De-etiolation is the first developmental process under light control allowing the heterotrophic seedling to become autotrophic. The phytohormones cytokinins (CKs) largely contribute to this process. Reversible phosphorylation is a key event of cell signaling, allowing proteins to become active or generating a binding site for specific protein interaction. 14-3-3 proteins regulate a variety of plant responses. The expression, hormonal regulation, and proteomic network under the control of 14-3-3s were addressed in tomato (Solanum lycopersicum L.) during blue light-induced photomorphogenesis. Two isoforms were specifically investigated due to their high expression during tomato de-etiolation. The multidisciplinary approach demonstrated that TFT9 expression, but not TFT6, was regulated by CKs and identified cis-regulating elements required for this response. Our study revealed >130 potential TFT6/9 interactors. Their functional annotation predicted that TFTs might regulate the activity of proteins involved notably in cell wall strengthening or primary metabolism. Several potential interactors were also predicted to be CK-responsive. For the first time, the 14-3-3 interactome linked to de-etiolation was investigated and evidenced that 14-3-3s might be involved in CK signaling pathway, cell expansion inhibition and steady-state growth rate establishment, and reprograming from heterotrophy to autotrophy. BIOLOGICAL SIGNIFICANCE: Tomato (Solanum lycopersicum L.) is one of the most important vegetables consumed all around the world and represents probably the most preferred garden crop. Regulation of hypocotyl growth by light plays an important role in the early development of a seedling, and consequently the homogeneity of the culture. The present study focuses on the importance of tomato 14-3-3/TFT proteins in this process. We provide here the first report of 14-3-3 interactome in the regulation of light-induced de-etiolation and subsequent photomorphogenesis. Our data provide new insights into light-induced de-etiolation and open new horizons for dissecting the post-transcriptional regulations.
- MeSH
- chromatografie afinitní MeSH
- mapy interakcí proteinů * MeSH
- proteiny 14-3-3 metabolismus MeSH
- proteomika * MeSH
- rostlinné proteiny metabolismus MeSH
- semenáček růst a vývoj MeSH
- Solanum lycopersicum růst a vývoj MeSH
- světlo * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Recent technological advances have made next-generation sequencing (NGS) a popular and financially accessible technique allowing a broad range of analyses to be done simultaneously. A huge amount of newly generated NGS data, however, require advanced software support to help both in analyzing the data and biologically interpreting the results. In this article, we describe SATrans (Software for Annotation of Transcriptome), a software package providing fast and robust functional annotation of novel sequences obtained from transcriptome sequencing. Moreover, it performs advanced gene ontology analysis of differentially expressed genes, thereby helping to interpret biologically-and in a user-friendly form-the quantitative changes in gene expression. The software is freely available and provides the possibility to work with thousands of sequences using a standard personal computer or notebook running on the Linux operating system.
Physiologically, abscisic acid (ABA) is believed to be a general inhibitor of plant growth, including during the crucial early development of seedlings. However, this view contradicts many reports of stimulatory effects of ABA that, so far, have not been considered in the debate concerning ABA's function in plant development. To address this apparent contradiction, we propose a hypothetical mechanism to explain how ABA might contribute to the promotion of cell expansion. We wish to overturn conventional views on ABA's role during juvenile plant development and put forward the idea that, as for other phytohormones, the role of ABA is determined by dose and sensitivity and ranges from stimulatory to inhibitory effects.
BACKGROUND: De-etiolation is the switch from skoto- to photomorphogenesis, enabling the heterotrophic etiolated seedling to develop into an autotrophic plant. Upon exposure to blue light (BL), reduction of hypocotyl growth rate occurs in two phases: a rapid inhibition mediated by phototropin 1 (PHOT1) within the first 30-40 min of illumination, followed by the cryptochrome 1 (CRY1)-controlled establishment of the steady-state growth rate. Although some information is available for CRY1-mediated de-etiolation, less attention has been given to the PHOT1 phase of de-etiolation. RESULTS: We generated a subtracted cDNA library using the suppression subtractive hybridization method to investigate the molecular mechanisms of BL-induced de-etiolation in tomato (Solanum lycopersicum L.), an economically important crop. We focused our interest on the first 30 min following the exposure to BL when PHOT1 is required to induce the process. Our library generated 152 expressed sequence tags that were found to be rapidly accumulated upon exposure to BL and consequently potentially regulated by PHOT1. Annotation revealed that biological functions such as modification of chromatin structure, cell wall modification, and transcription/translation comprise an important part of events contributing to the establishment of photomorphogenesis in young tomato seedlings. Our conclusions based on bioinformatics data were supported by qRT-PCR analyses the specific investigation of V-H(+)-ATPase during de-etiolation in tomato. CONCLUSIONS: Our study provides the first report dealing with understanding the PHOT1-mediated phase of de-etiolation. Using subtractive cDNA library, we were able to identify important regulatory mechanisms. The profound induction of transcription/translation, as well as modification of chromatin structure, is relevant in regard to the fact that the entry into photomorphogenesis is based on a deep reprograming of the cell. Also, we postulated that BL restrains the cell expansion by the rapid modification of the cell wall.
- MeSH
- chromatin ultrastruktura MeSH
- etiolizace genetika MeSH
- fototropiny fyziologie MeSH
- genová knihovna MeSH
- genové regulační sítě MeSH
- hypokotyl růst a vývoj MeSH
- regulace genové exprese u rostlin MeSH
- semenáček genetika růst a vývoj MeSH
- Solanum lycopersicum genetika růst a vývoj MeSH
- světlo * MeSH
- upregulace MeSH
- vakuolární protonové ATPasy genetika fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cytokinin plant hormones have been shown to play an important role in plant response to abiotic stresses. Herein, we expand upon the findings of Pospíšilová et al. [30] regarding preparation of novel transgenic barley lines overexpressing cytokinin dehydrogenase 1 gene from Arabidopsis under the control of mild root-specific promotor of maize β-glycosidase. These lines showed drought-tolerant phenotype mainly due to alteration of root architecture and stronger lignification of root tissue. A detailed transcriptomic analysis of roots of transgenic plants subjected to revitalization after drought stress revealed attenuated response through the HvHK3 cytokinin receptor and up-regulation of two transcription factors implicated in stress responses and abscisic acid sensitivity. Increased expression of several genes involved in the phenylpropanoid pathway as well as of genes encoding arogenate dehydratase/lyase participating in phenylalanine synthesis was found in roots during revitalization. Although more precursors of lignin synthesis were present in roots after drought stress, final lignin accumulation did not change compared to that in plants grown under optimal conditions. Changes in transcriptome indicated a higher auxin turnover in transgenic roots. The same analysis in leaves revealed that genes encoding putative enzymes responsible for production of jasmonates and other volatile compounds were up-regulated. Although transgenic barley leaves showed lower chlorophyll content and down-regulation of genes encoding proteins involved in photosynthesis than did wild-type plants when cultivated under optimal conditions, they did show a tendency to return to initial photochemical activities faster than did wild-type leaves when re-watered after severe drought stress. In contrast to optimal conditions, comparative transcriptomic analysis of revitalized leaves displayed up-regulation of genes encoding enzymes and proteins involved in photosynthesis, and especially those encoded by the chloroplast genome. Taken together, our results indicate that the partial cytokinin insensitivity induced in barley overexpressing cytokinin dehydrogenase contributes to tolerance to drought stress.
- MeSH
- aklimatizace genetika fyziologie MeSH
- biotechnologie MeSH
- cytokininy metabolismus MeSH
- fotosyntéza MeSH
- fyziologický stres MeSH
- geneticky modifikované rostliny MeSH
- homeostáza MeSH
- ječmen (rod) genetika fyziologie MeSH
- kořeny rostlin genetika metabolismus MeSH
- období sucha MeSH
- oxidoreduktasy genetika metabolismus MeSH
- proteiny huseníčku genetika metabolismus MeSH
- regulátory růstu rostlin metabolismus MeSH
- rostlinné geny MeSH
- rostlinné proteiny genetika metabolismus MeSH
- stanovení celkové genové exprese MeSH
- Publikační typ
- časopisecké články MeSH
Together with auxins, cytokinins are the main plant hormones involved in many different physiological processes. Given this knowledge, cytokinin levels can be manipulated by genetic modification in order to improve agronomic parameters of cereals in relation to, for example, morphology, yield, and tolerance to various stresses. The barley (Hordeum vulgare) cultivar Golden Promise was transformed using the cytokinin dehydrogenase 1 gene from Arabidopsis thaliana (AtCKX1) under the control of mild root-specific β-glucosidase promoter from maize. Increased cytokinin degradation activity was observed positively to affect the number and length of lateral roots. The impact on morphology depended upon the recombinant protein's subcellular compartmentation. While assumed cytosolic and vacuolar targeting of AtCKX1 had negligible effect on shoot growth, secretion of AtCKX1 protein to the apoplast had a negative effect on development of the aerial part and yield. Upon the application of severe drought stress, all transgenic genotypes maintained higher water content and showed better growth and yield parameters during revitalization. Higher tolerance to drought stress was most caused by altered root morphology resulting in better dehydration avoidance.
- MeSH
- aklimatizace genetika fyziologie MeSH
- biotechnologie MeSH
- cytokininy genetika metabolismus MeSH
- fenotyp MeSH
- fyziologický stres MeSH
- geneticky modifikované rostliny MeSH
- ječmen (rod) genetika růst a vývoj fyziologie MeSH
- kořeny rostlin fyziologie MeSH
- metabolické sítě a dráhy MeSH
- období sucha MeSH
- oxidoreduktasy genetika MeSH
- proteiny huseníčku genetika fyziologie MeSH
- regulátory růstu rostlin genetika metabolismus MeSH
- rekombinantní proteiny genetika metabolismus MeSH
- rostlinné geny MeSH
- rostlinné proteiny genetika MeSH
- stanovení celkové genové exprese MeSH
- upregulace MeSH
- Publikační typ
- časopisecké články MeSH
The role of abscisic acid (ABA) during early development was investigated in tomato seedlings. The endogenous content of ABA in particular organs was analyzed in seedlings grown in the dark and under blue light. Our results showed that in dark-grown seedlings, the ABA accumulation was maximal in the cotyledons and elongation zone of hypocotyl, whereas under blue-light, the ABA content was distinctly reduced. Our data are consistent with the conclusion that ABA promotes the growth of etiolated seedlings and the results suggest that ABA plays an inhibitory role in de-etiolation and photomorphogenesis in tomato.
Dark-induced growth (skotomorphogenesis) is primarily characterized by rapid elongation of the hypocotyl. We have studied the role of abscisic acid (ABA) during the development of young tomato (Solanum lycopersicum L.) seedlings. We observed that ABA deficiency caused a reduction in hypocotyl growth at the level of cell elongation and that the growth in ABA-deficient plants could be improved by treatment with exogenous ABA, through which the plants show a concentration dependent response. In addition, ABA accumulated in dark-grown tomato seedlings that grew rapidly, whereas seedlings grown under blue light exhibited low growth rates and accumulated less ABA. We demonstrated that ABA promotes DNA endoreduplication by enhancing the expression of the genes encoding inhibitors of cyclin-dependent kinases SlKRP1 and SlKRP3 and by reducing cytokinin levels. These data were supported by the expression analysis of the genes which encode enzymes involved in ABA and CK metabolism. Our results show that ABA is essential for the process of hypocotyl elongation and that appropriate control of the endogenous level of ABA is required in order to drive the growth of etiolated seedlings.
- MeSH
- cyklin-dependentní kinasy antagonisté a inhibitory MeSH
- cytokininy biosyntéza metabolismus MeSH
- endoreduplikace účinky záření MeSH
- homeostáza účinky záření MeSH
- hypokotyl cytologie růst a vývoj metabolismus účinky záření MeSH
- inhibitory proteinkinas farmakologie MeSH
- klíčení účinky léků účinky záření MeSH
- kyselina abscisová metabolismus MeSH
- Solanum lycopersicum cytologie růst a vývoj metabolismus účinky záření MeSH
- tma * MeSH
- vývoj rostlin účinky léků účinky záření MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Imported from the Andean region to Europe in the 16th century, today tomato is widespread throughout the world and represents the most economically important vegetable crop worldwide. Tomato is not only traded in the fresh market but is also used in the processing industry in soups, as paste, concentrate, juice, and ketchup. It is an incredible source of important nutrients such as lycopene, β-carotene and vitamin C, which all have positive impacts on human health. Its production and consumption is increasing with population growth. In this review, we report how tomato was already domesticated by the ancient Incan and Aztec civilizations, and how it came to Europe, where its breeding history started. The development of genetic, molecular biology and plant biotechnology have opened the doors towards the modern genetic engineering of tomato. The different goals of tomato genetic engineering are presented, as well as examples of successfully engineered tomatoes in terms of resistance to biotic and abiotic stresses, and fruit quality. The development of GM tomato for biopharming is also described.
- MeSH
- biotechnologie * MeSH
- dějiny 16. století MeSH
- dějiny 18. století MeSH
- dějiny 19. století MeSH
- dějiny 20. století MeSH
- dějiny 21. století MeSH
- genetické inženýrství MeSH
- geneticky modifikované rostliny * MeSH
- ovoce * MeSH
- Solanum lycopersicum dějiny MeSH
- zemědělské plodiny * MeSH
- Check Tag
- dějiny 16. století MeSH
- dějiny 18. století MeSH
- dějiny 19. století MeSH
- dějiny 20. století MeSH
- dějiny 21. století MeSH
- Publikační typ
- časopisecké články MeSH
- historické články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Light is one of the most important factor influencing plant growth and development all through their life cycle. One of the well-known light-regulated processes is de-etiolation, i.e. the switch from skotomorphogenesis to photomorphogenesis. The hormones cytokinins (CKs) play an important role during the establishment of photomorphogenesis as exogenous CKs induced photomorphogenesis of dark-grown seedlings. Most of the studies are conducted on the plant model Arabidopsis, but no or few information are available for important crop species, such as tomato (Solanum lycopersicum L.). In our study, we analyzed for the first time the endogenous CKs content in tomato hypocotyls during skotomorphogenesis, photomorphogenesis and de-etiolation. For this purpose, two tomato genotypes were used: cv. Rutgers (wild-type; WT) and its corresponding mutant (7B-1) affected in its responses to blue light (BL). Using physiological and molecular approaches, we identified that the skotomorphogenesis is characterized by an endoreduplication-mediated cell expansion, which is inhibited upon BL exposure as seen by the accumulation of trancripts encoding CycD3, key regulators of the cell cycle. Our study showed for the first time that iP (isopentenyladenine) is the CK accumulated in the tomato hypocotyl upon BL exposure, suggesting its specific role in photomorphogenesis. This result was supported by physiological experiments and gene expression data. We propose a common model to explain the role and the relationship between CKs, namely iP, and endoreduplication during de-etiolation and photomorphogenesis.
- MeSH
- buněčný cyklus účinky léků genetika MeSH
- cyklin D3 genetika metabolismus MeSH
- cytokininy metabolismus MeSH
- endoreduplikace fyziologie účinky záření MeSH
- fylogeneze MeSH
- hypokotyl fyziologie účinky záření MeSH
- isopentenyladenosin metabolismus MeSH
- morfogeneze fyziologie účinky záření MeSH
- ploidie MeSH
- rostlinné proteiny genetika metabolismus MeSH
- semenáček fyziologie účinky záření MeSH
- Solanum lycopersicum fyziologie účinky záření MeSH
- světlo MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
