In all higher plants studied to date, the anthocyanin pigment pathway is regulated by a suite of transcription factors that include Myb, bHLH and WD-repeat proteins. However, in Arabidopsis thaliana, Myb regulators remain be conclusively identified, little known about regulation TTG1-dependent transcriptional complexes. Previous overexpression PAP1 suggested genes from entire phenylpropanoid are targets Myb/bHLH/WD-repeat complexes Arabidopsis, contrast other plants. Here we demonstrate...

GLABRA3 (GL3) encodes a bHLH protein that interacts with the WD repeat protein, TTG1. GL3 overexpression suppresses trichome defect of pleiotropic ttg1 mutations. However, single gl3 mutations only affect pathway modest number reduction. A novel unlinked bHLH-encoding locus is described here, ENHANCER OF (EGL3). When mutated, egl3 gives totally glabrous plants in mutant background. The double mutant, egl3, has phenotype like having defective anthocyanin production, seed coat mucilage and...

Arabidopsis trichome development and differentiation is a well-studied model for plant cell-fate determination morphogenesis. Mutations in TRANSPARENT TESTA GLABRA1 (TTG1) result several pleiotropic defects including an almost complete lack of trichomes. The complex phenotype caused by ttg1 mutations suppressed ectopic expression the maize anthocyanin regulator R. Here it demonstrated that locus GLABRA3 (GL3) encodes R homolog. GL3 (GL1) interact when overexpressed together plants. Yeast...

Anthocyanin pathway-specific transcriptional activators R and C1 from the monocot maize were expressed in two dicots, Arabidopsis thaliana Nicotiana tabacum. Expression of caused augmented anthocyanin pigmentation both plant species trichome (hair) production Arabidopsis. Alone, had no effect. Hybrid transgenic expressing produced anthocyanins root, petal, stamen tissues that normally never express anthrocyanins. When was transparent testa glabrous (without trichomes) mutant Arabidopsis,...

Morphologically normal plants were regenerated from Nicotiana plumbaginifolia cells transformed with an Agrobacterium tumefaciens strain containing a tumor-inducing plasmid chimeric gene for kanamycin resistance. The presence of the in was demonstrated by Southern hybridization analysis, and its expression plant tissues confirmed ability leaf segments to form callus on media at concentrations that normally inhibitory. Progeny derived several inherited foreign Mendelian manner.

Targeted mutagenesis is an essential tool of reverse genetics that could be used experimentally to investigate basic plant biology or modify crop plants for improvement important agricultural traits. Although targeted routine in several model organisms including yeast and mouse, efficient widely usable methods generate modifications genes are not currently available. In this study we investigated the efficacy a targeted-mutagenesis approach based on zinc-finger nucleases (ZFNs). procedure,...

The position-dependent specification of the hair and non-hair cell types in Arabidopsis root epidermis provides a simple model for study fate determination plants. Several putative transcriptional regulators are known to influence this decision. Indirect evidence from studies with maize R gene has been used suggest that bHLH transcription factor also participates process. We show two genes encoding proteins, GLABRA3(GL3) ENHANCER OF GLABRA3 (EGL3), act partially redundant manner specify...

A network of three classes proteins consisting bHLH and MYB transcription factors, a WD40 repeat protein, TRANSPARENT TESTA GLABRA1 (TTG1), act in concert to activate trichome initiation patterning. Using YFP-TTG1 translational fusions, we show that TTG1 is expressed ubiquitously Arabidopsis leaves preferentially localized the nuclei trichomes at all developmental stages. conditional transgenic allele, demonstrate directly targets same genes as protein GLABRA3 (GL3). In vivo binding R2R3-MYB...

Abstract Endosperm, a storage tissue in the angiosperm seed, provides nutrients to embryo during seed development and/or developing seedling germination. A major event endosperm is transition between syncytial phase, which nuclei undergo many rounds of mitosis without cytokinesis, and cellularized cell walls form around nuclei. The molecular processes controlling this phase are not understood. In agl62 seeds, cellularizes prematurely, indicating that AGL62 required for suppression...

Endosperm is an absorptive structure that supports embryo development or seedling germination in angiosperms. The endosperm of cereals a main source food, feed, and industrial raw materials worldwide. However, the genetic networks regulate cell differentiation remain largely unclear. As first step toward characterizing these networks, we profiled mRNAs five major types differentiating four maternal compartments maize (Zea mays) kernel. Comparisons mRNA populations revealed diverged gene...

The specification of the hair and non-hair cells in Arabidopsis root epidermis provides a useful model for study cell fate determination plants. A network putative transcriptional regulators, including related bHLH proteins GLABRA3 (GL3) ENHANCER OF (EGL3), is known to influence patterning these types. Here, we analyze expression regulation GL3 EGL3 during development. Although they are thought act both types, surprisingly found that gene RNA accumulation occurs preferentially developing...

The Arabidopsis mutant ttg lacks both trichomes (epidermal hairs) and anthocyanin pigments. Trichomes anthocyanins are restored by the constitutive expression of maize transcriptional regulator (R). an R-glucocorticoid receptor chimeric protein results in a steroid hormone-dependent, conditional allele R that functions whole plants. response to pulses hormone was used define pattern timing trichome formation on developing leaf epidermis. Each adaxial epidermal cell appears have equal...

A morphological description of the differentiation outer integument Arabidopsis thaliana seed is presented. The period covered starts at about octant embryo stage, extends to mature seed, and concludes beyond that initial stages imbibition. During this two-cell-layered goes through a dramatic process. cell layer secretes mucilage in ring between plasma membrane wall corners cell. This secretion forces cytoplasm into columnar shape center Before during process, starch granules are produced,...

Abstract During plant reproduction, the central cell of female gametophyte becomes fertilized to produce endosperm, a storage tissue that nourishes developing embryo within seed. The molecular mechanisms controlling specification and differentiation are poorly understood. We identified mutant in Arabidopsis thaliana, fem111, is affected development. In fem111 gametophytes, cell's nucleolus vacuole fail mature properly. addition, endosperm development not initiated after fertilization...

Transformed Arabidopsis thaliana plants have been produced by a modified leaf disk transformation-regeneration method. Leaf pieces from sterilely grown were precultured for 2 days and inoculated with an Agrobacterium tumefaciens strain containing avirulent Ti (tumor-inducing) plasmid chimeric gene encoding hygromycin resistance. After cocultivation days, the placed on medium that selects Shoots regenerated within 3 months excised, rooted, transferred to soil. Transformation was confirmed...

Arabidopsis trichomes are branched, single-celled epidermal hairs. These specialized cells provide a convenient model for investigating the specification of cell fate in plants. Two key genes regulating initiation trichome development GLABROUS1 (GL1) and TRANSPARENT TESTA GLABRA (TTG). GL1 is member myb gene family. The maize R gene, which can functionally complement ttg mutation, encodes basic helix-loop-helix protein. We used constitutively expressed copies to test hypotheses about roles...

The development of trichomes (leaf hairs) from pluripotent epidermal cells in Arabidopsis (Arabidopsis thaliana) provides a powerful system to investigate the regulatory motifs involved plant cell differentiation. We show here that trichome initiation is triggered within 4 h induction GLABRA3 (GL3) basic helix-loop-helix transcription factor. Within this developmental window, GL3 binds promoters at least three genes previously implicated and patterning (GL2, CAPRICE, ENHANCER OF TRIPTYCHON...

Promoters that allow the selective induction of gene expression in vivo constitute an important methodology eukaryotic organisms such as yeast and fruit fly, but to date no system has been described for higher plants. Given fact mammalian steroid receptors can function hormone-dependent inducers heterologous systems, feasibility using hormones plant was investigated. Here it is shown glucocorticoid receptor expressed cells capable activating a test linked response elements, providing...