Regulatory Mechanisms in Dark/Light Growth and Development

Group Structure

Group Leader: Elena Monte (CSIC Assistant Professor)
Career Track Fellows: Céline Natacha Díaz, Pablo Leivar
PhD Students: Maria Sentandreu (until January 2013), Judit Soy, Guiomar Martín, Arnau Rovira (since February 2013).
Undergrad or Master Students: Roger Miralles (2012), Bernat Miró (summer 2012), Marcel Uson (Summer 2013).

Summary

Plants need light not only for photosynthesis but also as a source of vital information about their environment. Accurate reading of the signals provided by light (quantity, direction, color, and duration) informs plants throughout their life cycle about their germination environment, the time of day, and the onset of the seasons. We are particularly interested in the transitions between dark and light as they represent a major challenge for plant adaptation. In response to these light changes that occur after germination or during the daily cycles, plants reprogram their growth, developmental pattern, and metabolism to ensure fitness and survival. During 2012-2013, our laboratory has focused on understanding the regulatory networks and mechanisms underlying the plant perception and response to dark/light transitions. We have found that the phytochrome photoreceptors impose oscillations in the abundance of the transcription factor PIF3, which accumulates and induces growth specifically at the end of the night. Our laboratory has also identified targets of this phytochrome/PIF regulatory module that have organ-specific roles during the dramatic developmental switch that takes place when the seedling reaches the soil surface after germination in the underground darkness. These findings have allowed us to advance in our aim to understand how plants thrive in a dynamic light environment.

Research Projects

  • Definition of Dark/Light-regulated transcriptional networks
  • Dynamics of phytochrome photoreceptor regulation of transcription factor accumulation
  • Mechanism of action of Phytochrome-Interacting bHLH transcription factors PIFs as plant growth regulators
  • Identification and characterization of PIF-regulated MIDAs as organ-specific growth regulators in Dark/Light development

Selected Publications

Soy J., Leivar P., Gonzalez-Schain N., Sentandreu M., Prat S., Quail P.H., Monte E.
Phytochrome-imposed oscillations in PIF3 protein abundance regulate hypocotyl growth under diurnal light/dark conditions in Arabidopsis
(2012) Plant Journal, vol. 71 (3), pp. 390-401

Sentandreu M., Leivar P., Martin G., Monte E.
Branching of the PIF3 regulatory network in Arabidopsis: Roles of PIF3-regulated MIDAs in seedling development in the dark and in response to light
(2012) Plant Signaling and Behavior, vol. 7 (4), pp. 510-513

Leivar P., Tepperman J.M., Cohn M.M., Monte E., Al-Sady B., Erickson E., Quail P.H.
Dynamic antagonism between phytochromes and PIF family basic helix-loop-helix factors induces selective reciprocal responses to light and shade in a rapidly responsive transcriptional network in Arabidopsis
(2012) Plant Cell, vol. 24 (4), pp. 1398-1419

Leivar P., Monte E., Cohn M.M., Quail P.H.
Phytochrome signaling in green Arabidopsis seedlings: Impact assessment of a mutually negative phyB-PIF feedback loop
(2012) Molecular Plant, vol. 5 (3), pp. 734-749

Adam E., Kircher S., Liu P., Merai Z., Gonzalez-Schain N., Horner M., Viczian A., Monte E., Sharrock R.A., Schafer E., Nagy F.
Comparative functional analysis of full-length and N-terminal fragments of phytochrome C, D and E in red light-induced signaling
(2013) New Phytologist, vol. 200 (1), pp. 86-96