Late-GPA-Plants: Characterisation of the Global Proliferation Arrest and its potential as a target for cereal breeding programmes

Paz Merelo Cremades obtained her degree in Agronomic Engineering from the Polytechnic University of Valencia in 2006 and after completing her final thesis at the Valencian Institute of Agricultural Research (IVIA).

In 2007 she received a grant from the Instituto Nacional de Investigaciones Agrarias (National Agricultural Research Institute – INIA in its initials in Spanish) for her doctoral training (2007-2011) at the IVIA. During this stage she worked on genomic approaches aimed at understanding the molecular basis of citrus abscission.

From 2012-2016 she conducted her post-doctoral research at the European Molecular Biology Laboratory (EMBL, Germany), where she studied the molecular mechanisms that regulate the pattern of organ development in Arabidopsis thaliana.

SinceSeptember 2018 and until 2021, she was a ComFuturo researcher at the Institute of Molecular and Cellular Biology of Plants (IBMCP), where she developed her ComFuturo project “Characterisation of the Global Proliferation Arrest and its potential as a target in cereal breeding programs.“.

Project Summary

Many species of annual and some perennial plants, including a large number of economically important crops, belong to the monocarpic group of plants. These have a single reproductive phase, after which they die. In monocarpic plants, after the production of a certain number of fruits, the activity of the reproductive meristems stops in a coordinated manner, these being groups of undifferentiated or meristematic cells (equivalent to the stem cells of animals) that give rise to the floral organs. As a consequence of this halt in meristematic activity, flower and fruit production ceases. This process is called Global Proliferation Arrest and is an evolutionary adaptation to ensure the redistribution of nutrients towards seed production. From an agronomic point of view, the Global Proliferation Arrest process is an important target in crop improvement programmes since it determines the duration of the reproductive phase and, therefore, the final fruit and seed production.

The overall aim of the proposed project is to define the gene interactions and signals that control the Global Proliferation Arrest. In this way, morphological and genetic markers of the process can be isolated. These factors will be key control points to act upon through biotechnological and agronomic strategies to delay the Global Proliferation Arrest and thus prolong the productive phase in species of economic importance such as maize and wheat. To this end, the problem will be approached from different angles using molecular and cellular biology, genetics and image analysis techniques (live imaging).

Application: The continuous growth of the world population requires the development of strategies aimed at increasing crop productivity to ensure human food supply. In addition, climate change is negatively affecting many crops, reducing their productivity. This project aims to identify genes that regulate the duration of the reproductive phase of plants and then develop biotechnological strategies to increase crop production. The second part of the project aims to transfer the knowledge acquired to species of agronomic interest such as corn and wheat. These cereals, together with rice, are the basis of human nutrition and their grains have high nutritional value.

This image shows the model species (Arabidopsis thaliana) with which this project will work. The inflorescent meristem, located at the apex of the plant, has been highlighted because it is the structure where the process under study takes place (Global Proliferation Arrest). One of the methods to be used to characterise this process is live imaging based on confocal microscopy (image on the right). The basic knowledge generated in Arabidopsis by this technique and others based on molecular biology and genetics will later be used to characterise the process in maize and wheat.

Scientific production derived from ComFuturo Late-GPA-Plants Project

Scientific articles

P. Merelo; I. González; C. Ferrándiz (2021). A cellular analysis of Arabidopsis meristem activity at the end of flowering points to cytokinin as a major regulator of proliferative arrest. CURRENT BIOLOGY. DOI: 10.1016/j.cub.2021.11.069


Works presented at conferences

P. Merelo; I. González; C. Ferrándiz. Characterization of the cellular and molecular events controlling the proliferative arrest in Arabidopsis thaliana. XV Reunión de Biología Molecular de Plantas. Oral presentation. Online. 26/11/2020-27/11/2020


P. Merelo; I. González; C. Ferrándiz. Characterization of the molecular and signaling events regulating the proliferative arrest in Arabidopsis thaliana. The At the Forefront of Plant Research 2019 Congress. Poster. Barcelona, Spain. 6/05/2019-8/05/2019


P. Merelo; I. González; C. Ferrándiz. Patterns of cytokinin and auxin distribution during the proliferative arrest of Arabidopsis thaliana inflorescence meristems. Small Molecules in Plant Research Symposium. Poster. Valencia, Spain. 10/12/2019-11/12/2019