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Summary: The phytohormone abscisic acid (ABA) functions in the control of plant stress responses, particularly in drought stress. A significant mechanism in attenuating and terminating ABA signals involves regulated protein turnover, with certain ABA receptors, despite their main presence in the cytosol and nucleus, subjected to vacuolar degradation via the Endosomal Sorting Complex Required for Transport (ESCRT) machinery.Collectively our findings show that discrete TOM1‐LIKE (TOL) proteins, which are functional ESCRT‐0 complex substitutes in plants, affect the trafficking for degradation of core components of the ABA signaling and transport machinery.TOL2,3,5 and 6 modulate ABA signaling where they function additively in degradation of ubiquitinated ABA receptors and transporters.TOLs colocalize with their cargo in different endocytic compartments in the root epidermis and in guard cells of stomata, where they potentially function in ABA‐controlled stomatal aperture.Although the tol2/3/5/6 quadruple mutant plant line is significantly more drought‐tolerant and has a higher ABA sensitivity than control plant lines, it has no obvious growth or development phenotype under standard conditions, making the TOL genes ideal candidates for engineering to improved plant performance. [ABSTRACT FROM AUTHOR]

This paper aimed to discuss the areal extent and spatial structure of neighborhood, called tol, which possibly demarcate urban tissue with respect to worship of the deity and funerary acts. Bhaktapur is known as one of the historical cities of the World Heritage Site in Kathmandu Valley. The analysis firstly focuses on the dwelling distributions that have the common votary area of the guardian deities' temples/shrines and the use of the same crossing for funerary acts. Then, the authors compare those dwelling distribution with the areal extent of tols to find out how tol boundaries were formed. This result will be a precondition to conduct further examination on historical urban formation in the coming paper. [ABSTRACT FROM AUTHOR]

The Tol system is a five-protein assembly parasitized by colicins and bacteriophages that helps stabilize the Gram-negative outer membrane (OM). We show that allosteric signalling through the six-bladed β-propeller protein TolB is central to Tol function in Escherichia coli and that this is subverted by colicins such as ColE9 to initiate their OM translocation. Protein–protein interactions with the TolB β-propeller govern two conformational states that are adopted by the distal N-terminal 12 residues of TolB that bind TolA in the inner membrane. ColE9 promotes disorder of this ‘TolA box’ and recruitment of TolA. In contrast to ColE9, binding of the OM lipoprotein Pal to the same site induces conformational changes that sequester the TolA box to the TolB surface in which it exhibits little or no TolA binding. Our data suggest that Pal is an OFF switch for the Tol assembly, whereas colicins promote an ON state even though mimicking Pal. Comparison of the TolB mechanism to that of vertebrate guanine nucleotide exchange factor RCC1 suggests that allosteric signalling may be more prevalent in β-propeller proteins than currently realized. [ABSTRACT FROM AUTHOR]

The tol-pal genes play important roles in maintaining outer membrane integrity, transmembrane transportation, and cell division in Gram-negative bacteria. In Pseudomonas aeruginosa, an important human opportunistic pathogen, the tol-oprL genes are organized uniquely in three operons, orf1- tolQRA, tolB and oprL- orf2, and are regulated by iron availability. Similarity between TolQRA and the iron transport system ExbBD-TonB also exists in P. aeruginosa and they can replace each other imperfectly. It is of importance to investigate the regulation and functions of this membrane complex. In the present study, we characterized the promoters and expression profiles of the orf1- tolQRA operon and investigated the function of Orf1. Primer extension was carried out by using both isotope-labeled and florescence labeled primers and the expression profiles were determined using both lacZ and luxCDABE-based transcriptional fusions. Our results revealed two distinct promoters at the upstream region of tolQRA; the one located in front of orf1 was constitutive whereas the other within the orf1 coding region was iron regulated. Expression profiles indicate the tol genes were also downregulated by the quorum-sensing systems during the late stage of growth. Unlike tolQ and tolA, we were able to construct a viable orf1 knockout strain, and the mutant exhibited altered cell and colony morphology, providing first evidence that Orf1 plays a non-essential role in the Tol-OprL complex in P. aeruginosa. [ABSTRACT FROM AUTHOR]

The sequence elements determining the binding of the σ54-containing RNA polymerase (σ54-RNAP) to the Pu promoter of Pseudomonas putida have been examined. Contrary to previous results in related systems, we show that the integration host factor (IHF) binding stimulates the recruitment of the enzyme to the −12/−24 sequence motifs. Such a recruitment, which is fully independent of the activator of the system, XylR, requires the interaction of the C-terminal domain of the α subunit of RNAP with specific DNA sequences upstream of the IHF site which are reminiscent of the UP elements in σ70 promoters. Our data show that this interaction is mainly brought about by the distinct geometry of the promoter region caused by IHF binding and the ensuing DNA bending. These results support the view that binding of σ54-RNAP to a promoter is a step that can be subjected to regulation by factors (e.g. IHF) other than the sole intrinsic affinity of σ54-RNAP for the −12/−24 site. [ABSTRACT FROM AUTHOR]

A novel vertical field plate (VFP) structure with low specific on‐resistance (Ron,sp) is proposed. The VFP is inserted in the field oxide of the drift region with heavily doped N pillar parallel to the trench oxide layer (TOL), which depletes fully the drift region to decrease Ron,sp effectively and enhances the bulk field (ENBULF). The VFP optimises the bulk electric field to increase the breakdown voltage (BV). The BV of VFP is 668 V with an Ron,sp of 44.7 mΩ cm2, which is much lower than the silicon limit. [ABSTRACT FROM AUTHOR]