Translationally controlled tumor protein (TCTP) is a multifunctional and highly conserved protein from yeast to humans. Recently, its role in non-selective autophagy has been reported with controversial results in mammalian and human cells. Herein we examine the effect of Mmi1, the yeast ortholog of TCTP, on non-selective autophagy in budding yeast Saccharomyces cerevisiae, a well-established model system to monitor autophagy. We induced autophagy by nitrogen starvation or rapamycin addition and measured autophagy by using the Pho8Δ60 and GFP-Atg8 processing assays in WT, mmi1Δ, and in autophagy-deficient strains atg8Δ or atg1Δ. Our results demonstrate that Mmi1 does not affect basal or nitrogen starvation-induced autophagy. However, an increased rapamycin-induced autophagy is detected in mmi1Δ strain when the cells enter the post-diauxic growth phase, and this phenotype can be rescued by inserted wild-type MMI1 gene. Further, the mmi1Δ cells exhibit significantly lower amounts of reactive oxygen species (ROS) in the post-diauxic growth phase compared to WT cells. In summary, our study suggests that Mmi1 negatively affects rapamycin-induced autophagy in the post-diauxic growth phase and supports the role of Mmi1/TCTP as a negative autophagy regulator in eukaryotic cells.

• Klíčová slova
• Mmi1, TCTP, autophagy, nitrogen starvation, rapamycin, reactive oxygen species, translationally controlled tumor protein,
• MeSH
• autofagie * účinky léků   MeSH
• dusík nedostatek   MeSH
• glukosa farmakologie   MeSH
• mutace genetika   MeSH
• nádorové biomarkery chemie   MeSH
• proteiny vázající vápník metabolismus   MeSH
• Saccharomyces cerevisiae - proteiny metabolismus   MeSH
• Saccharomyces cerevisiae cytologie   účinky léků   růst a vývoj   MeSH
• sirolimus farmakologie   MeSH
• superoxidy metabolismus   MeSH
• translačně kontrolovaný nádorový protein 1 MeSH
• zelené fluorescenční proteiny metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• dusík MeSH
• glukosa MeSH
• nádorové biomarkery MeSH
• proteiny vázající vápník MeSH
• Saccharomyces cerevisiae - proteiny MeSH
• sirolimus MeSH
• superoxidy MeSH
• TMA19 protein, S cerevisiae MeSH Prohlížeč
• TPT1 protein, human MeSH Prohlížeč
• translačně kontrolovaný nádorový protein 1 MeSH
• zelené fluorescenční proteiny MeSH

The membrane-embedded FtsH proteases found in bacteria, chloroplasts, and mitochondria are involved in diverse cellular processes including protein quality control and regulation. The genome of the model cyanobacterium Synechocystis sp PCC 6803 encodes four FtsH homologs designated FtsH1 to FtsH4. The FtsH3 homolog is present in two hetero-oligomeric complexes: FtsH2/3, which is responsible for photosystem II quality control, and the essential FtsH1/3 complex, which helps maintain Fe homeostasis by regulating the level of the transcription factor Fur. To gain a more comprehensive insight into the physiological roles of FtsH hetero-complexes, we performed genome-wide expression profiling and global proteomic analyses of Synechocystis mutants conditionally depleted of FtsH3 or FtsH1 grown under various nutrient conditions. We show that the lack of FtsH1/3 leads to a drastic reduction in the transcriptional response to nutrient stress of not only Fur but also the Pho, NdhR, and NtcA regulons. In addition, this effect is accompanied by the accumulation of the respective transcription factors. Thus, the FtsH1/3 complex is of critical importance for acclimation to iron, phosphate, carbon, and nitrogen starvation in Synechocystis.plantcell;31/12/2912/FX1F1fx1.

• MeSH
• aklimatizace genetika   MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• dusík nedostatek   metabolismus   MeSH
• exprese genu MeSH
• fosfáty nedostatek   metabolismus   MeSH
• fosforylace MeSH
• fotosystém II - proteinový komplex chemie   genetika   metabolismus   MeSH
• metaloproteasy genetika   metabolismus   MeSH
• mutace MeSH
• proteiny vázající fosfáty genetika   metabolismus   MeSH
• proteolýza MeSH
• proteom genetika   metabolismus   MeSH
• proteomika MeSH
• regulace genové exprese u bakterií genetika   MeSH
• regulon genetika   MeSH
• represorové proteiny genetika   metabolismus   MeSH
• ribozomální proteiny genetika   metabolismus   MeSH
• Synechocystis enzymologie   metabolismus   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• uhlík nedostatek   metabolismus   MeSH
• živiny nedostatek   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální proteiny MeSH
• dusík MeSH
• ferric uptake regulating proteins, bacterial MeSH Prohlížeč
• fosfáty MeSH
• fotosystém II - proteinový komplex MeSH
• metaloproteasy MeSH
• proteiny vázající fosfáty MeSH
• proteom MeSH
• represorové proteiny MeSH
• ribozomální proteiny MeSH
• transkripční faktory MeSH
• uhlík MeSH

Arabidopsis (Arabidopsis thaliana) leaf development relies on subsequent phases of cell proliferation and cell expansion. During the proliferation phase, chloroplasts need to divide extensively, and during the transition from cell proliferation to expansion, they differentiate into photosynthetically active chloroplasts, providing the plant with energy. The transcription factor GROWTH REGULATING FACTOR5 (GRF5) promotes the duration of the cell proliferation period during leaf development. Here, it is shown that GRF5 also stimulates chloroplast division, resulting in a higher chloroplast number per cell with a concomitant increase in chlorophyll levels in 35S:GRF5 leaves, which can sustain higher rates of photosynthesis. Moreover, 35S:GRF5 plants show delayed leaf senescence and are more tolerant for growth on nitrogen-depleted medium. Cytokinins also stimulate leaf growth in part by extending the cell proliferation phase, simultaneously delaying the onset of the cell expansion phase. In addition, cytokinins are known to be involved in chloroplast development, nitrogen signaling, and senescence. Evidence is provided that GRF5 and cytokinins synergistically enhance cell division and chlorophyll retention after dark-induced senescence, which suggests that they also cooperate to stimulate chloroplast division and nitrogen assimilation. Taken together with the increased leaf size, ectopic expression of GRF5 has great potential to improve plant productivity.

• MeSH
• Arabidopsis účinky léků   genetika   fyziologie   MeSH
• buněčné dělení účinky léků   MeSH
• chlorofyl metabolismus   MeSH
• chloroplasty účinky léků   metabolismus   ultrastruktura   MeSH
• cytokininy farmakologie   MeSH
• dusík nedostatek   MeSH
• fotosyntéza * účinky léků   MeSH
• geneticky modifikované rostliny MeSH
• listy rostlin účinky léků   růst a vývoj   fyziologie   ultrastruktura   MeSH
• proteiny 14-3-3 genetika   metabolismus   MeSH
• regulace genové exprese u rostlin účinky léků   MeSH
• rostlinné geny MeSH
• trans-aktivátory genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chlorofyl MeSH
• cytokininy MeSH
• dusík MeSH
• GRF5 protein, Arabidopsis MeSH Prohlížeč
• proteiny 14-3-3 MeSH
• trans-aktivátory MeSH

Changes of photosynthetic activity in vivo of individual heterocysts and vegetative cells in the diazotrophic cyanobacterium Anabaena sp. strain PCC 7120 during the course of diazotrophic acclimation were determined using fluorescence kinetic microscopy (FKM). Distinct phases of stress and acclimation following nitrogen step-down were observed. The first was a period of perception, in which the cells used their internally stored nitrogen without detectable loss of PS II activity or pigments. In the second, the stress phase of nitrogen limitation, the cell differentiation occurred and an abrupt decline of fluorescence yield was observed. This decline in fluorescence was not paralleled by a corresponding decline in photosynthetic pigment content and PS II activity. Both maximal quantum yield and sustained electron flow were not altered in vegetative cells, only in the forming heterocysts. The third, acclimation phase started first in the differentiating heterocysts with a recovery of PS II photochemical yields [Formula: see text] Afterwards, the onset of nitrogenase activity was observed, followed by the restoration of antenna pigments in the vegetative cells, but not in the heterocysts. Surprisingly, mature heterocysts were found to have an intact PS II as judged by photochemical yields, but a strongly reduced PS II-associated antenna as judged by decreased F 0. The possible importance of the functional PS II in heterocysts is discussed. Also, the FKM approach allowed to follow in vivo and evaluate the heterogeneity in photosynthetic performance among individual vegetative cells as well as heterocysts in the course of diazotrophic acclimation. Some cells along the filament (so-called "superbright cells") were observed to display transiently increased fluorescence yield, which apparently proceeded by apoptosis.

• MeSH
• aklimatizace fyziologie   MeSH
• Anabaena cytologie   fyziologie   MeSH
• analýza jednotlivých buněk metody   MeSH
• biologické pigmenty metabolismus   MeSH
• chlorofyl metabolismus   MeSH
• dusík nedostatek   MeSH
• fluorescenční mikroskopie metody   MeSH
• fotosyntéza fyziologie   MeSH
• fyziologický stres MeSH
• kinetika MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biologické pigmenty MeSH
• chlorofyl MeSH
• dusík MeSH

Gene expression databases, acquired by proteomics and transcriptomics, describe physiological and developmental programs at the systems level. Here we analyze proteosynthetic profiles in a bacterium undergoing defined metabolic changes. Streptomyces coelicolor cultured in a defined liquid medium displays four distinct patterns of gene expression associated with growth on glutamate, diauxic transition, and growth on maltose and ammonia that terminates by starvation for nitrogen and entry into stationary phase. Principal component and fuzzy cluster analyses of the proteome database of 935 protein spot profiles revealed principal kinetic patterns. Online linkage of the proteome database (SWICZ) to a protein-function database (KEGG) revealed limited correlations between expression profiles and metabolic pathway activities. Proteins belonging to principal metabolic pathways defined characteristic kinetic profiles correlated with the physiological state of the culture. These analyses supported the concept that metabolic flux was regulated not by individual enzymes but rather by groups of enzymes whose synthesis responded to changes in nutritional conditions. Higher-level regulation is reflected by the distribution of all kinetic profiles into only nine groups. The observation that enzymes representing principal metabolic pathways displayed their own distinctive average kinetic profiles suggested that expression of a "high-flux backbone" may dominate regulation of metabolic flux.

• MeSH
• 2D gelová elektroforéza MeSH
• amoniak farmakologie   MeSH
• bakteriální proteiny biosyntéza   MeSH
• čipová analýza proteinů metody   MeSH
• dusík nedostatek   MeSH
• fyziologická adaptace MeSH
• kyselina glutamová farmakologie   MeSH
• maltosa farmakologie   MeSH
• methionin metabolismus   MeSH
• proteom MeSH
• proteosyntéza MeSH
• radioizotopy síry MeSH
• regulace genové exprese u bakterií MeSH
• signální transdukce MeSH
• sladidla farmakologie   MeSH
• Streptomyces coelicolor fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• amoniak MeSH
• bakteriální proteiny MeSH
• dusík MeSH
• kyselina glutamová MeSH
• maltosa MeSH
• methionin MeSH
• proteom MeSH
• radioizotopy síry MeSH
• sladidla MeSH

The physiology of a commercial strain of bakers' yeast was studied in terms of the cell composition under different growth conditions and of its response to stress. The study comprised fed-batch experiments since this is the system used in bakers' yeast industry. The classical fed-batch fermentation procedure was modified in that the yeast cells were continuously grown to a steady-state at a dilution rate of 0.1/h in order to achieve more or less the same initial starting point in terms of cell composition. This steady-state culture was then switched to fed-batch concomitantly with exposure to stress. The highest amount of trehalose accumulation was achieved when nutrient depletion and heat stress were applied concomitantly. The highest amount of trehalose, 12%, was attained in cells stressed by both nitrogen depletion and heat stress. The protein content remained constant, although with some oscillations, at a value of 30% throughout this dual stress experiment.

• MeSH
• biomasa MeSH
• dusík nedostatek   MeSH
• fosfáty nedostatek   MeSH
• fungální proteiny analýza   MeSH
• Saccharomyces cerevisiae fyziologie   MeSH
• vysoká teplota MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• dusík MeSH
• fosfáty MeSH
• fungální proteiny MeSH

• MeSH
• dietní proteiny aplikace a dávkování   MeSH
• draslík moč   MeSH
• dusík nedostatek   MeSH
• krmivo pro zvířata * MeSH
• močovina krev   moč   MeSH
• ovce metabolismus   MeSH
• sodík moč   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• dietní proteiny MeSH
• draslík MeSH
• dusík MeSH
• močovina MeSH
• sodík MeSH