S6KdiurnalgrowthArab · Integrating cell growth and cell division with light signals and circadian clock function – the role of Arabidopsis S6 kinase in the regulation of the diurnal pattern of growth
7РП — „Хора“ (Действия „Мария Кюри“)
- Период
- 2013-03-01 → 2017-02-28
- Финансиране от ЕС
- 100 000 €
- Участници
- 1
- Схема
- MC-CIG
Линиите свързват координатора с партньорите.
Накратко на български
Протеинът S6 kinase при растението Arabidopsis се изследва като механизъм, който свързва светлинните сигнали и вътрешния биологичен часовник с растежа на клетките. Това помага да се разбере как растенията регулират развитието и биомасата си спрямо околната среда.
Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.
Резултати накратко
Integrating cell growth and cell division with light signals and circadian clock function – the role of Arabidopsis S6 kinase in the regulation of the diurnal pattern of growth
The 40S ribosomal protein S6 kinase (S6K) is an evolutionary conserved component of the TOR growth signalling pathway in eukaryotes. S6K functions as a regulator of protein synthesis due to its ability to promote mRNA translation through the direct phosphorylation of the ribosomal protein S6 in a TOR-dependent manner. Arabidopsis thaliana S6K is regulated by nutrient availability, osmotic stress, phytohormone signalling (e.g. auxin) as well as light and sugar. S6K is encoded by two genes, S6K1 and S6K2, organized in close proximity in chromosome 3. We have previously shown that S6K associates with the E2FB/RBR1 pathway to inhibit cell proliferation, an indication that S6K could constitute a molecular switch between cell growth and proliferation. Interestingly, S6K1 is co-expressed with CCA1 (CIRCADIAN CLOCK ASSOCIATED 1), a crucial component of the circadian clock core oscillator. This finding suggests that S6K transcription could be regulated by the clock. The circadian clock is an internal timekeeping mechanism allowing plants to adjust fundamental biological processes to environmental conditions. The combined action of light perception and the clock constitutes a coincidence mechanism regulating the diurnal pattern of growth especially in young seedlings. In addition the circadian clock is paramount in the regulation of plant fitness and biomass. However, very little is known on the downstream circadian-regulated outputs that account for these extremely relevant functions. Therefore, in this project we investigated the circadian regulation of Arabidopsis S6K1 and S6K2 both at the transcriptional, translational and post-translational levels. We monitored S6K1 and S6K2 expression patterns in different plant organs with specific developmental programs, focusing specially in hypocotyls, cotyledons and roots. In addition, we did a comprehensive analysis of light, circadian and growth-related phenotypes associated either with depletion or increase of S6K levels. We propose that the circadian clock provides additional transcriptional and post-translational regulation of S6Ks. This regulation is integrated with organ-specific responses, suggesting that S6K protein function could be adjusted to specific plant developmental programs. Taken together our results identify and characterize new circadian-regulated outputs. They widen our understanding of the molecular mechanisms underlying circadian clock function in plants and their relevance in adjusting plant growth responses to environmental conditions.
Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз
Цел на проекта
Light and the circadian clock control the timing of growth and neighbor sensing and are critical for proper regulation of fitness and biomass. At the intersection of these two pathways are the PIF transcription factors. However, although the components of both pathways are known, their downstream effectors are still poorly understood. In this proposal I plan to establish a functional connection between environmental perception and the molecular mechanisms controlling cell growth and proliferation, by looking at downstream outputs of light and the clock. I have previously shown that the growth-signalling regulator Arabidopsis 40S ribosomal protein S6 Kinase1 (S6K1) is also a inhibitor of cell division due to its ability to form a complex with RBR1 and E2FB. I found that S6K1 is co-expressed with CCA1, a major clock component and my preliminary data suggest that PIF and other circadian regulators could control S6K1 expression. I plan to confirm those observations and characterize the light and circadian regulation of S6K1 and also S6K2 both at transcriptional and post-translational levels. Moreover, I plan to extend this analysis to RBR1-E2FB and other regulators of cell growth and cell division. These findings will provide a better understanding of how cell growth and cell cycle regulation are connected and how the environment affects both. Furthermore, the characterization of these downstream regulators and their mode of action could allow the manipulation of plant yield under sub-optimal field conditions, and this knowledge could be transferred to other species with economic and agricultural importance.
Оригинален текст от CORDIS (на английски).
Участници
- CENTRE DE RECERCA EN AGRIGENOMICA CSIC-IRTA-UAB-UB · CERDANYOLA DEL VALLESКоординаторИспания
Връзки
Данни: CORDIS, © Европейски съюз