MADS‐Box Genes Controlling Flower Development in Rice

Abstract

The separation between monocot and dicot plants occurred about 120 ‐ 180 million years ago and since then major morphological changes have led to the striking differences that can be observed today. To understand whether, despite these differences, the processes controlling flower development are fundamentally comparable in dicot and monocot species, it is necessary to perform comparative studies. However, until recently flower development has been studied mainly in dicot plant species. Genetic and molecular analyses of two dicot model species, Arabidopsis thaliana and Antirrhinum majus, led to the formulation of the ABC model of flower development that describes how the combined activities of three classes of genes are required to drive flower organ development. This model has recently been extended by the inclusion of two other gene classes, namely D and E, which are involved in ovule development, and petal, stamen and carpel development, respectively. Most of the A, B, C, D and E genes identified so far have been shown to encode MADS‐box transcription factors. In rice a number of regulatory genes belonging to the MADS‐box transcription factor family have been cloned in the last few years and the functions of some of them have been investigated in detail. Here we review the current state of knowledge on rice flower development and focus on MADS‐box genes that determine floral organ identity in this species. We compare results obtained in rice with the information known for Arabidopsis and the differences between these two species are discussed.

Molecular and Genetic Mechanisms of Floral Control

“…This model, initially proposed in the early 1990s based on genetic experiments in Antirrhinum and Arabidopsis, is striking in its simplicity and is applicable to a wide range of angiosperm species, both dicots and monocots, including economically important grass species such as rice and maize Coen and Meyerowitz, 1991;Ambrose et al, 2000;Fornara et al, 2003). The Arabidopsis flower, like most angiosperm flowers, consists of four organ types that are arranged in a series of concentric rings or whorls.…”

Molecular and Phylogenetic Analyses of the Complete MADS-Box Transcription Factor Family in Arabidopsis

“…Judging from the broad variety of MADS-box factor functions in Arabidopsis and in many other plant species (Colombo et al, 1997;Kater et al, 2001;Fornara et al, 2003) and from the phylogenetic analyses of MIKC-type MADS-box genes (Purugganan et al, 1995;Theißen et al, 1996;Münster et al, 1997), it is very likely that this family played a significant role in the evolution of plants.…”

Flowering Syndrome-Hybrid Performance Relationship in Maize 1-Agromonic Traits

“…Genes controlling flowering act in different pathways; response to darkness, response to gibberellins, and to internal plant responses to vernalization and flowering [2,5]. One of the most used models of flowering is the ABC model [6], this model is true for many plants genera including maize (Zea mays L.) [7].…”