Tip growth defective1 interacts with cellulose synthase A3 to regulate cellulose biosynthesis in Arabidopsis.

AtTIP1 physically and genetically interacts with AtCESA3. AtCESA3 undergoes S-acylation, possibly mediated by AtTIP1, suggesting a specific role of AtTIP1 in cellulose biosynthesis and plant development. S-acylation is a reversible post-translational lipid modification of proteins catalyzed by protein S-acyl transferases (PATs).

NCP2/RHD4/SAC7, SAC6 and SAC8 phosphoinositide phosphatases are required for PtdIns4P and PtdIns(4,5)P2 homeostasis and Arabidopsis development.

Phosphoinositides play important roles in plant growth and development. Several SAC domain phosphoinositide phosphatases have been reported to be important for plant development. Here, we show functional analysis of SUPPRESSOR OF ACTIN 6 (SAC6) to SAC8 in Arabidopsis, a subfamily of phosphoinositide phosphatases containing SAC-domain and two transmembrane motifs.

Effect of combined arsenic and lead exposure on their uptake and translocation in Indian mustard.

Phytoremediation makes use of hyperaccumulating plants to remove potentially toxic elements (PTEs) from soil selectively. Most researches examining hyperaccumulators focused on how they act on a single PTE contaminant. However, there is more than one kind of PTEs in most contaminated soils.

The ESCRT-I components VPS28A and VPS28B are essential for auxin-mediated plant development.

The highly conserved endosomal sorting complex required for transport (ESCRT) pathway plays critical roles in endosomal sorting of ubiquitinated plasma membrane proteins for degradation. However, the functions of many components of the ESCRT machinery in plants remain unsolved. Here we show that the ESCRT-I subunits VPS28A and VPS28B are functionally redundant and required for embryonic development in Arabidopsis.

Genes Regulate Jasmonate Accumulation and Plant Development.

The MOB1 proteins are highly conserved in yeasts, animals, and plants. Previously, we showed that the Arabidopsis () gene () plays critical roles in auxin-mediated plant development. Here, we report that and redundantly and negatively regulate jasmonate (JA) accumulation and function in Arabidopsis development.

Arabidopsis AGC protein kinases IREH1 and IRE3 control root skewing.

AGC protein kinases play important roles in plant growth and development. Several AGC kinases in Arabidopsis have been functionally characterized. However, the "AGC Other" subfamily, including IRE, IREH1, IRE3 and IRE4, has not been well understood.

Modulation of Auxin Signaling and Development by Polyadenylation Machinery.

Polyadenylation influences gene expression by affecting mRNA stability, transport, and translatability. Here, we report that Cleavage stimulation Factor 77 (AtCstF77), a component of the pre-mRNA 3'-end polyadenylation machinery, affects polyadenylation site (PAS) selection in transcripts of some auxin signaling genes in Arabidopsis (). Disruption of reduced auxin sensitivity and decreased the expression of the auxin reporter - Null mutations of caused severe developmental defects, but were not lethal as previously reported.

Possible Interactions between the Biosynthetic Pathways of Indole Glucosinolate and Auxin.

Glucosinolates (GLS) are a group of plant secondary metabolites mainly found in Cruciferous plants, share a core structure consisting of a β-thioglucose moiety and a sulfonated oxime, but differ by a variable side chain derived from one of the several amino acids. These compounds are hydrolyzed upon cell damage by thioglucosidase (myrosinase), and the resulting degradation products are toxic to many pathogens and herbivores. Human beings use these compounds as flavor compounds, anti-carcinogens, and bio-pesticides.

NCP1/AtMOB1A Plays Key Roles in Auxin-Mediated Arabidopsis Development.

MOB1 protein is a core component of the Hippo signaling pathway in animals where it is involved in controlling tissue growth and tumor suppression. Plant MOB1 proteins display high sequence homology to animal MOB1 proteins, but little is known regarding their role in plant growth and development. Herein we report the critical roles of Arabidopsis MOB1 (AtMOB1A) in auxin-mediated development in Arabidopsis.

Auxin overproduction in shoots cannot rescue auxin deficiencies in Arabidopsis roots.

Auxin plays an essential role in root development. It has been a long-held dogma that auxin required for root development is mainly transported from shoots into roots by polarly localized auxin transporters. However, it is known that auxin is also synthesized in roots.

The jasmonic acid signaling pathway is linked to auxin homeostasis through the modulation of YUCCA8 and YUCCA9 gene expression.

Interactions between phytohormones play important roles in the regulation of plant growth and development, but knowledge of the networks controlling hormonal relationships, such as between oxylipins and auxins, is just emerging. Here, we report the transcriptional regulation of two Arabidopsis YUCCA genes, YUC8 and YUC9, by oxylipins. Similar to previously characterized YUCCA family members, we show that both YUC8 and YUC9 are involved in auxin biosynthesis, as demonstrated by the increased auxin contents and auxin-dependent phenotypes displayed by gain-of-function mutants as well as the significantly decreased indole-3-acetic acid (IAA) levels in yuc8 and yuc8/9 knockout lines.

Pattern of auxin and cytokinin responses for shoot meristem induction results from the regulation of cytokinin biosynthesis by AUXIN RESPONSE FACTOR3.

De novo organ regeneration is an excellent biological system for the study of fundamental questions regarding stem cell initiation, cell fate determination, and hormone signaling. Despite the general belief that auxin and cytokinin responses interact to regulate de novo organ regeneration, the molecular mechanisms underlying such a cross talk are little understood. Here, we show that spatiotemporal biosynthesis and polar transport resulted in local auxin distribution in Arabidopsis (Arabidopsis thaliana), which in turn determined the cytokinin response during de novo shoot regeneration.

Conversion of tryptophan to indole-3-acetic acid by TRYPTOPHAN AMINOTRANSFERASES OF ARABIDOPSIS and YUCCAs in Arabidopsis.

Auxin is an essential hormone, but its biosynthetic routes in plants have not been fully defined. In this paper, we show that the TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS (TAA) family of amino transferases converts tryptophan to indole-3-pyruvate (IPA) and that the YUCCA (YUC) family of flavin monooxygenases participates in converting IPA to indole-3-acetic acid, the main auxin in plants. Both the YUCs and the TAAs have been shown to play essential roles in auxin biosynthesis, but it has been suggested that they participate in two independent pathways.

NPY genes play an essential role in root gravitropic responses in Arabidopsis.

Plants can sense the direction of gravity and orient their growth to ensure that roots are anchored in soil and that shoots grow upward. Gravitropism has been studied extensively using Arabidopsis genetics, but the exact mechanisms for gravitropism are not fully understood. Here, we demonstrate that five NPY genes play a key role in Arabidopsis root gravitropism.

REVEILLE1, a Myb-like transcription factor, integrates the circadian clock and auxin pathways.

The circadian clock modulates expression of a large fraction of the Arabidopsis genome and affects many aspects of plant growth and development. We have discovered one way in which the circadian system regulates hormone signaling, identifying a node that links the clock and auxin networks. Auxin plays key roles in development and responses to environmental cues, in part through regulation of plant growth.

An allelic mutant series of ATM3 reveals its key role in the biogenesis of cytosolic iron-sulfur proteins in Arabidopsis.

The ATP-binding cassette transporters of mitochondria (ATMs) are highly conserved proteins, but their function in plants is poorly defined. Arabidopsis (Arabidopsis thaliana) has three ATM genes, namely ATM1, ATM2, and ATM3. Using a collection of insertional mutants, we show that only ATM3 has an important function for plant growth.

NPY genes and AGC kinases define two key steps in auxin-mediated organogenesis in Arabidopsis.

Auxin is an essential regulator of plant organogenesis. Most key genes in auxin biosynthesis, transport, and signaling belong to gene families, making it difficult to conduct genetic analysis of auxin action in plant development. Herein we report the functional analysis of several members of 2 gene families (NPY/ENP/MAB4 genes and AGC kinases) in auxin-mediated organogenesis and their relationships with the YUC family of flavin monooxygenases that are essential for auxin biosynthesis.

Rapid synthesis of auxin via a new tryptophan-dependent pathway is required for shade avoidance in plants.

Plants grown at high densities perceive a decrease in the red to far-red (R:FR) ratio of incoming light, resulting from absorption of red light by canopy leaves and reflection of far-red light from neighboring plants. These changes in light quality trigger a series of responses known collectively as the shade avoidance syndrome. During shade avoidance, stems elongate at the expense of leaf and storage organ expansion, branching is inhibited, and flowering is accelerated.

NPY1, a BTB-NPH3-like protein, plays a critical role in auxin-regulated organogenesis in Arabidopsis.

Auxin is an essential regulator for plant development. To elucidate the mechanisms by which auxin regulates plant development, we isolated an Arabidopsis mutant naked pins in yuc mutants 1 (npy1) that develops pin-like inflorescences and fails to initiate any flowers in yuc1 yuc4, a background that is defective in auxin biosynthesis. The phenotypes of npy1 yuc1 yuc4 triple mutants closely resemble those of Arabidopsis mutants pin-formed1 (pin1), pinoid (pid), and monopteros (mp), which are defective in either auxin transport or auxin signaling.

Auxin synthesized by the YUCCA flavin monooxygenases is essential for embryogenesis and leaf formation in Arabidopsis.

Auxin plays a key role in embryogenesis and seedling development, but the auxin sources for the two processes are not defined. Here, we demonstrate that auxin synthesized by the YUCCA (YUC) flavin monooxygenases is essential for the establishment of the basal body region during embryogenesis and the formation of embryonic and postembryonic organs. Both YUC1 and YUC4 are expressed in discrete groups of cells throughout embryogenesis, and their expression patterns overlap with those of YUC10 and YUC11 during embryogenesis.

Auxin biosynthesis by the YUCCA flavin monooxygenases controls the formation of floral organs and vascular tissues in Arabidopsis.

Auxin biosynthesis in plants has remained obscure although auxin has been known for decades as a key regulator for plant growth and development. Here we define the YUC gene family and show unequivocally that four of the 11 predicted YUC flavin monooxygenases (YUC1, YUC2, YUC4, and YUC6) play essential roles in auxin biosynthesis and plant development. The YUC genes are mainly expressed in meristems, young primordia, vascular tissues, and reproductive organs.

Genetic and chemical analyses of the action mechanisms of sirtinol in Arabidopsis.

The synthetic molecule sirtinol was shown previously to activate the auxin signal transduction pathway. Here we present a combination of genetic and chemical approaches to elucidate the action mechanisms of sirtinol in Arabidopsis. Analysis of sirtinol derivatives indicated that the "active moiety" of sirtinol is 2-hydroxy-1-naphthaldehyde (HNA), suggesting that sirtinol undergoes a series of transformations in Arabidopsis to generate HNA, which then is converted to 2-hydroxy-1-naphthoic acid (HNC), which activates auxin signaling.

AtCAND1, a HEAT-repeat protein that participates in auxin signaling in Arabidopsis.

Auxin affects many aspects of plant growth and development. We previously used chemical genetics to dissect auxin-signaling mechanisms and identified a small molecule, sirtinol, that constitutively activated auxin signaling (Y. Zhao et al.

Gene expression profiling of Arabidopsis thaliana in compatible plant-aphid interactions.

Phloem feeding involves unique biological interactions between the herbivore and its host plant. The economic importance of aphids, whiteflies, and other phloem-feeding insects as pests has prompted research to isolate sources of resistance to piercing-sucking insects in crops. However, little information exists about the molecular nature of plant sensitivity to phloem feeding.