Study of the MADS-box genes expression during floral development in Coffea arabica L.

Author(s)

Raphael Ricon de Oliveira

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia
• Defense date: 2011-02-21

Examining board members

Marcelo Carnier Dornelas; Paulo Mazzafera; Carlos Augusto Colombo

• Advisor: Marcelo Carnier Dornelas

Abstract

The MADS-box gene family encodes transcription factors that act as key regulators in many steps in the development of various organisms. In plants, these genes are involved in determining the identity of reproductive meristems and floral organs as well as in controlling several processes during development. This work aimed to study the expression patterns of putative orthologs of the ABC model genes (APETALA1, APETALA3, AGAMOUS and PISTILATA from Arabidopsis thaliana, and TM6 from Solanum Lycopersicum) in Coffea arabica L. These genes belong to the MADS-box family and are related to the determination of floral organ identity in the model plant A. thaliana. From the CAFEST database of expressed sequence tags, 23 MADS-box gene sequences were identified in coffee. Expression profiles of these genes, determined by RT-PCR, indicated that most of these genes are expressed in flowers and fruits. The analysis of data from optical microscopy and scanning electron microscopy allowed the establishment of a developmental sequence for the establishment of floral organ, facilitating the characterization of the spatial expression patterns of orthologs of the ABC genes by in situ hybridization. A diversified role of conserved genes of the ABC model was proposed for the relatively recent and peculiar specie that is C. arabica. The obtained results aid the understanding of the establishment of floral organs in C. Arabica. Additionally, as many other coffee MADS-box genes were also characterized, other genes, potentially involved in other developmental processes that could be of interest to the industry in the future were also identified. (AU)