Flowering plants exhibit one of two types inflorescence architecture: indeterminate, in which the grows indefinitely, or determinate, a terminal flower is produced. The indeterminate condition thought to have evolved from determinate many times, independently. In mutants distantly related species, 1 Arabidopsis and centroradialis Antirrhinum , inflorescences that are normally converted architecture. gene CENTRORADIALIS ( CEN ) TERMINAL FLOWER TFL1 were shown be homologous, suggests common...

The cycloidea (cyc) and teosinte branched 1 (tb1) genes code for structurally related proteins implicated in the evolution of key morphological traits. However, biochemical function CYC TB1 remains to be demonstrated. To address this problem, we have analysed predicted secondary structure regions conserved between TB1, looked known function. One is form a non-canonical basic-Helix-Loop-Helix (bHLP) structure. This domain also found two rice DNA-binding proteins, PCF1 PCF2, where it has been...

Although curvature of biological surfaces has been considered from mathematical and biophysical perspectives, its molecular developmental basis is unclear. We have studied the cin mutant Antirrhinum , which crinkly rather than flat leaves. Leaves display excess growth in marginal regions, resulting a gradual introduction negative during development. This reflects change shape progression cell-cycle arrest front moving leaf tip toward base. CIN encodes TCP protein expressed downstream front....

To isolate and study genes controlling floral development, we have carried out a large-scale transposon-mutagenesis experiment in Antirrhinum majus. Ten independent homeotic mutations were obtained that could be divided into three classes, depending on whether they affect (1) the identity of organs within same whorl; (2) sometimes also number whorls; (3) fate axillary meristem normally gives rise to flower. The classes phenotypes suggest model for genetic control primordium which class 2 are...

To understand the constraints on biological diversity, we analyzed how selection and development interact to control evolution of inflorescences, branching structures that bear flowers. We show a single developmental model accounts for restricted range inflorescence types observed in nature this is supported by molecular genetic studies. The predicts associations between architecture, climate, life history, which validated empirically. Paths, or evolutionary wormholes, link different...

Shape-Shifting Signals Although orthogonal signaling systems seem to direct various developmental processes, few tissues remain in the same shape as they are at initiation that of final form. Arabidopsis leaves free cell migrations complicate animal development, and thus allowed Kuchen et al. (p. 1092 ) track model trajectory leaf growth under a variety perturbations. Varying values parameters their produced outputs different shapes ranging from obcordate, ovate, oval elliptic, offered...

Understanding the mechanism by which patterned gene activity leads to mechanical deformation of cells and tissues create complex forms is a major challenge for developmental biology. Plants offer advantages addressing this problem because their do not migrate or rearrange during morphogenesis, simplifies analysis. We synthesize results from experimental analysis computational modeling show how interactions between cellulose fibers translate through wall, cell, tissue levels generate plant...

ABSTRACT The overall aerial architecture of flowering plants depends on a group meristematic cells in the shoot apex. We demonstrate that Arabidopsis TERMINAL FLOWER 1 gene has unified effect rate progression apex through different developmental phases. In transgenic which ectopically express 1, both vegetative and reproductive phases are greatly extended. As consequence, these exhibit dramatic changes their morphology, producing an enlarged rosette leaves, followed by highly branched...

The overall morphology of an Arabidopsis plant depends on the behaviour its meristems. Meristems derived from shoot apex can develop into either shoots or flowers. distinction between these alternative fates requires separation function floral meristem identity genes and antagonistic group genes, which includes TERMINAL FLOWER 1. We show that activities are restricted to separate domains by different mechanisms. Meristem such as LEAFY, APETALA 1 CAULIFLOWER, prevent transcription in...

Although much progress has been made in understanding how gene expression patterns are established during development, less is known about these related to the growth of biological shapes. Here we describe conceptual and experimental approaches bridging this gap, with particular reference plant development where lack cell movement simplifies matters. Growth shape change plants can be fully described four types regional parameter: rate, anisotropy, direction, rotation. A key requirement...

In many plant species, self-incompatibility (SI) is genetically controlled by a single multiallelic S locus. Previous analysis of alleles in the Solanaceae, which locus ribonucleases (S RNases) are responsible for stylar expression SI, has demonstrated that allelic diversity predated speciation within this family. To understand how evolved, we investigated molecular basis gametophytic SI Antirrhinum, member Scrophulariaceae, closely related to Solanaceae. We have characterized three...

Hybridization between species can lead to introgression of genes from one another, providing a potential mechanism for preserving and recombining key traits during evolution. To determine the molecular basis such transfers, we analyzed natural polymorphism flower-head development in Senecio. We show that arose by cluster regulatory genes, RAY locus, diploid S. squalidus into tetraploid vulgaris. The are expressed peripheral regions inflorescence meristem, where they promote flower asymmetry...

To understand how genes control floral asymmetry, we have isolated and analyzed the role of RADIALIS (RAD) gene in Antirrhinum. We show that RAD encodes a small MYB-like protein is specifically expressed dorsal region developing flowers. has single domain closely related to one two domains DIV, an antagonistic effect on development. Interactions between other indicate asymmetry depends interplay pairs transcription factors. First, pair TCP proteins regions meristem, leading activation...

To understand how differentiation and growth may be coordinated during development, we have studied the action of CINCINNATA (CIN) gene Antirrhinum. We show that in addition to affecting leaf lamina growth, CIN affects epidermal cell petal lobes. Strong alleles cin give smaller lobes with flat instead conical cells, correlating lobe-specific expression wild type. Moreover, cells at margins are replaced by flatter indicating has a role leaves as well petals. A weak semidominant allele types...