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1.
J Basic Microbiol ; 64(1): 119-127, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37562983

RESUMO

The transcription factor (TF)-mediated regulatory network controlling lincomycin production in Streptomyces lincolnensis is yet to be fully elucidated despite several types of associated TFs having been reported. SLCG_2919, a tetracycline repressor (TetR)-type regulator, was the first TF to be characterized outside the lincomycin biosynthetic cluster to directly suppress the lincomycin biosynthesis in S. lincolnensis. In this study, improved genomic systematic evolution of ligands by exponential enrichment (gSELEX), an in vitro technique, was adopted to capture additional SLCG_2919-targeted sequences harboring the promoter regions of SLCG_6675, SLCG_4123-4124, SLCG_6579, and SLCG_0139-0140. The four DNA fragments were confirmed by electrophoretic mobility shift assays (EMSAs). Reverse-transcription quantitative polymerase chain reaction (RT-qPCR) showed that the corresponding target genes SLCG_6675 (anthranilate synthase), SLCG_0139 (LysR family transcriptional regulator), SLCG_0140 (beta-lactamase), SLCG_6579 (cytochrome P450), SLCG_4123 (bifunctional DNA primase/polymerase), and SLCG_4124 (magnesium or magnesium-dependent protein phosphatase) in ΔSLCGL_2919 were differentially increased by 3.3-, 4.2-, 3.2-, 2.5-, 4.6-, and 2.2-fold relative to those in the parental strain S. lincolnensis LCGL. Furthermore, the individual inactivation of these target genes in LCGL reduced the lincomycin yield to varying degrees. This investigation expands on the known DNA targets of SLCG_2919 to control lincomycin production and lays the foundation for improving industrial lincomycin yields via genetic engineering of this regulatory network.


Assuntos
Proteínas de Bactérias , Magnésio , Streptomyces , Magnésio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Antibacterianos , Lincomicina , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tetraciclina , DNA , Regulação Bacteriana da Expressão Gênica
2.
BMC Bioinformatics ; 20(Suppl 25): 688, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31874611

RESUMO

BACKGROUND: The occurrence of cotton pests and diseases has always been an important factor affecting the total cotton production. Cotton has a great dependence on environmental factors during its growth, especially climate change. In recent years, machine learning and especially deep learning methods have been widely used in many fields and have achieved good results. METHODS: First, this papaer used the common Aprioro algorithm to find the association rules between weather factors and the occurrence of cotton pests. Then, in this paper, the problem of predicting the occurrence of pests and diseases is formulated as time series prediction, and an LSTM-based method was developed to solve the problem. RESULTS: The association analysis reveals that moderate temperature, humid air, low wind spreed and rain fall in autumn and winter are more likely to occur cotton pests and diseases. The discovery was then used to predict the occurrence of pests and diseases. Experimental results showed that LSTM performs well on the prediction of occurrence of pests and diseases in cotton fields, and yields the Area Under the Curve (AUC) of 0.97. CONCLUSION: Suitable temperature, humidity, low rainfall, low wind speed, suitable sunshine time and low evaporation are more likely to cause cotton pests and diseases. Based on these associations as well as historical weather and pest records, LSTM network is a good predictor for future pest and disease occurrences. Moreover, compared to the traditional machine learning models (i.e., SVM and Random Forest), the LSTM network performs the best.


Assuntos
Clima , Gossypium/parasitologia , Redes Neurais de Computação , Doenças das Plantas/parasitologia , Área Sob a Curva , Gossypium/crescimento & desenvolvimento , Umidade , Curva ROC , Estações do Ano , Temperatura
3.
FEBS J ; 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39344089

RESUMO

Purine-pyrimidine repeats (PPRs) can form left-handed Z-form DNA and induce DNA double-strand breaks (DSBs), posing a risk for genomic rearrangements and cancer. The zinc finger (ZF) and BTB domain-containing protein 43 (ZBTB43) is a transcription factor containing two Cys2-His2 (C2H2) and one C3H1 zinc fingers and plays a crucial role in maintaining genomic and epigenomic integrity by converting mutagenic Z-form PPRs to the B-form in prospermatogonia. Despite its importance, the molecular mechanism underlying the recognition of PPRs by ZBTB43 remains elusive. In this study, we determined the X-ray crystal structure of the ZBTB43 ZF1-3 in complex with the B-form DNA containing the CA repeats sequence. The structure reveals that ZF1 and ZF2 primarily recognize the CACA sequence through specific hydrogen-bonding and van der Waals contacts via a quadruple center involving Arg389, Met411, His413, and His414. These interactions were further validated by fluorescence-based DNA-binding assays using mutated ZBTB43 variants. Our structural investigation provides valuable insights into the recognition mechanism of PPRs by ZBTB43 and suggests a potential role for ZBTB43 in the transformation of Z-DNA to B-DNA, contributing to the maintenance of genomic stability.

4.
ACS Appl Mater Interfaces ; 16(36): 47348-47356, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39223076

RESUMO

The development of effective multiphoton absorption (MPA) materials for near-infrared (NIR) light-driven photocatalysis holds great significance. In this study, we incorporated two multibranched cyclometallated iridium(III) modules with varying degrees of conjugation onto MPA-inert metal-organic frameworks (MOFs) to active MPA performance. Subsequently, the MOFs were further modified with Co(II) and hyaluronic acid (HA) to fabricate MINCH and MISCH, respectively. By introducing octupolar molecules and expanding the conjugation, MISCH exhibited a larger MPA cross section for efficient NIR light absorption and improved carrier transfer, leading to outstanding NIR light-driven multiphoton photocatalytic hydrogen production. Moreover, the HA modification enabled MISCH to achieve specific multiphoton photocatalytic hydrogen therapy for cancer cells. This study provides valuable insights into constructing highly active MPA materials for NIR light-driven photocatalysis, presenting a potential platform for hydrogen therapy in tumor treatment.

5.
Adv Sci (Weinh) ; : e2405643, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39119878

RESUMO

The construction of near-infrared (NIR) light-activated hydrogen-producing materials that enable the controlled generation and high-concentration release of hydrogen molecules in deep tumor tissues and enhance the effects of hydrogen therapy holds significant scientific importance. To address the key technical challenge of low-efficiency oxidation-reduction reactions for narrow-bandgap photocatalytic materials, this work proposes an innovative approach for the controllable fabrication of multiphoton photocatalytic materials to overcome the limitations imposed by traditional near-infrared photocatalysts with "narrow-bandgap" constraints. Herein, an NIR-responsive multiphoton photocatalyst, ZrTc-Co, is developed by utilizing a post-synthetic coordination modification strategy to introduce hydrogenation active site CoII into a multiphoton responsive MOF (ZrTc). The results reveal that with the introduction of the CoII site, electron-hole recombination can be efficiently suppressed, thus promoting the efficiency of hydrogen evolution reaction. In addition, the integration of CoII can effectively enhance charge transfer and improve static hyperpolarizability, which endows ZrTc-Co with excellent multiphoton absorption. Moreover, hyaluronic acid modification endows ZrTc-Co with cancer cell-specific targeting characteristics, laying the foundation for tumor-specific elimination. Collectively, the proposed findings present a strategy for constructing NIR-II light-mediated hydrogen therapeutic agents for deep tumor elimination.

6.
Front Neurosci ; 17: 1134153, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37034161

RESUMO

Prolonged or excessive exposure to noise can lead to hearing loss, tinnitus and hypersensitivity to sound. The effects of noise exposure on main excitatory and inhibitory neurotransmitter systems in auditory pathway have been extensively investigated. However, little is known about aberrant changes in neuromodulator systems caused by noise exposure. In the current study, we exposed 2-month-old mice to a narrow band noise at 116 dB SPL for 6 h or sham exposure, assessed auditory brainstem responses as well as examined the expression of serotonin reuptake transporter (SERT) in the cochlear nucleus (CN), inferior colliculus (IC), and primary auditory cortex (Au1) using immunohistochemistry. We found that noise exposure resulted in a significant increase in hearing thresholds at 4, 8, 16, 24, and 32 kHz, as well as led to a significant reduction of SERT in dorsal cochlear nucleus (DCN), dorsal IC (ICd), external IC (ICe), and Au1 layers I-IV. This reduction of SERT in these subregions of central auditory system was partially recovered 15 or 30 days after noise exposure. Furthermore, we examined efficacy of resveratrol (RSV) on hearing loss and loss of SERT induced by noise exposure. The results demonstrated that RSV treatment significantly attenuated threshold shifts of auditory brainstem responses and loss of SERT in DCN, ICd, ICe, and Au1 layers I-IV. These findings show that noise exposure can cause hearing loss and subregion-specific loss of SERT in the central auditory system, and RSV treatment could attenuate noise exposure-induced hearing loss and loss of SERT in central auditory system.

7.
Transl Psychiatry ; 8(1): 100, 2018 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-29780165

RESUMO

Recent studies have shown that persistent pain facilitates the response to morphine reward. However, the circuit mechanism underlying this process remains ambiguous. In this study, using chronic constriction injury (CCI) of the sciatic nerve in mice, we found that persistent neuropathic pain reduced the minimum number of morphine conditioning sessions required to induce conditioned place preference (CPP) behavior. This dose of morphine had no effect on the pain threshold. In the medial prefrontal cortex (mPFC), which is involved in both pain and emotion processing, corticotropin-releasing factor (CRF) expressing neuronal activity was increased in CCI mice. Chemogenetic inhibition of mPFC CRF neurons reversed CCI-induced morphine CPP facilitation. Furthermore, the nucleus acumens (NAc) received mPFC CRF functional projections that exerted excitatory effects on NAc neurons. Optogenetic inhibition of mPCF neuronal terminals or local infusion of the CRF receptor 1 (CRFR1) antagonist in the NAc restored the effects of neuropathic pain on morphine-induced CPP behavior, but not in normal mice. On a molecular level, in CCI mice, CRFR1 protein expression was increased in the NAc by a histone dimethyltransferase G9a-mediated epigenetic mechanism. Local G9a knockdown increased the expression of CRFR1 and mimicked CCI-induced hypersensitivity to acquiring morphine CPP. Taken together, these findings demonstrate a previously unknown and specific mPFC CRF engagement of NAc neuronal circuits, the sensitization of which facilitates behavioral responses to morphine reward in neuropathic pain states via CRFR1s.


Assuntos
Hormônio Liberador da Corticotropina/fisiologia , Comportamento de Procura de Droga , Morfina/administração & dosagem , Neuralgia/fisiopatologia , Neurônios/fisiologia , Núcleo Accumbens/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Recompensa , Animais , Condicionamento Clássico , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiopatologia , Neurônios/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , Limiar da Dor , Córtex Pré-Frontal/efeitos dos fármacos
8.
Oncogenesis ; 7(2): 1, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29367650

RESUMO

Homeobox (HOX) genes encode a family of transcription factors, which play crucial roles in numerous processes, and their dysregulation is involved in the carcinogenesis of many human cancers. In the present study, we investigated the roles of HOXC8 in non-small cell lung cancer (NSCLC). We showed that HOXC8 was upregulated in clinical NSCLC specimens compared to normal lung tissues, and the high expression of HOXC8 correlated with tumor node metastasis (TNM) stage, tumor status, lymph nodal status and poor relapse-free survival for lung cancer patients. Functionally, HOXC8 expression significantly promoted the proliferation, anchorage-independent growth and migration of NSCLC, and HOXC8 functioned as a transcription activator to induce the expression of TGFß1, leading to an increase in the proliferation, anchorage-independent growth and migration of NSCLC. Furthermore, we demonstrated that HOXC8 expression was associated with chemoresistance and anti-apoptosis in NSCLC, suggesting that HOXC8 is a promising therapeutic target for chemosensitization of NSCLC to cisplatin. Altogether, our study defined a critical role of HOXC8 in promoting transcription of TGFß1 and NSCLC tumorigenesis.

9.
Oncotarget ; 8(64): 107477-107491, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29296180

RESUMO

Cadherin 11 (CDH11) expression is detected only in invasive breast cancer cells and aggressive breast cancer specimens. However, little is known about the molecular mechanisms of CDH11 transcriptional regulation. Here, we report that interleukin enhancer binding factor 3 (ILF3) interacts with Homeobox C8 (HOXC8) to activate CDH11 transcription in breast cancer cells. Using co-immunoprecipitation and mass spectrometry analyses, ILF3 is shown to interact with HOXC8 in breast cancer cells. We demonstrate that ILF3 binds to the CDH11 promoter on nucleotides -2982 ~ -2978 and -2602 ~ 2598 and interacts with HOXC8 to co-activate CDH11 transcription. We further show that ILF3 promotes proliferation and migration, at least partially, by facilitating CDH11 expression in breast cancer cells. Moreover, immunohistochemistry (IHC) shows that expression of CDH11, ILF3 and HOXC8 are all upregulated in breast cancer specimens compared to normal breast tissues. Importantly, the expression levels of CDH11, ILF3 and HOXC8 are elevated in the advanced stages of breast cancer, and high expression of CDH11, ILF3 and HOXC8 is associated with poor distant metastasis-free survival (DMFS) for breast cancer patients.

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