Over millions of years of evolution, plants have developed the ability to perceive and integrate all the information coming from external signals with their internal development and growth programs to always produce appropriate responses. It is increasingly evident that plant hormones play a central role in this integration process. Our group has developed two independent research lines analyzing the effects on gene expression regulation triggered by the plant hormones ethylene and auxin. We are trying to determine key molecular mechanisms involved in the integration process of environmental cues with the plant endogenous programs, and mediated by these plant hormones.
Regulation of translation in tomato fruit ripening.
Ethylene is a plant hormone involved in many plant developmental processes. It is essential in the ripening and softening of agricultural products and, therefore, is one of the main determinants of quality and shelf life of fruits and vegetables. A better understanding of the molecular mechanisms of how ethylene regulates fruit ripening can have direct applications in the agronomic sector.
In the last decades, we have studied this regulation mainly at the transcriptional level, first using microarrays and then RNA-seq. While other levels of regulation, such as changes in the efficiency of translation, have barely been explored. In our laboratory, we have implemented a novel technique -Ribosome footprinting or Ribo-seq- to identify regulated messenger RNAs at the translational level. Our preliminary results suggest that the translation of certain messenger RNAs is under firm regulation during fruit ripening.
Our goal is to unravel how ethylene regulates translation, as opposed to transcription, of particular mRNAs during tomato ripening, a process tightly regulated by ethylene, and to confirm the universality or conservation in the plant kingdom of essential elements that mediate regulation of translation in response to ethylene.
Regulation of local auxin production.
Auxin is a key plant hormone that regulates plant development and coordinates plant responses to the environment. Auxin morphogenic gradients control cell fate destiny and provides plant phenotypic plasticity. Polar auxin transport is key for the generation and maintenance of the auxin gradients. The recent discovery of the refined spatiotemporal expression patterns of auxin biosynthesis genes suggests that local auxin production also contributes to the formation of the auxin maxima.
Our research focuses on the regulation of local auxin production and the physiological consequences of altering the dynamic spatiotemporal patterns of auxin biosynthesis. We have developed molecular tools to modify the specific patterns of auxin production with high precision to define the roles of local auxin biosynthesis in different plant developmental processes and responses to environmental stimuli.
