Suppressor of Cytokine Signaling 2 Regulates Retinal Pigment Epithelium Metabolism by Enhancing Autophagy.

Retinal pigment epithelium (RPE) serves critical functions in maintaining retinal homeostasis. An important function of RPE is to degrade the photoreceptor outer segment fragments daily to maintain photoreceptor function and longevity throughout life. An impairment of RPE functions such as metabolic regulation leads to the development of age-related macular degeneration (AMD) and inherited retinal degenerative diseases. As substrate recognition subunit of a ubiquitin ligase complex, suppressor of cytokine signaling 2 (SOCS2) specifically binds to the substrates for ubiquitination and negatively regulates growth hormone signaling. Herein, we explore the role of SOCS2 in the metabolic regulation of autophagy in the RPE cells. SOCS2 knockout mice exhibited the irregular morphological deposits between the RPE and Bruch's membrane. Both in vivo and in vitro experiments showed that RPE cells lacking SOCS2 displayed impaired autophagy, which could be recovered by re-expressing SOCS2. SOCS2 recognizes the ubiquitylated proteins and participates in the formation of autolysosome by binding with autophagy receptors and lysosome-associated membrane protein2 (LAMP-2), thereby regulating the phosphorylation of glycogen synthase kinase 3ß (GSK3ß) and mammalian target of rapamycin (mTOR) during the autophagy process. Our results imply that SOCS2 participates in ubiquitin-autophagy-lysosomal pathway and enhances autophagy by regulating GSK3ß and mTOR. This study provides a potential therapeutic target for AMD.

Whole transcriptome sequencing identifies key circRNAs, lncRNAs, and miRNAs regulating neurogenesis in developing mouse retina.

BACKGROUND: The molecular complexity of neural retina development remains poorly studied. Knowledge of retinal neurogenesis regulation sheds light on retinal degeneration therapy exploration. Therefore, we integrated the time-series circRNA, lncRNA, miRNA, and mRNA expression profiles of the developing retina through whole-transcriptome sequencing. The key functional ncRNAs and the ceRNA network regulating retinal neurogenesis were identified. RESULTS: Transcriptomic analysis identified circRNA as the most variable ncRNA subtype. We screened a series of neurogenesis-related circRNAs, lncRNAs, and miRNAs using different strategies based on their diversified molecular functions. The expression of circCDYL, circATXN1, circDYM, circPRGRIP, lncRNA Meg3, and lncRNA Vax2os was validated by quantitative real-time PCR. These circRNAs and lncRNAs participate in neurotransmitter transport and multicellular organism growth through the intricate circRNA/lncRNA-miRNA-mRNA network. CONCLUSION: Whole-transcriptome sequencing and bioinformatics analysis systematically screened key ncRNAs in retinal neurogenesis. The validated ncRNAs and their circRNA/lncRNA-miRNA-mRNA network involve neurotransmitter transport and multicellular organism growth during retinal development.

Performance of two species of whiteflies is unaffected by glucosinolate profile in Brassica plants.

BACKGROUND: While plant glucosinolates are known to impart resistance to many insects, their role in the interactions between plants and many phloem-feeding insects such as whiteflies are poorly understood. The whitefly Bemisia tabaci complex comprises many cryptic species that differ in the ability to utilize Brassica plants. However, whether Brassica plants-specific traits such as glucosinolates determine differences of whiteflies in colonizing Brassica plants remains in question. RESULTS: We first observed performance of two whitefly species MEAM1 and Asia II 3, which differ obviously in their ability to colonize Brassica plants, on four cultivars of three Brassica species that vary in glucosinolate profile. We found that the life history characteristics of each of the two whitefly species seems to be only marginally affected by cultivar. We next used wild-type Arabidopsis plants and mutants defective in glucosinolate biosynthesis or hydrolysis to explore the effects of glucosinolates on the whitefly. We found that fecundity and development of immature stages of neither of the two whitefly species differ significantly between wild-type and mutants. CONCLUSION: The data suggest that glucosinolates may have little effect on the oviposition by adults and the survival and development of immature stages of MEAM1 and Asia II 3 whiteflies. The marked differences in colonizing Brassica crops between the two whitefly species are likely due to plant traits other than glucosinolates. © 2021 Society of Chemical Industry.

Molecular cloning, characterization, and promoter analysis of the isochorismate synthase (AaICS1) gene from Artemisia annua.

Isochorismate synthase (ICS) is a crucial enzyme in the salicylic acid (SA) synthesis pathway. The full-length complementary DNA (cDNA) sequence of the ICS gene was isolated from Artemisia annua L. The gene, named AaICS1, contained a 1710-bp open reading frame, which encoded a protein with 570 amino acids. Bioinformatics and comparative study revealed that the polypeptide protein of AaICS1 had high homology with ICSs from other plant species. Southern blot analysis suggested that AaICS1 might be a single-copy gene. Analysis of the 1470-bp promoter of AaICS1 identified distinct cis-acting regulatory elements, including TC-rich repeats, MYB binding site (MBS), and TCA-elements. An analysis of AaICS1 transcript levels in multifarious tissues of A. annua using quantitative real-time polymerase chain reaction (qRT-PCR) showed that old leaves had the highest transcription levels. AaICS1 was up-regulated under wounding, drought, salinity, and SA treatments. This was corroborated by the presence of the predicted cis-acting elements in the promoter region of AaICS1. Overexpressing transgenic plants and RNA interference transgenic lines of AaICS1 were generated and their expression was compared. High-performance liquid chromatography (HPLC) results from leaf tissue of transgenic A. annua showed an increase in artemisinin content in the overexpressing plants. These results confirm that AaICS1 is involved in the isochorismate pathway.

Heterovalent-Doping-Enabled Efficient Dopant Luminescence and Controllable Electronic Impurity Via a New Strategy of Preparing II-VI Nanocrystals.

Substitutional heterovalent doping represents an effective method to control the optical and electronic properties of nanocrystals (NCs). Highly monodisperse II-VI NCs with deep substitutional dopants are presented. The NCs exhibit stable, dominant, and strong dopant fluorescence, and control over n- and p-type electronic impurities is achieved. Large-scale, bottom-up superlattices of the NCs will speed up their application in electronic devices.

[The study of transformation of tobacco with the stress responsible gene BoRS1 from Brassica oleracea var. acephala].

Transgenic tobacco plants expressing a stress responsive gene BoRS1, isolated from Brassica oleracea var. acephala, under the control of the 35S promoter of the Cauliflower mosaic virus were produced. Some plants were further used to test the effect of high level BoRS1 expression on drought stress resistance. The presence of transgene in putative transgenic plants was confirmed by PCR analysis. Thirty-six among 130 transformants showed amplification of predicted fragment of BoRS1 while no amplification was observed in the control. Some transgenic lines confirmed by PCR analysis were analyzed through semi-quantitative one-step RT-PCR for the expression of BoRS1 gene. Amplification of 1.4 kb cDNA product revealed transcription of BoRS1 gene. Meanwhile, differential intensity of the cDNA band indicated variable expression levels of the transgene among different transformed lines. The water loss of detached leaves from the transgenic plants was slower than that of the control. Transgenic tobaccos and the non-transgenic controls were used for further drought stress experiments by using different concentration of mannitol. The transformants showed higher tolerance to drought stress than non-transgenic plants and different transgenic lines exhibited different tolerance during drought stress. These results showed that the BoRS1 gene probably play role in enhancing the ability to drought stress.