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Water pollution is one of the most critical issues worldwide and is a priority in all scientific agendas. Green nanotechnology presents a plethora of promising avenues for wastewater treatment. This review discusses the current trends in the valorization of zero-cost, biodegradable, and readily available agro-industrial biowaste to produce green bio-nanocatalysts and bio-nanosorbents for wastewater treatment. The promising roles of green bio-nanocatalysts and bio-nanosorbents in removing organic and inorganic water contaminants are discussed. The potent antimicrobial activity of bio-derived nanodisinfectants against water-borne pathogenic microbes is reviewed. The bioactive molecules involved in the chelation and tailoring of green synthesized nanomaterials are highlighted along with the mechanisms involved. Furthermore, this review emphasizes how the valorization of agro-industrial biowaste to green nanomaterials for wastewater treatment adheres to the fundamental principles of green chemistry, circular economy, nexus thinking, and zero-waste manufacturing. The potential economic, environmental, and health impacts of valorizing agro-industrial biowaste to green nanomaterials are highlighted. The challenges and future outlooks for the management of agro-industrial biowaste and safe application of green nanomaterials for wastewater treatment are summarized. [Display omitted] • Synthesis of bio-nanosorbents, bio-nanocatalysts, and bio-nanodisinfectants. • Green synthesized NMs are promising candidates for wastewater treatment. • Valorization of agro-industrial biowaste approaches green chemistry and circular economy. • Ago-industrial biowaste contains a variety of biomolecules that mediate assembly of NMs. • Economic, environmental, and health impacts of valorizing agro-industrial biowaste to green NMs. [ABSTRACT FROM AUTHOR]

Novel subfamily members of deubiquitinating enzyme gene, DUB-1 and DUB-2, are known to be immediate-early genes and are specifically expressed in B-lymphocytes and T-lymphocytes, respectively. Recently, another deubiquitinating enzyme gene DUB-2A, expressed also in T-lymphocytes, has been isolated and we, in this study, found that Dub-2A has isopeptidase activity and there are at least 4 conserved amino acids (Cys60, Asp133, His298, and His307) that are required for catalytic activity of the enzyme. Interestingly, the conserved Asp323 was not essential for the catalytic activity. In addition, transcriptional reporter assay showed that an Ets site and 2 AP-1 sites in the enhancer domain of this gene are required for cytokine inducibility. Taken all together, these results will be very helpful in designing activators or inhibitors of this enzyme in order to regulate its expression and catalytic activity in T-lymphocytes. [Copyright &y& Elsevier]

α-synuclein is one of the proteins involved in degenerative neuronal diseases such as Parkinson's disease (PD) or Lewy body dementia (LBD). The pathogenesis is imparted by the abnormal accumulation of α-synuclein resulting in the formation of a Lewy body (LB) and exerting neurotoxicity via an unknown mechanism. Regulation of α-synuclein is achieved by the ubiquitin-proteasome system (UPS), which influences protein homeostasis via inducing proteasome-dependent degradation by attaching a small molecule (ubiquitin) to the substrate. Deubiquitinating enzymes (DUBs) control the UPS by cleaving the peptide or isopeptide bond between ubiquitin and its substrate proteins. In a previous study, we found that YOD1 deubiquitinates and regulates the cellular function of neural precursor cell expressed developmentally down-regulated protein 4 (NEDD4), an E3 ligase that induces α-synuclein degradation. We hypothesized that YOD1 acts as a DUB involved in a modulated pathway of α-synuclein. In the current study, we found that YOD1 directly interacts with α-synuclein and deubiquitinates K6-, K11-, K29-, K33-, and K63-linked polyubiquitin chains on α-synuclein. Furthermore, YOD1 destabilizes α-synuclein protein stability by upregulating NEDD4. Collectively, this suggests the possibility that YOD1 is potentially a new regulator in the NEDD4-α-synuclein pathway. • α-synuclein is regulated by ubiquitin-proteasome system. • YOD1 binds to and deubiquitinates α-synuclein. • YOD1 decreases protein stability of α-synuclein by stabilizing NEDD4. [ABSTRACT FROM AUTHOR]

Abstract: We have recently identified mammalian homologues of lethal giant larvae (Lgl) tumor suppressor gene, rat Rgl-1 and bovine Bgl-1, and demonstrated that they can complement yeast double mutants lacking Sop1 and Sop2, yeast homologues of Lgl. These gene products are capable of regulating cellular viability in restrictive salt and temperature environments. Since Lgl family members contain the WD-40 repeat motif, we investigated its cellular functions using mouse homologue Mgl-1 in the absence of Sop1 and Sop2 in yeasts by complementation. Interestingly, mutant forms of Mgl-1 at the conserved glycine at position 450 and aspartic acid at position 453 in the most conserved WD-40 repeat motif were not able to complement, indicating that these amino acids are critical for regulating salt tolerance and temperature sensitivity in yeast. These results shed light on the important regulation of cytoskeletal complex for cellular polarity within eukaryotic cells. [Copyright &y& Elsevier]

NANOG, one of homeobox proteins, plays a crucial role in regulating self-renewal and pluripotency for embryonic stem cells (ESCs). Since the ubiquitin-mediated degradation of NANOG protein has been implicated in its cellular functions involved in not only maintenance of pluripotency and pluripotent epiblast, but also prevention of primitive endoderm differentiation, the identification of ubiquitin ligases and deubiquitinating enzymes (DUBs) for NANOG is required to elucidate its protein stability and the regulation of cellular functions in these processes. In this study, we have identified a novel deubiquitinating enzyme USP21 which interacts with NANOG by both yeast two hybrid screening for DUBs and immunoprecipitation analyses. These analyses revealed that USP21 specifically regulates the Lys48-linked polyubiquitination and stability of NANOG, providing a new way of maintaining the pluripotency of ESCs and induced pluripotent stem cells (iPSCs). [ABSTRACT FROM AUTHOR]

Highlights: [•] Klf4 undergoes the 26S proteasomal degradation by ubiquitination on its multiple lysine residues. [•] Essential Klf4 ubiquitination sites are accumulated between 190–263 amino acids. [•] A mutation of lysine at 232 on Klf4 elongates protein turnover. [•] Klf4 mutants dramatically suppress p53 expression both under normal and UV irradiated conditions. [Copyright &y& Elsevier]

Abstract: Sirt2 is a mammalian member of the Sirtuin family of NAD+ (nicotinamide adenine dinucleotide)-dependent protein deacetylases. Although Sir-2.1 (a Caenorhabditis elegans Sirt2 ortholog) has been reported to interact with PAR-5/FTT-2 (a C. elegans 14-3-3 homolog), the molecular significance of the interaction between Sirt2 and 14-3-3 proteins in mammalian cell is not understood. Here, we report that Sirt2 interacts with 14-3-3 β and γ among various 14-3-3 isoforms, and that this interaction is strengthened by AKT. Furthermore, Sirt2 deacetylates and down-regulates the transcriptional activity of p53, and 14-3-3 β/γ augment deacetylation and down-regulation of the p53 transcriptional activity by Sirt2 in an AKT-dependent manner. Treatment of cells with nicotinamide, an inhibitor of Sirtuins, relieves the inhibition of p53 by Sirt2 and 14-3-3 β/γ. Therefore, our results suggest that the interaction between Sirt2 and 14-3-3 β/γ is a novel mechanism for the negative regulation of p53 beside the well-characterized Mdm2-mediated repression. [Copyright &y& Elsevier]

Abstract: Objectives.: To gain a better understanding of the genes involved in the pathogenesis of gestational trophoblastic diseases, we evaluated the genome-wide expression levels of genes in complete hydatidiform mole (H-mole) as compared to normal placenta using cDNA microarray technique. Methods.: The expression profiles of complete H-mole tissues were compared with those of normal placenta using cDNA microarray technique. The data obtained from 10,305 human genes were normalized by the print-tip-based LOWESS method. Significance analysis of microarray (SAM) was used to identify genes with statistically significant changes in expression. The expression levels of genes which showed significant differences between normal early placenta and complete H-mole tissues were further confirmed by RT-PCR. Results.: A cDNA microarray analysis consisting of 10,305 human genes revealed significant changes in the expression of 213 genes, with 91 genes being upregulated and 122 being downregulated. SAM revealed significant changes in gene expression, including those associated with signal transduction, cell structure, transcription, and apoptosis. Further RT-PCR analysis of altered gene expression in mole tissues supported the microarray analysis results. We confirmed the upregulation of TLE4, CAPZA1, PRSS25, RNF130, and USP1 in complete H-mole tissues. Moreover, our study provides the first evidence that ELK3, LAMA3, LNK, STAT2, and TNFRSF25 are downregulated in complete H-mole compared to normal early placenta tissues. Conclusions.: These findings provide a large body of information regarding gene expression profiles associated with complete H-mole tumorigenesis and allow the identification of potential targets for tumor prevention or therapy. [Copyright &y& Elsevier]

Abstract: The ubiquitin-mediated protein degradation pathway has been emphasized for the regulation of numerous cellular mechanisms and the significance of deubiquitination, mediated by deubiquitinating (DUB) enzymes, has been emerging as an essential regulatory step to control these cellular mechanisms. Previously, we demonstrated a human DUB enzyme, HeLa DUB-1, expressed in human ovarian cancer cells. Here, we report human USP36, which has the extension of the C-terminal region of HeLa DUB-1 and has conserved amino acid domains as previously shown in other DUBs. Human USP36, encoding a DUB enzyme, was isolated from ovarian cancer cells using RT-PCR and characterized. We identified DUB enzyme activity of USP36 by analyzing its capability to cleave the ubiquitin. Interestingly, structural and immunoprecipitation analyses revealed for the first time that USP36 contains the PEST motif and is polyubiquitinated. [Copyright &y& Elsevier]