in vitro maturation. RNA isolated from those oocytes was used for the subsequent microarray analysis. The data obtained shows, for the first time, variable levels of gene expression (fold changes higher than |2| and adjusted p-value < 0.05) belonging to four ontological groups: regulation of cell proliferation (GO:0042127), regulation of cell migration (GO:0030334), and regulation of programmed cell death (GO:0043067) that can be used together as proliferation, migration or apoptosis markers. We have identified several genes of porcine oocytes (ID2, VEGFA, BTG2, ESR1, CCND2, EDNRA, ANGPTL4, TGFBR3, GJA1, LAMA2, KIT, TPM1, VCP, GRID2, MEF2C, RPS3A, PLD1, BTG3, CD47, MITF), whose expression after in vitro maturation (IVM) is downregulated with different degrees. Our results may be helpful in further elucidating the molecular basis and functional significance of a number of gene markers associated with the processes of migration, proliferation and angiogenesis occurring in COCs.
- Klíčová slova
- cellular competence, microarray, oocytes, pig,
- MeSH
- apoptóza genetika MeSH
- down regulace MeSH
- genové regulační sítě MeSH
- IVM techniky MeSH
- kumulární buňky metabolismus patologie MeSH
- oocyty růst a vývoj metabolismus patologie MeSH
- pohyb buněk genetika MeSH
- prasata MeSH
- proliferace buněk genetika MeSH
- RNA genetika metabolismus MeSH
- sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
- stanovení celkové genové exprese MeSH
- transkriptom * MeSH
- upregulace MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- RNA MeSH
The regulation of gene transcription allows yeast cells to respond properly to changing environmental conditions. Several protein complexes take part in this process. They involve RNA polymerase complexes, chromatin remodeling complexes, mediators, general transcription factors and specific transcriptional regulators. Using Saccharomyces cerevisiae as reference, the genomes of six species (Ashbya gossypii, Kluyveromyces lactis, K. waltii, Candida albicans, C. glabrata and Schizosaccharomyces pombe) that are human pathogens or important for the food industry were analyzed for their complement of genes encoding the homologous transcriptional regulators. The number of orthologs identified in a given species correlated with its phylogenetic distance from S. cerevisiae. Many duplicated genes encoding transcriptional regulators in S. cerevisiae and C. glabrata were reduced to one copy in species diverged before the ancestral whole genome duplication. Some transcriptional regulators appear to be specific for S. cerevisiae and probably reflect the physiological differences among species. Phylogenetic analysis and conserved gene order relationships indicate that a similar set of gene families involved in the control of multidrug resistance and oxidative stress response already existed in the common ancestor of the compared fungal species.
- MeSH
- fungální léková rezistence MeSH
- fungální proteiny chemie genetika metabolismus MeSH
- fylogeneze MeSH
- genetická transkripce * MeSH
- genom fungální * MeSH
- kvasinky chemie klasifikace genetika metabolismus MeSH
- molekulární sekvence - údaje MeSH
- regulace genové exprese u hub MeSH
- sekvence aminokyselin MeSH
- transkripční faktory chemie genetika metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- srovnávací studie MeSH
- Názvy látek
- fungální proteiny MeSH
- transkripční faktory MeSH