Marie Monniaux

• PostDoc Position at Max Planck Institute for Plant Breeding Research

Floral homeotic MADS-box transcription factors ensure the correct morphogenesis of floral organs, which are organized in different cell layers deriving from distinct meristematic layers. How cells from these distinct layers acquire their respective identities and coordinate their growth to ensure normal floral organ morphogenesis is unresolved. Her...

Flower development is the process leading from a reproductive meristem to a mature flower with fully developed floral organs. This multi-step process is complex and involves thousands of genes in intertwined regulatory pathways; navigating through the FLOR-ID website will give an impression of this complexity and of the astonishing amount of work t...

The expression of phased small interfering RNAs caused monkeyflower color evolution.

Petals are typified by their conical epidermal cells that play a predominant role for the attraction and interaction with pollinators. However, cell identities in the petal can be very diverse, with different cell types in subdomains of the petal, in different cell layers, and depending on their adaxial-abaxial or proximo-distal position in the pet...

Floral homeotic MADS-box transcription factors ensure the correct development of floral organs with all their mature features, i.e. organ shape, size, colour and cellular identity. Furthermore, all plant organs develop from clonally-independent cell layers, deriving from the meristematic epidermal (L1) and internal (L2 and L3) layers. How cells fro...

Members of SEPALLATA(SEP) and APETALA1(AP1)/SQUAMOSA(SQUA) MADS-box transcription factor subfamilies were shown to play key roles in floral organ identity determination and floral meristem determinacy in the Rosid species Arabidopsis. Here we present a functional characterization of the seven SEP/AGL6 and four AP1/SQUA genes in the distant Asterid...

Invariant floral forms are important for reproductive success and robust to natural perturbations. Petal number, for example, is invariant in Arabidopsisthaliana flowers. However, petal number varies in the closely related species Cardamine hirsuta, and the genetic basis for this difference between species is unknown. Here we show that divergence i...

The flower of angiosperms is considered to be a major evolutionary innovation that impacted the whole biome. In particular, two properties of the flower are classically linked to its ecological success: bisexuality and a differentiated perianth with sepals and petals. Although the molecular basis for floral organ identity is well understood in exta...

Four petals characterize the flowers of most species in the Brassicaceae family and this phenotype is generally robust to genetic and environmental variation. A variable petal number distinguishes the flowers of Cardamine hirsuta from those of its close relative Arabidopsis thaliana, and allelic variation at many loci contribute to this trait. Howe...

Flowering plants evolved from an unidentified gymnosperm ancestor. Comparison of the mechanisms controlling development in angiosperm flowers and gymnosperm cones may help to elucidate the mysterious origin of the flower. We combined gene expression studies with protein behaviour characterization in Welwitschia mirabilis to test whether the known r...

A conserved genetic toolkit underlies the development of diverse floral forms among angiosperms. However, the degree of conservation vs divergence in the configuration of these gene regulatory networks is less clear. We addressed this question in a parallel genetic study between the closely related species Arabidopsis thaliana and Cardamine hirsuta...

Background and aims: Floral development is remarkably robust in terms of the identity and number of floral organs in each whorl, whereas vegetative development can be quite plastic. This canalization of flower development prevents the phenotypic expression of cryptic genetic variation, even in fluctuating environments. A cruciform perianth with fo...

Invariant petal number is a characteristic of most flowers and is generally robust to genetic and environmental variation. We took advantage of the natural variation found in Cardamine hirsuta petal number to investigate the genetic basis of this trait in a case where robustness was lost during evolution. We used quantitative trait locus (QTL) anal...

Brunkard et al. propose that the identification of novel LEAFY sequences contradicts our model of evolution through promiscuous intermediates. Based on the debate surrounding land plant phylogeny and on our analysis of these interesting novel sequences, we explain why there is no solid evidence to disprove our model.

LEAFY Evolution It is generally believed that redundancy across gene copies allows for the evolution of novel function in proteins. However, it is less clear how single-copy genes with crucial function may evolve. Sayou et al. (p. 645 , published online 16 January; see the Perspective by Kovach and Lamb ) examined the evolution of the essential pla...

##Assembly-Data-START## Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

In indeterminate inflorescences, floral meristems (FM) develop on the flanks of the shoot apical meristem (SAM), at positions determined by auxin maxima. The floral identity of these meristems is conferred by a handful of genes called FM identity genes, among which the LEAFY (LFY) transcription factor plays a prominent role. However, the molecular...

LEAFY (LFY) is a unique transcription factor, highly conserved within land plants. LFY directly regulates a set of genes participating in floral development in angiosperms (flowering plants), but its role in the other groups of land plants is unknown, except in the moss Physcomitrella patens where the LFY ortholog (PpLFY) regulates the first cell d...

The transition from vegetative growth to flower formation is critical for the survival of flowering plants. The plant-specific transcription factor LEAFY (LFY) has central, evolutionarily conserved roles in this process, both in the formation of the first flower and later in floral patterning. We performed genome-wide binding and expression studies...

Despite great advances in sequencing technologies, generating functional information for nonmodel organisms remains a challenge. One solution lies in an improved ability to predict genetic circuits based on primary DNA sequence in combination with detailed knowledge of regulatory proteins that have been characterized in model species. Here, we focu...

The LEAFY (LFY) gene of Arabidopsis and its homologs in other angiosperms encode a unique plant-specific transcription factor that assigns the floral fate of meristems and plays a key role in the patterning of flowers, probably since the origin of flowering plants. LFY-like genes are also found in gymnosperms, ferns and mosses that do not produce f...