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Polarity-assisting pseudohalide-controlled self-assembly of coordination polymers (CPs) is of immense significance for structural tunability and is quite necessary for exploration of the links between structure and properties. Herein, we have synthesized two polarity-assisting pseudohalide-controlled CPs, CPCd-1and CPCd-2({[(Cd2(L1)3(NCS)4].CHCl3.CH3CN}nand {[Cd(L1)2(N(CN)2)2].CH3CN}n) using newly developed heteroaldazine-based ligand, L1 (L1 = 1-(Z-(Z-(quinolin-4-ylmethylene) hydrazono) methyl) naphthalen-2-ol) at room temperature and systematically characterized through single-crystal X-ray diffraction (SC-XRD) methodology. Interestingly, strong and continuous π···π intermolecular interactions influence both CPs to ensure high luminescence properties in the solvent medium and in the solid phase. Further, these luminous CPs have been utilized for discriminating recognition of the lethal explosive 2,4,6-trinitrophenol (TNP). Notably, CPCd-2shows a lower detection limit (193 ppb) toward TNP detection than CPCd-1(the detection limit is 401 ppb), which is also confirmed by the theoretical scenario. In addition, the sensing mechanism is established via PET-ICT-π···π interaction pathways. Both CPs have numerous practical applications and have been ascertained as innovative ones in environmental domains. This type of pseudohalide-controlled CPs with quinoline-napthaldehyde heteroaldazine-based moieties is scanty in the literature that can detect TNP entirely from the aqueous phase.

The famous Mexican proverb says “They tried to bury us, they did not know we were seeds”. Seeds buried under the soil find their way through the soil particles and emerge out. The mechanical pressure of the soil cover induces the production of the gaseous hormone ethylene in plants. Ethylene promotes formation of an apical hook to protect the plant tip when seedlings try to penetrate through the soil. The dark environment under the soil cover also promotes apical hook formation. Once the seedlings reach the soil surface the apical hook opens to expose the meristem and initiate the development of aerial parts. Recent studies suggest the integration of the ethylene and light signaling pathway to regulate soil emergence. Here we summarize our current understanding of how light and ethylene signals coordinate to optimize seedling establishment. This might contribute towards crop improvement programs as successful emergence is critical for survival of seeds plants in natural environments and agricultural fields.

Almost half of the world’s arable land has acidic pH. Aluminum salts present in acid soils dissociate to release Al3+ions in the soil solution that inhibit root growth causing severe loss in crop yields. Aluminium toxicity accounts for the second highest loss in plant productivity after drought. Aluminium in high doses causes damage to the plant cell wall, cytoskeleton and DNA. One of the ways by which plants alleviate aluminium toxicity is by the exudation of citrate from the roots that chelates the free Al3+and prevents its entry into the plant. In several crop plants Multidrug and Toxic Compound Extrusion (MATE) transporters regulate citrate exudation from the roots. The MATE proteins are ubiquitously present in bacteria, archaea, fungi, animals and plants. The origin and evolution of these membrane transporters in plants is not well known. Here, using protein sequence information we identify MATE transporters in major groups of land plants and their algal ancestors. Our study indicates that the MATE family members expanded in number and functionally diverse among the land plants. We also identify motifs present across the streptophyte clade and a conserved aspartate residue that might regulate citrate exudation. This study can provide leads to engineer MATE transporters to confer enhanced tolerance in acid soils.

Objectives: Children with Down syndrome are known to have reduced focusing ability for near vision (hypoaccommodation). Through a vision screening study we investigated the correlation between hypoaccommodation and near visual acuity in individuals with Down syndrome. Methods: A cross-sectional vision screening study was conducted on individuals with Down Syndrome. The screening was done in 4 city schools and 1 screening was conducted as a part of the Special Olympics Bharat program. In addition to the conventional vision screening tests, Nott dynamic retinoscopy was also performed. Both adults and children (age < 18 years) were included. Results: A total of 55 participants (33 children: age 6 to 17 years, 22 adults: age 18 to 41 years) with Down syndrome were screened. Twenty-two participants had visual impairment. Accommodative accuracy was assessed in 29 children and 13 adults. Accommodative lag ( ≥1.00D) was present in 12 children (41.37%) and 7 adults (53.84%). No correlation was found between the lag of accommodation and near visual acuity (ρSpearman= 0.15, p= 0.54). LogMAR near visual acuity was inversely correlated (ρSpearman= −0.841, p< 0.001) to the near viewing distance. Conclusion: Near visual acuity by itself is not a sensitive indicator of accommodative dysfunction. In addition, a closer viewing distance may not indicate adequate amplitude of accommodation. These findings strongly suggest the need for including dynamic retinoscopy in the clinical practice while examining individuals with Down syndrome.

ABSTRACTPhotomorphogenesis is an important developmental process that helps the seedlings adapt to external light conditions. B-Box proteins are a family of transcription factors that regulate photomorphogenic responses. BBX31 negatively regulates photomorphogenesis under visible light. In contrast, it promotes photomorphogenesis under UV-B and enhances tolerance to high doses of UV-B radiation. BBX31 and HY5 independently and oppositely regulate the ability of seedlings to adapt to varying light intensities. BBX31 also regulates primary root elongation under low intensities of white light. GC-MS and HPLC-based metabolite profiling identified differential accumulation of multiple primary and secondary metabolites in 35S:BBX31that might enhance tolerance to UV-B.

ABSTRACTBBX proteins are a family of zinc finger transcription factors that are versatile regulators of plant development. The 32 BBX proteins in Arabidopsis are subdivided into five structural groups based on their domain structure. Members of group IV play important and diverse roles in light-regulated development. The N-terminal B-box domains mediate DNA binding and transcriptional regulation. The C-terminal region determines the functional diversity of the structurally similar group IV members as reported in our recent study investigating the basis of functional diversification between BBX21 and BBX24. We also found that multi-layered regulation of HY5 by the BBX proteins leads to a diverse repertoire of developmental effects. Here we provide a comprehensive structure-function analysis of the group IV BBX proteins.

Recently we reported the identification of a novel B-box transcription factor SALT TOLERANCE HOMOLOG 2 (STH2) that interacts genetically with two key regulators of the light-signaling pathway, HY5 and COP1. We also provided phenotypic and genetic characterization of the sth2mutant suggesting that STH2plays a positive role in regulating photomorphogenesis both independently or together with HY5. Functional assays in protoplasts revealed that STH2 could act as a transcriptional activator. To our knowledge this is the first report of a B-box domain containing protein playing a direct role in activating transcription in plants. Here we discuss the possible position of STH2 in the transcriptional network and comment on the role of the B-box domain in plants.

Cell size is determined by the duration and rate of growth and plays a central role in cell function. Root hairs are tip-growing cellular projections that emerge from the root epidermis and explore the soil to acquire nutrients and water1. Previously we demonstrated that the basic helix–loop–helix transcription factor root hair defective 6-like 4 (RSL4) is necessary and sufficient for root hair growth2. Here we show that RSL4 is synthesized in a 4-h pulse at the initiation of hair elongation and is gradually degraded by the 26S proteasome. The amount of RSL4 synthesis during this pulse is modulated as part of a root hair growth response to low phosphate. RSL4 synthesis increases in low phosphate and this increase prolongs the growth phase, resulting in the development of long root hairs. Our data demonstrate that the amount of RSL4 synthesized during the pulse directly determines the final size of the differentiated root hair cell. We propose that the modulation of growth-promoting transcription factors by external cues could be a general mechanism for the regulation of cell growth by environmental factors during development.