Floral Induction and Development

Group Structure

Group Leader: Soraya Pelaz (ICREA Research Professor)
Researcher: Paula Suárez-López
Postdoctoral Researchers: Luis Matías-Hernández
PhD Students: Esther Marín-González, Andrea Elizabeth Aguilar-Jaramillo

Summary

We are interested in unraveling the mechanisms that control flowering and other developmental processes. Reproductive success is highly dependent on the moment at which plants blossom. Flowering is regulated by a complicated genetic network in response to environmental and endogenous conditions. Most plants respond to seasonal changes in day length or photoperiod. Flowering must be postponed until the plant obtains enough reserves for flower formation or reaches the appropriate time for seed set. Thus, in both inductive and non-inductive day lengths, flowering must be repressed to avoid precocious flowering. We have shown that TEMPRANILLO genes play a key role, inhibiting flowering under both conditions by repressing the florigen FT that mainly acts in inductive conditions, and the GA4 biosynthetic enzyme GA3ox1 that produces the major floral promoting factor in non-inductive day length, the gibberellins. Since TEMPRANILLO genes are conserved across land plants, we want to translate our knowledge to other plants such as poplar and rice.

We have also worked in other aspects of plant development such as tuber induction, fruit development and trichome initiation. Potato tuber induction is also regulated by photoperiod.  We have shown that the potato CONSTANS gene represses tuberization through the control of two genes that promote tuberization, StFT and StBEL5. Therefore, the CONSTANS/FT module, involved in the photoperiodic control of flowering in other species, also regulates photoperiodic tuberization in potato.

Fruit opening for dispersion of the seeds is a crucial step for plant reproduction and its control is of major economic importance in agriculture. In collaboration with Dr. Yanofsky (UCSD, California), we have demonstrated that WOX13 plays an important role in controlling Arabidopsis fruit patterning and ensures proper timing of fruit dehiscence by affecting valve margin lignification. These studies may be useful for plant species where control of seed dispersal could generate major economic benefits, such as in oilseed rape production.

Plant hairsor trichomes are specialized epidermal cell protrusions that defend the plant against insect herbivores, UV light and excessive water loss. Trichome formation is controlled by gibberellins and cytokinins, hormones that trigger trichome initiation.  We have found that TEMPRANILLO genes also play critical roles in this process since tempranillo mutants are hairier. In addition to Arabidopsis we study their roles in Artemisia annua, a plant that accumulates a potent antimalarial compound in its trichomes. The amount of this compound per plant is low, therefore we are trying to obtain Artemisia with more trichomes to increase artemisinin production.

Research Projects

  • To unravel the roles of TEM genes in controlling flowering time in response to other genetic pathways, such as age, temperature and light perception.
  • To study the roles of other members of the RAV family in Arabidopsis.
  • Study RAV gene family function in poplar, rice and Artemisia.
  • Mechanisms of photoperiodic tuberization control

Selected Publications

Gonzalez-Schain N.D., Diaz-Mendoza M., Zurczak M., Suarez-Lopez P.
Potato CONSTANS is involved in photoperiodic tuberization in a graft-transmissible manner
(2012) Plant Journal, vol. 70 (4), pp. 678-690

Marin-Gonzalez E., Suarez-Lopez P.
And yet it moves: Cell-to-cell and long-distance signaling by plant microRNAs
(2012) Plant Science, vol. 196, pp. 18-30

Osnato M., Castillejo C., Matias-Hernandez L., Pelaz S.
TEMPRANILLO genes link photoperiod and gibberellin pathways to control flowering in Arabidopsis
(2012) Nature Communications, vol. 3, Art. number 808

Garay-Arroyo A., Ortiz-Moreno E., de la Paz Sanchez M., Murphy A.S., Garcia-Ponce B., Marsch-Martinez N., de Folter S., Corvera-Poire A., Jaimes-Miranda F., Pacheco-Escobedo M.A., Dubrovsky J.G., Pelaz S., Alvarez-Buylla E.R.
The MADS transcription factor XAL2/AGL14 modulates auxin transport during Arabidopsis root development by regulating PIN expression
(2013) EMBO Journal, vol 32 (21), pp. 2884-2895

Romera-Branchat M., Ripoll J.J., Yanofsky M.F., Pelaz S.
The WOX13 homeobox gene promotes replum formation in the Arabidopsis thaliana fruit
(2013) Plant Journal, vol. 73 (1), pp. 37-49