Table of Contents

In this study, the characterization of Orr^Ds, a dominant transposon-tagged tomato mutant deficient in the NDH-M subunit, provided evidence that the plastid NAD(P)H dehydrogenase (NDH) complex is essential for the fruit ripening process and related metabolism.

Brassinosteroid (BR) homeostasis is established by the regulatory circuit between receptor BRI1-mediated signaling and BR synthesis. RAVL1 modulates the strength of the circuit by activating expression of both BRI1 and synthetic genes and is necessary for feedback responses to BR levels.

This study identifies AMSH3 as a major deubiquitinating enzyme in Arabidopsis that hydrolyzes ubiquitin chains in vitro and in vivo. It finds that AMSH3 is essential for proper vacuole biogenesis, trafficking from the Golgi to the vacuole, and the vacuolar trafficking of endocytosed cargo.

Floral scent and color play major roles in the plant's life cycle. Using petunia as a model system, a MYB-like factor was identified that transcriptionally regulates floral scent but not pigmentation. The multilayered regulation allows efficient control of metabolic flux in the phenylpropanoid pathway.

This work identifies the putative transcription factor gene VDD as a direct target of MADS box proteins that regulate ovule development. It finds that antipodal and synergid cell identity and/or differentiation are affected in vdd mutant female gametophytes, providing insights into the pathways regulated by the ovule identity factors.

Plant development depends on the balance of stem cell renewal and differentiation in several stem cell niches that is achieved by yet unknown regulatory mechanisms. Using inducible RNA interference-mediated downregulation, Arabidopsis RETINOBLASTOMA-RELATED protein is shown to regulate the proliferation, maintenance, and differentiation of stem cells and organ production from stem cell niches.

The Arabidopsisgene ABI3 shows developmentally regulated alternative splicing. ABI3-α and ABI3-β splice variants encode full-length and truncated ABI3 proteins, respectively. The conserved splicing factor SUA reduces splicing of a cryptic ABI3 intron, which leads to the accumulation of ABI3-α. Mutations in sua suppress the frameshift mutant abi3-5 by restoring its reading frame.

Inherited transpositions of the endogenous Ds create stable insertion lines, a resource for targeting gene knockouts and examining mechanisms of transposition. Ds preferentially inserts into genes, at target sites within 16-bpair segments of DNA with specific structural properties. These results suggest approaches to predict insertion sites in transposon mutagenesis experiments.

This article describes the molecular analysis of large contiguous sequences produced from the bread wheat genome. It provides novel insights into the number, distribution, and density of genes along chromosome 3B and reveals an unexpectedly high amount of noncollinear genes compared to model grass genomes.

This article describes the molecular analysis of large contiguous sequences produced from the bread wheat genome. It provides novel insights into the number, distribution, and density of genes along chromosome 3B and reveals an unexpectedly high amount of noncollinear genes compared to model grass genomes.

This work identifies a group of WRKY transcription factors that function as negative abscisic acid (ABA) signaling regulators acting as transcription repressors directly downstream of a previously identified ABA receptor ABAR, describing an ABA signaling pathway from primary events to downstream gene expression.

Sulfur deprivation of the unicellular alga Chlamydomonas reinhardtii triggers massive changes in the levels of transcripts associated with sulfate assimilation, the synthesis and turnover of sulfur-containing metabolites, and the remodeling of the photosynthetic apparatus and cell wall. These responses are critical for survival of the organism under sulfur deprivation conditions.

Pharmacological and genetic impairments of phospholipase A₂ (PLA₂) caused anatomical alterations of the trans-Golgi side and defects in trafficking of auxin-transporting PIN proteins to the plasma membrane in Arabidopsis root epidermal cells. The results implicate PLA₂-mediated lipid hydrolysis in PIN trafficking.

This article describes the molecular analysis of large contiguous sequences produced from the bread wheat genome. It provides novel insights into the number, distribution, and density of genes along chromosome 3B and reveals an unexpectedly high amount of noncollinear genes compared to model grass genomes.

This study describes a newly isolated altered auxin response mutant. It finds that the mutant exhibits a reduction in polar auxin transport caused by a decrease in the levels of members of the PIN family of auxin efflux proteins.

This work identifies the putative transcription factor gene VDD as a direct target of MADS box proteins that regulate ovule development. It finds that antipodal and synergid cell identity and/or differentiation are affected in vdd mutant female gametophytes, providing insights into the pathways regulated by the ovule identity factors.

Inherited transpositions of the endogenous Ds create stable insertion lines, a resource for targeting gene knockouts and examining mechanisms of transposition. Ds preferentially inserts into genes, at target sites within 16-bpair segments of DNA with specific structural properties. These results suggest approaches to predict insertion sites in transposon mutagenesis experiments.

The target of rapamycin (TOR) pathway, which is known to regulate cell growth in eukaryotes, is shown to affect cell wall structure in plants. ROL5 (REPRESSOR of LRX1) is identified as a possible mitochondrial component of the TOR pathway.

This work examines translocation of the flax rust effector protein AvrM, showing that it accumulates in the haustorial wall and extracellular matrix and is delivered into the host cytoplasm. Protein fusions expressed in the plant showed that AvrM can be secreted by the plant and subsequently internalized in the absence of pathogen.

This work identifies a group of WRKY transcription factors that function as negative abscisic acid (ABA) signaling regulators acting as transcription repressors directly downstream of a previously identified ABA receptor ABAR, describing an ABA signaling pathway from primary events to downstream gene expression.

This work identifies the putative transcription factor gene VDD as a direct target of MADS box proteins that regulate ovule development. It finds that antipodal and synergid cell identity and/or differentiation are affected in vdd mutant female gametophytes, providing insights into the pathways regulated by the ovule identity factors.

This work examines translocation of the flax rust effector protein AvrM, showing that it accumulates in the haustorial wall and extracellular matrix and is delivered into the host cytoplasm. Protein fusions expressed in the plant showed that AvrM can be secreted by the plant and subsequently internalized in the absence of pathogen.

In this study, the characterization of Orr^Ds, a dominant transposon-tagged tomato mutant deficient in the NDH-M subunit, provided evidence that the plastid NAD(P)H dehydrogenase (NDH) complex is essential for the fruit ripening process and related metabolism.

This study describes a newly isolated altered auxin response mutant. It finds that the mutant exhibits a reduction in polar auxin transport caused by a decrease in the levels of members of the PIN family of auxin efflux proteins.

This work examines translocation of the flax rust effector protein AvrM, showing that it accumulates in the haustorial wall and extracellular matrix and is delivered into the host cytoplasm. Protein fusions expressed in the plant showed that AvrM can be secreted by the plant and subsequently internalized in the absence of pathogen.

This study describes a newly isolated altered auxin response mutant. It finds that the mutant exhibits a reduction in polar auxin transport caused by a decrease in the levels of members of the PIN family of auxin efflux proteins.

This article describes the molecular analysis of large contiguous sequences produced from the bread wheat genome. It provides novel insights into the number, distribution, and density of genes along chromosome 3B and reveals an unexpectedly high amount of noncollinear genes compared to model grass genomes.

Sulfur deprivation of the unicellular alga Chlamydomonas reinhardtii triggers massive changes in the levels of transcripts associated with sulfate assimilation, the synthesis and turnover of sulfur-containing metabolites, and the remodeling of the photosynthetic apparatus and cell wall. These responses are critical for survival of the organism under sulfur deprivation conditions.

This work identifies the putative transcription factor gene VDD as a direct target of MADS box proteins that regulate ovule development. It finds that antipodal and synergid cell identity and/or differentiation are affected in vdd mutant female gametophytes, providing insights into the pathways regulated by the ovule identity factors.

This article describes the molecular analysis of large contiguous sequences produced from the bread wheat genome. It provides novel insights into the number, distribution, and density of genes along chromosome 3B and reveals an unexpectedly high amount of noncollinear genes compared to model grass genomes.

Brassinosteroid (BR) homeostasis is established by the regulatory circuit between receptor BRI1-mediated signaling and BR synthesis. RAVL1 modulates the strength of the circuit by activating expression of both BRI1 and synthetic genes and is necessary for feedback responses to BR levels.

Plant development depends on the balance of stem cell renewal and differentiation in several stem cell niches that is achieved by yet unknown regulatory mechanisms. Using inducible RNA interference-mediated downregulation, Arabidopsis RETINOBLASTOMA-RELATED protein is shown to regulate the proliferation, maintenance, and differentiation of stem cells and organ production from stem cell niches.

Pharmacological and genetic impairments of phospholipase A₂ (PLA₂) caused anatomical alterations of the trans-Golgi side and defects in trafficking of auxin-transporting PIN proteins to the plasma membrane in Arabidopsis root epidermal cells. The results implicate PLA₂-mediated lipid hydrolysis in PIN trafficking.

This work examines the interactions among MOTHER OF FT AND TFL1 (MFT) and the genes of the abscisic acid (ABA) signaling pathways in the initiation of germination, finding that MFT expression is regulated by key ABA- and gibberellin-responsive factors and MFT in turn also regulates ABA signaling, providing a feedback loop.

Gametophytes of the fern Pteris vittata can accumulate and tolerate more than 1% of their dry weight as arsenic. The authors provide evidence that the ACR3 arsenic transporter protein plays an important role in tolerance to high levels of arsenic by transporting arsenic into the vacuole.

This study identifies AMSH3 as a major deubiquitinating enzyme in Arabidopsis that hydrolyzes ubiquitin chains in vitro and in vivo. It finds that AMSH3 is essential for proper vacuole biogenesis, trafficking from the Golgi to the vacuole, and the vacuolar trafficking of endocytosed cargo.

This article describes the molecular analysis of large contiguous sequences produced from the bread wheat genome. It provides novel insights into the number, distribution, and density of genes along chromosome 3B and reveals an unexpectedly high amount of noncollinear genes compared to model grass genomes.

The target of rapamycin (TOR) pathway, which is known to regulate cell growth in eukaryotes, is shown to affect cell wall structure in plants. ROL5 (REPRESSOR of LRX1) is identified as a possible mitochondrial component of the TOR pathway.

This work identifies the putative transcription factor gene VDD as a direct target of MADS box proteins that regulate ovule development. It finds that antipodal and synergid cell identity and/or differentiation are affected in vdd mutant female gametophytes, providing insights into the pathways regulated by the ovule identity factors.

This article describes the molecular analysis of large contiguous sequences produced from the bread wheat genome. It provides novel insights into the number, distribution, and density of genes along chromosome 3B and reveals an unexpectedly high amount of noncollinear genes compared to model grass genomes.

Inherited transpositions of the endogenous Ds create stable insertion lines, a resource for targeting gene knockouts and examining mechanisms of transposition. Ds preferentially inserts into genes, at target sites within 16-bpair segments of DNA with specific structural properties. These results suggest approaches to predict insertion sites in transposon mutagenesis experiments.

Pharmacological and genetic impairments of phospholipase A₂ (PLA₂) caused anatomical alterations of the trans-Golgi side and defects in trafficking of auxin-transporting PIN proteins to the plasma membrane in Arabidopsis root epidermal cells. The results implicate PLA₂-mediated lipid hydrolysis in PIN trafficking.

Pharmacological and genetic impairments of phospholipase A₂ (PLA₂) caused anatomical alterations of the trans-Golgi side and defects in trafficking of auxin-transporting PIN proteins to the plasma membrane in Arabidopsis root epidermal cells. The results implicate PLA₂-mediated lipid hydrolysis in PIN trafficking.

The target of rapamycin (TOR) pathway, which is known to regulate cell growth in eukaryotes, is shown to affect cell wall structure in plants. ROL5 (REPRESSOR of LRX1) is identified as a possible mitochondrial component of the TOR pathway.

The Arabidopsisgene ABI3 shows developmentally regulated alternative splicing. ABI3-α and ABI3-β splice variants encode full-length and truncated ABI3 proteins, respectively. The conserved splicing factor SUA reduces splicing of a cryptic ABI3 intron, which leads to the accumulation of ABI3-α. Mutations in sua suppress the frameshift mutant abi3-5 by restoring its reading frame.

A crucial step for diseases caused by phytopathogenic fungi is the penetration of the plant cuticle. Here, we highlight that two conserved plasma membrane proteins are required for plant surface sensing and regulate the penetration process via MAP kinase signaling.

This article reports that DWA1 and DWA2 may be the substrate receptors for a CULLIN E3 ligase and that they interact with themselves and each other. Heterodimeric cooperation between DWAs is a previously unknown regulatory mechanism for the action of CULLIN E3 ligases.

Pharmacological and genetic impairments of phospholipase A₂ (PLA₂) caused anatomical alterations of the trans-Golgi side and defects in trafficking of auxin-transporting PIN proteins to the plasma membrane in Arabidopsis root epidermal cells. The results implicate PLA₂-mediated lipid hydrolysis in PIN trafficking.

This work examines the repair of DNA double-strand breaks in the mitochondria and plastids of Arabidopsis. The crystal structures of a Whirly protein bound to single-stranded DNA suggest a role for these proteins in DNA damage tolerance in the organelles.

This article describes the molecular analysis of large contiguous sequences produced from the bread wheat genome. It provides novel insights into the number, distribution, and density of genes along chromosome 3B and reveals an unexpectedly high amount of noncollinear genes compared to model grass genomes.