Takeo Sato

Plants are able to sense and respond to changes in the balance between carbon (C) and nitrogen (N) metabolite availability, known as the C/N response. During the transition to photoautotrophic growth following germination, growth of seedlings is arrested if a high external C/N ratio is detected. To clarify the mechanisms for C/N sensing and signaling during this transition period, we screened a large collection of FOX transgenic plants, overexpressing full-length cDNAs, for individuals able to c

The balance between carbon (C) and nitrogen (N) availability is an important determinant for various phases of plant growth; however, the detailed mechanisms regulating the C/N response are not well understood. We previously described two related ubiquitin ligases, ATL31 and ATL6, that function in the C/N response in Arabidopsis thaliana. Here, we used FLAG tag affinity purification and MS analysis to identify proteins targeted by ATL31, and thus likely to be involved in regulating the phase tra

Nitrogen (N) is an essential nutrient that affects multiple plant developmental processes, including flowering. As flowering requires resources to develop sink tissues for reproduction, nutrient availability is tightly linked to this process. Low N levels accelerate floral transition; however, the molecular mechanisms underlying this response are not well understood. Here, we identify the FLOWERING BHLH 4 (FBH4) transcription factor as a key regulator of N-responsive flowering in <i>Arabidopsis<

Nutrient availability, in particular the availability of sugar [carbon (C)] and nitrogen (N), is important for the regulation of plant metabolism and development. In addition to independent utilization of C and N nutrients, plants sense and respond to the balance of C and N nutrients (C/N-nutrient) available to them. High C/low N-nutrient stress has been shown to arrest early post-germinative growth while promoting progression to senescence in Arabidopsis. Although several signaling components o

The ubiquitin-proteasome system (UPS) is a unique protein degradation mechanism conserved in the eukaryotic cell. In addition to the control of protein quality, UPS regulates diverse cellular signal transduction via the fine-tuning of target protein degradation. Protein ubiquitylation and subsequent degradation by the 26S proteasome are involved in almost all aspects of plant growth and development and response to biotic and abiotic stresses. Recent studies reveal that the UPS plays an essential

Ubiquitination is a post-translational modification involving the reversible attachment of the small protein ubiquitin to a target protein. Ubiquitination is involved in numerous cellular processes, including the membrane trafficking of cargo proteins. However, the ubiquitination of the trafficking machinery components and their involvement in environmental responses are not well understood. Here, we report that the Arabidopsis thaliana trans-Golgi network/early endosome localized SNARE (soluble

Elevated atmospheric CO₂ concentration is a serious global environmental problem. Elevated CO₂ affects plant growth by changing primary metabolism, closely related to carbon (C) and nitrogen (N) availability. Under sufficient N conditions, plant growth is dramatically promoted by elevated CO₂. When N availability is limited, however, elevated CO₂ disrupts the balance between cellular C and N (C/N). Disruption of the C/N balance is regarded as an important factor in plant growth defects. Here we

SummaryThe Asiatic hybrid lily cultivar ‘Akita Petit White’ (APW) is male-sterile with antherless stamens. This trait is advantageous for florists, who otherwise have to remove anthers carefully after the flowers have bloomed. However, unexpectedly, we observed one or two stamens with intact anthers in a few flowers, on fewer than 1% of a total of 400 plants in a field trial of this cultivar, in a horticultural setting. The trial was performed with bulbs that had been stored at –2°C for 9 months

Due to their immobility, plants have developed sophisticated mechanisms to robustly monitor and appropriately respond to dynamic changes in nutrient availability. Carbon (C) and nitrogen (N) are especially important in regulating plant metabolism and development, thereby affecting crop productivity. In addition to their independent utilization, the ratio of C to N metabolites in the cell, referred to as the "C/N balance", is important for the regulation of plant growth, although molecular mechan

The ubiquitin-26S proteasome system (UPS) plays a crucial role in selective removal of short-lived target proteins, archiving fine-tuning of post-translation levels of the target proteins. Recently a number of ubiquitin ligases (E3) have been reported as essential regulators of various plant developmental cues and stress responses. To clarify the detailed biochemical and physiological function of the E3 proteins, identification of their target proteins is of great importance. A transient express

Abstract In nature, plants cope with various pathogens that compete for cellular resources during infection. It has long been suggested that plant defense activity must be linked to cellular energy and metabolic states to optimize the balance between growth and defense. However, the molecular mechanisms that regulate immune activity in relation to cellular energy status remain unclear. Here, we demonstrate that the plant energy sensor SNF1-RELATED KINASE 1 (SnRK1) plays a critical role in modula