Research groups

We are interested in the study of the molecular mechanisms used by plants to modulate their processes of growth and environmental adaptation. We use multidisciplinar approaches such as genetics, biochemistry, physiology, molecular and celular biology with the model plant Arabidopsis thaliana.

Among the plant growth regulators we study the polyamines, molecules that derive from amino acid catabolism and play relevant roles in plant biology. These small aliphatic compounds behave as polications at physiological pH and perform essential functions with unknown molecular mechanisms.

RESEARCH LINES: Our current efforts aim to understand the molecular mechanisms of polyamine action. Several lines of research are carried out in the lab:

- Polyamines and translation. This action aims to the characterization of an exclusive post-translational modification, mediated by the spermidine, of the essential translation factor eIF5A (hypusination). This translation factor, activated by hypusination, is highly conserved among eukaryotes and it has been involved in cell growth, death and autophagy pathways. eIF5A performs diverse actions at the post-transcriptional level (mRNA binding, transport and translation), however its mRNA targets and specific functions remain ill-defined in plants.

Another polyamine that attracts our interest as being involved in translational regulation is the thermospermine, a plant specific polyamine present also in some prokaryotes but absent in animals and fungi. Thermospermine is required for the translation of atypical bHLH factors that present upstream open reading frames (uORFs) in their 5’-leader sequences and are involved in xylem development, although the molecular mechanism is unknown.

- Polyamines and pollen thermotolerance. With this project we want to elucidate the functions of polyamines in pollen germination and pollen tube growth at high temperature. We use the Riboseq technology to identify the translatome features (mRNA sequences translated by ribosomes) of the pollen tube grown in vitro at high temperature conditions. We also study the cross-talk between polyamines and pH on pollen thermotolerance.

- Polyamines and autophagy. This is a recently initiated research line that will be the focus of our future goals. The involvement of spermidine and eIF5A in longevity through the activation of the autophagy process is well documented in animals. However, there is no information with regard to equivalent functions in plants. Our interest is the characterization of the roles of polyamines in the autophagy process in response to nutritional starvation, with the aim to identify new biotechnological targets to improve nitrogen use efficiency and to reduce the use of plant fertilizers.

TECHNOLOGICAL PLATFORMS. To perform the above summarized research lines, we have implemented technologies for protein-protein interactions studies (BiFC) and also for high resolution studies of translation (Ribo-Seq):

- Protein interaction studies by BiFC. We have designed and developed our own binary vectors (http://www.ibmcp.upv.es/FerrandoLabVectors) that facilitate the generation of translational fusions to fluorescent proteins. This set of vectors allow the visualization of protein interactions in vivo in plant cells by means of Bi-molecular-Fluorescence Complementation (BiFC).

- Studies of the translatome by ribosome footprint profiling (Ribo-Seq). We have implemented the advanced technology of Ribo-Seq that allows the global studies of mRNA translation at the sub-codon resolution level, by massive sequencing of ribosome protected mRNA fragments.