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BACKGROUND: Endoscopic resection has been reported for vascular anomalies (VA) previously. However, there is no study comparing endoscopic resection surgery (ERS) with open resection surgery (ORS) in children. We aimed to compare clinical and cosmetic outcomes between two approaches in pediatric VA. METHODS: Between June 2018 and June 2023, 138 pediatric VA patients undergoing ERS or ORS were retrospectively reviewed. Propensity score matching (PSM) was performed to minimize selection bias. The Scar Cosmesis Assessment and Rating (SCAR) Scale and numerical rating scale (NRS) based on patient satisfaction were used for cosmetic assessment. RESULTS: After PSM for age, depth of lesion, size of lesion, and site of surgery, 72 patients (ERS = 24, ORS = 48) were analyzed. Patients undergoing ERS had longer operative time (164.25 ± 18.46 vs. 112.85 ± 14.26 min; P < 0.001), less estimated blood loss (5.42 ± 2.15 vs. 18.04 ± 1.62 ml; P < 0.001), and shorter median hospital stay (4.50 [3.00-5.00] vs. 6.00 [5.00-6.00] days; P < 0.001). The follow-up time was 8.04 ± 1.23 month for ERS group and 8.56 ± 1.57 month for ORS group. For aesthetic results, the median overall SCAR score in ERS was lower than that in ORS (2 [1-3] vs. 5 [4-5]; P < 0.001), and the subscales of "scar spread," "dyspigmentation," "track marks or suture marks," and "overall impression" were better. The median NRS score was higher (8 [7-8] vs. 6 [5-6]; P < 0.001) and length of scars was shorter (2.18 ± 0.30 vs. 8.75 ± 1.98 cm; P < 0.001) in ERS group than those in ORS group. The incidences of total complications and recurrence showed no significant difference between two groups. CONCLUSIONS: Endoscopic surgery can be a safe and effective option for pediatric VA in the limbs and trunk. It offers the advantages of improving aesthetic outcomes and reducing postoperative wound healing time.
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The design of stable and variable aryl linkers for conjugating drug moieties to the metabolism-related thiols is of importance in drug discovery. We disclosed that thioimidazolium groups are unique scaffolds for the thiol-(hetero)arene conjugation under mild conditions. The drug bound thioimidazolium salts, which are easily accessible via a copper-mediated Chan-Lam process in gram-scale, could be successfully applied to the late-stage coupling of bioactive thiols to construct a broad array of drug-like molecules.
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PURPOSE: Tyrosine kinase inhibitor (TKI) resistance is the main type of drug resistance in lung cancer patients with epidermal growth factor receptor (EGFR) mutations, but its underlying mechanism remains unclear. The purpose of this work was to investigate the mechanism by which PARP1 regulates EGFR-TKI resistance to identify potential targets for combating drug resistance. METHODS: The GEO databases, TCGA databases, western blot and qPCR studies were used to investigate the expression of PARP1 in lung cancer cells and tissues and its correlation with the prognosis of lung cancer. The expression of PARP1 in lung cancer TKI resistant cell PC9-ER and TKI sensitive cell PC9 was analyzed by qPCR and western blot. After knocking down of PARP1, CCK-8 assays, colony formation, flow cytometry were used to investigate its impact on erlotinib sensitivity, cell survival, cell cycle, and apoptosis. RNA-seq was used to investigate the mechanism by which PARP1 participates in EGFR-TKI resistance, and the results were validated in vitro and in vivo studies. RESULTS: PARP1 was highly expressed in both lung cancer tissues and cells. Subsequently, increased PARP1 expression was observed in PC9-ER compared with its parental cell line. Knockdown of PARP1 increased erlotinib sensitivity, promoted cell apoptosis, and suppressed cell growth. RNA-seq and previous studies have shown that the PI3K/AKT/mTOR/P70S6K pathway is involved in PARP1-mediated TKI resistance, and these results were confirmed by Western blot in vitro and in vivo. CONCLUSION: PARP1 may serve as a potential therapeutic target for reversing EGFR-TKI resistance in NSCLC via the PI3K/AKT/mTOR/P70S6K pathway.
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Phages play a crucial role in orchestrating top-down control within microbial communities, influencing the dynamics of the composting process. Despite this, the impact of phage-induced thermophilic bacterial lysis on humification remains ambiguous. This study investigates the effects of phage lysate, derived explicitly from Geobacillus subterraneus, on simulated composting, employing ultrahigh-resolution mass spectrometry and 16S rRNA sequencing techniques. The results show the significant role of phage lysate in expediting humus formation over 40 days. Notably, the rapid transformation of protein-like precursors released from phage-induced lysis of the host bacterium resulted in a 14.8 % increase in the proportion of lignins/CRAM-like molecules. Furthermore, the phage lysate orchestrated a succession in bacterial communities, leading to the enrichment of core microbes, exemplified by the prevalence of Geobacillus. Through network analysis, it was revealed that these enriched microbes exhibit a capacity to convert protein and lignin into essential building blocks such as amino acids and phenols. Subsequently, these components were polymerized into humus, aligning with the phenol-protein theory. These findings enhance our understanding of the intricate microbial interactions during composting and provide a scientific foundation for developing engineering-ready composting humification regulation technologies.
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Bactériophages , Compostage , ARN ribosomique 16S/génétique , Sol , Bactéries , Phénols/analyse , Lignine , Fumier , Substances humiques/analyseRÉSUMÉ
A highly efficient system incorporates the real-time visualization of the two toxic molecules (H2S and N2H4) and the recognition of corresponding transforms using a fluorescent sensor. In this paper, a dual-responsive probe (QS-DNP) based on methylquinolinium-salicyaldehyde-2,4-dinitrophenyl was developed that can simultaneously detect H2S and N2H4 at two independent fluorescent channels without signal crosstalk. QS-DNP showed excellent anti-interference, high selectivity, outstanding water solubility, low LOD values (H2S: 51 nM; N2H4: 40 nM), low cytotoxicity, and mitochondrial localization properties. The 2,4-dinitrophenyl site was sensitive to H2S, and the CC bridge was reactive to N2H4, with strong fluorescence at 680 and 488 nm, respectively. The wavelength gap between these two channels is 192 nm; verify that there is no signal crosstalk throughout detection. By this means, the probe was used to simultaneously detect H2S and N2H4 in real soil samples, food samples, and living cells. The endogenous H2S and N2H4 were monitored in HeLa cells and investigated the mitochondria organelle of living cells with a positive charge on QS-DNP. Overall, all results emphasize that the QS-DNP probe is a powerful tool for the simultaneous detection of H2S and N2H4 and presents a potential new sensing approach.
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Colorants fluorescents , Hydrazines , Sulfure d'hydrogène , Humains , Cellules HeLa , Mitochondries , Spectrométrie de fluorescenceRÉSUMÉ
Background: Glucose metabolism (GM) plays a crucial role in cancer cell proliferation, tumor growth, and survival. However, the identification of glucose metabolism-related genes (GMRGs) for effective prediction of prognosis in head and neck squamous cell carcinoma (HNSC) is still lacking. Methods: We conducted differential analysis between HNSC and Normal groups to identify differentially expressed genes (DEGs). Key module genes were obtained using weighted gene co-expression network analysis (WGCNA). Intersection analysis of DEGs, GMRGs, and key module genes identified GMRG-DEGs. Univariate and multivariate Cox regression analyses were performed to screen prognostic-associated genes. Independent prognostic analysis of clinical traits and risk scores was implemented using Cox regression. Gene set enrichment analysis (GSEA) was used to explore functional pathways and genes between high- and low-risk groups. Immune infiltration analysis compared immune cells between the two groups in HNSC samples. Drug prediction was performed using the Genomics of Drug Sensitivity in Cancer (GDSC) database. Quantitative real-time fluorescence PCR (qRT-PCR) validated the expression levels of prognosis-related genes in HNSC patients. Results: We identified 4973 DEGs between HNSC and Normal samples. Key gene modules, represented by black and brown module genes, were identified. Intersection analysis revealed 76 GMRG-DEGs. Five prognosis-related genes (MTHFD2, CDKN2A, TPM2, MPZ, and DNMT1) were identified. A nomogram incorporating age, lymph node status (N), and risk score was constructed for survival prediction in HNSC patients. Immune infiltration analysis showed significant differences in five immune cell types (Macrophages M0, memory B cells, Monocytes, Macrophages M2, and Dendritic resting cells) between the high- and low-risk groups. GDSC database analysis identified 53 drugs with remarkable differences between the groups, including A.443654 and AG.014699. DNMT1 and MTHFD2 were up-regulated, while MPZ was down-regulated in HNSC. Conclusion: Our study highlights the significant association of five prognosis-related genes (MTHFD2, CDKN2A, TPM2, MPZ, and DNMT1) with HNSC. These findings provide further evidence of the crucial role of GMRGs in HNSC.
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Métabolisme glucidique , Tumeurs de la tête et du cou , Humains , Pronostic , Carcinome épidermoïde de la tête et du cou/génétique , Tumeurs de la tête et du cou/génétique , GlucoseRÉSUMÉ
Cadmium (Cd) pollution of soil occurs worldwide. Phytoremediation is an effective approach for cleaning up Cd polluted soil. Fast growing Populus species with high Cd uptake capacities are desirable for phytoremediation. Thus, it is important to elucidate the molecular functions of genes involved in Cd uptake by poplars. In this study, PcPLAC8-10, a homolog of Human placenta-specific gene 8 (PLAC8) implicated in Cd transport was functionally characterized in Populus × canescens. PcPLAC8-10 was transcriptionally induced in Cd-treated roots and it encoded a plasma membrane-localized transporter. PcPLAC8-10 exhibited Cd uptake activity when expressed in yeast cells. No difference in growth was observed between wild type (WT) and PcPLAC8-10-overexpressing poplars. PcPLAC8-10-overexpressing poplars exhibited increases in net Cd2+ influxes by 192% and Cd accumulation by 57% in the roots. However, similar reductions in biomass were found in WT and transgenic poplars when exposed to Cd. The complete motif of CCXXXXCPC in PcPLAC8-10 was essential for its Cd transport activity. These results suggest that PcPLAC8-10 is a plasma membrane-localized transporter responsible for Cd uptake in the roots and the complete CCXXXXCPC motif of PcPLAC8-10 plays a key role in its Cd transport activity in poplars.
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Cadmium , Populus , Humains , Populus/génétique , Transport biologique , Transport des ions , Protéines de transport membranaire , Saccharomyces cerevisiae , Sol , ProtéinesRÉSUMÉ
Introduction: As a congenital and genetically related disease, many single nucleotide polymorphisms (SNPs) have been reported to be associated with the risk of HSCR. Our previous research showed that SNP rs2439302 (NRG1) interacted with rs2435357 (RET) to increase the risk of HSCR development. However, the underlying molecular mechanism is still not well understood. Methods: SNP rs2439302 (NRG1) and rs2435357 (RET) were genotyped in 470 HSCR cases. The expression of NRG1 and RET was investigated in the colon of HSCR patients. Knockdown of the NRG1 and RET homologs was performed in zebrafish to investigate their synergistic effect on ENS development. The effect of SNP rs2439302 and rs2435357 polymorphism on neuron proliferation, migration, and differentiation were investigated in SHSY-5Y cells and IPSCs. Results: Significant downregulation of NRG1 and RET expression was noticed in the aganglionic segment of HSCR patients and SHSY-5Y cells with rs2439302 GG/rs2435357 TT genotype. NRG1 and RET double mutants caused the most severe reduction in enteric neuron numbers than NRG1 single mutant or RET single mutant in the hindgut of zebrafish. SHSY-5Y cells and IPSCs with rs2439302 GG/rs2435357 TT genotype exhibited a decreased proliferative, migration, and differentiative capacity. CTCF showed a considerably higher binding ability to SNP rs2439302 CC than GG. NRG1 reduction caused a further decrease in SOX10 expression via the PI3K/Akt pathway, which regulates RET expression by directly binding to rs2435357. Discussion: SNP rs2439302 (NRG1) GG increases the risk of developing HSCR by affecting the binding of transcription factor CTCF and interacting with rs2435357 (RET) to regulate RET expression via the PI3K/Akt/SOX10 pathway.
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The deconstructive ring cleavage of cyclic thioethers is achieved through a Chan-Lam type process with boron compounds. The sequential hydroboration/ring cleavage process from alkynes offered a new route to the preparation of vinyl sulfides based on the developed conditions. Further exploration has demonstrated the versatility of nucleophiles, delivering various functionalized sulfides featuring linear frameworks.
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We propose and experimentally demonstrate a novel FPGA-based parallel architecture for delta-sigma modulation (DSM) for digital mobile fronthaul employing the DSM interface. This architecture breaks the limitations of the feedback loop in DSM, is not constrained by critical paths, and supports fully parallel processing, so it can deal with high sampling rates at low hardware operating speeds. In contrast to other parallel schemes, the proposed bit-by-bit quantization DSM avoid significant storage resources requirements for buffering. A real-time experimental system using Xilinx Kintex Ultrascale FPGA was implemented to validate the feasibility of the proposed architecture. 14 carrier aggregated orthogonal frequency division multiplexing (OFDM) signals are digitized by DSM into a 5Gb/s PAM4 signal and transmitted over a 20â km single-mode fiber (SMF). As a waveform-agnostic digitization interface, we also experimentally demonstrated the DSM with 14 carrier aggregated filter-bank-multicarrier (FBMC) signals, which can achieve better EVM performance.
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Background: Minimal invasive pulmonary resection in children is challenging, irrespective of whether it is conducted using a robot or a thoracoscope. This study presents the preliminary results of pediatric robotic pulmonary resection (RPR) and comparison outcomes with conventional thoracoscopic pulmonary resection (TPR). Methods: This is a retrospective study conducted in patients underwent RPR (RPR group; n=30) and TPR (TPR group; n=44). The clinical data, including operative time, post-operative body temperature, surgical complications, surgeon's workload (by NASA-TLX), postoperative hospital stay, and scar score (using the SCAR scale), of both the RPR and TPR groups were collected and compared. Results: Both groups had similar age and weight. The youngest patient belonged to the RPR group and was 6 months old and weighed 8 kg. One case in the RPR group and two in the TPR group were converted to thoracotomy. RPR had a longer total operative time (148.3±36.8 min), but a shorter pure operative time (103.9±28.5 min) than those of the TPR group [118.3±22.5 (P<0.001) and 111.4±18.3 min (P=0.045), respectively]. Compared to the TPR group, fewer patients in the RPR group reported fever postoperatively (2/29 vs. 11/42, P=0.039). The workload of the surgeons was also lower in the RPR group (55.2±4.7 vs. 62.9±6.0, P<0.01). No significant difference was observed in perioperative complications, drainage length, postoperative hospital stays, and scar score of the two groups. Conclusions: The safety and effectiveness of the robotic approach are similar to those of the thoracoscopic surgery for pediatric pulmonary resection in children heavier than 8 kg. In addition, the robotic approach shows improved operative dissection efficiency and accuracy for patients and reduced workload for surgeons. Hence, it is beneficial to both surgeons and patients.
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Floral initiation is a major phase change in the spermatophyte, where developmental programs switch from vegetative growth to reproductive growth. It is a key phase of flowering in tea-oil trees that can affect flowering time and yield, but very little is known about the molecular mechanism of floral initiation in tea-oil trees. A 12-year-old Camellia oleifera (cultivar 'changlin53') was the source of experimental materials in the current study. Scanning electron microscopy was used to identify the key stage of floral initiation, and transcriptome analysis was used to reveal the transcriptional regulatory network in old leaves involved in floral initiation. We mined 5 DEGs related to energy and 55 DEGs related to plant hormone signal transduction, and we found floral initiation induction required a high level of energy metabolism, and the phytohormones signals in the old leaves regulate floral initiation, which occurred at stage I and II. Twenty-seven rhythm-related DEGs and 107 genes associated with flowering were also identified, and the circadian rhythm interacted with photoperiod pathways to induce floral initiation. Unigene0017292 (PSEUDO-RESPONSE REGULATOR), Unigene0046809 (LATE ELONGATED HYPOCOTYL), Unigene0009932 (GIGANTEA), Unigene0001842 (CONSTANS), and Unigene0084708 (FLOWER LOCUS T) were the key genes in the circadian rhythm-photoperiod regulatory network. In conjunction with morphological observations and transcriptomic analysis, we concluded that the induction of floral initiation by old leaves in C. oleifera 'changlin53' mainly occurred during stages I and II, floral initiation was completed during stage III, and rhythm-photoperiod interactions may be the source of the main signals in floral initiation induced by old leaves.
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Camellia , Camellia/génétique , Camellia/métabolisme , Arbres/génétique , Analyse de profil d'expression de gènes , Fleurs/métabolisme , Feuilles de plante/génétique , Feuilles de plante/métabolisme , Facteur de croissance végétal/métabolisme , Thé/métabolisme , Transcriptome , Régulation de l'expression des gènes végétauxRÉSUMÉ
The NF-YA gene family is a class of conserved transcription factors that play important roles in plant growth and development and the response to abiotic stress. Poplar is a model organism for studying the rapid growth of woody plants that need to consume many nutrients. However, studies on the response of the NF-YA gene family to nitrogen in woody plants are limited. In this study, we conducted a systematic and comprehensive bioinformatic analysis of the NF-YA gene family based on Populus × canescens genomic data. A total of 13 PcNF-YA genes were identified and mapped to 6 chromosomes. According to the amino acid sequence characteristics and genetic structure of the NF-YA domains, the PcNF-YAs were divided into five clades. Gene duplication analysis revealed five pairs of replicated fragments and one pair of tandem duplicates in 13 PcNF-YA genes. The PcNF-YA gene promoter region is rich in different cis-acting regulatory elements, among which MYB and MYC elements are the most abundant. Among the 13 PcNF-YA genes, 9 contained binding sites for P. × canescens miR169s. In addition, RT-qPCR data from the roots, wood, leaves and bark of P. × canescens showed different spatial expression profiles of PcNF-YA genes. Transcriptome data and RT-qPCR analysis showed that the expression of PcNF-YA genes was altered by treatment with different nitrogen forms. Furthermore, the functions of PcNF-YA genes in transgenic poplar were analyzed, and the potential roles of PcNF-YA genes in the response of poplar roots to different nitrogen forms were revealed, indicating that these genes regulate root growth and development.
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Populus , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes végétaux , Gènes de plante , Famille multigénique , Azote/métabolisme , Phylogenèse , Protéines végétales/métabolisme , Populus/métabolisme , Stress physiologique/génétique , Facteurs de transcription/génétique , Facteurs de transcription/métabolismeRÉSUMÉ
In this paper, a modified low-bandwidth sub-Nyquist sampling receiving scheme enabled by optical shaping is investigated in an intensity modulation/direct detection (IM/DD) orthogonal frequency-division multiplexing (OFDM) system, which can reduce the sampling rate and analog bandwidth of an analog-to-digital converter (ADC) at the receiving end. By changing the phase matrix of preprocessing, the modified scheme can distinguish different groups of data only by controlling the delay of the shaping module. In addition, the proposed RF sharing architecture can further reduce the cost and increase the feasibility of the scheme. Based on arcsine digital pre-distortion (DPD) technology, a DPD optical pulse shaping scheme is proposed to achieve better spectrum aliasing in the optical domain. With the help of the DPD shaping, we successfully experimentally demonstrate the 12.5-GHz/44.45-Gbit/s IM/DD OFDM system with low-bandwidth (3.125â GHz) and sub-Nyquist sampling rate (6.25 GSa/s) ADC. The experiment results show that the proposed scheme can not only effectively achieve low-bandwidth reception, but also achieve about 0.4 dB receiver sensitivity improvement compared with the traditional high-bandwidth scheme at BER of 3.8×10-3 after 10.2 km standard single mode fiber transmission, which indicates that the proposed scheme is a promising low-cost candidate to provide large transmission capacity for the next-generation network.
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In this paper, 100 Gb/s/λ 32 quadrature amplitude modulation discrete multi-tone (QAM-DMT) transmission using 10 G-class electro-absorption modulated laser (EML) and 4/5-bit digital-to-analog converters (DACs) are experimentally demonstrated to meet the requirement of intra-datacenter interconnection (intra-DCI). Unequal length multi-band (ULM) discrete Fourier transform spread (DFT-S) precoding is investigated to alleviate the distortion induced by the high peak-to-average power ratio (PAPR) of DMT. The results show that the required computational complexity of ULM DFT-S precoding with 2-bands (k1=256, k2=64) decreases sharply compared to the traditional DFT-S technique with only about 0.5â dB receiver sensitivity penalty. In addition, compared to the equal length multi-band (ELM) DFT-S precoding, the ULM DFT-S precoding can bring about 2.5â dB receiver sensitivity improvement with slight added computational complexity. With the assistance of ULM DFT-S precoding and noise shaping (NS) technique, the bit-error ratio (BER) of 100 Gb/s 32 QAM-DMT signal generated by 5-bit DAC over 2-km single-mode fiber (SMF) transmission can reach the hard-decision forward error correction (HD-FEC) threshold with received optical power (ROP) of -6.5 dBm, with only additional 39.9% multiplier and 33.7% adder.
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In this paper, we propose a novel transceiver in-phase/quadrature (I/Q) skew in-field calibration scheme with correlation-based method for the dual-polarization coherent optical system. Simultaneous dual-polarization calibration of transceiver I/Q skews after fiber transmission is experimentally performed. Rx/Tx correlation-based skew estimations (CBSEs) are proposed to accurately estimate the transceiver I/Q skews with dual-polarization OFDM signal. By simulation, the robustness of the Rx/Tx CBSEs is investigated against various transceiver I/Q imbalances and channel impairments including carrier frequency offset (CFO), phase noise (PN), and chromatic dispersion (CD). The simultaneous measurement of large transceiver skews is studied within a range of ±128 ps. The bit error rate (BER) improvement brought by the CBSEs is studied in 80â km single-mode fiber (SMF) transmissions under various Rx/Tx skews. In the experiments, the Rx/Tx skew is measured in the range of 1 to 128 ps w/ and w/o the presence of 5 ps Tx/Rx skew. Simultaneous dual-polarization measurements are performed with the X/Y polarization Tx/Rx skews set to 2.5 ps, 5 ps, 7.5 ps and 10 ps, respectively. The measurement errors are within ±0.2 ps. The 80â km SMF dual-polarization transmission after in-field calibration for inter-data center interconnection (inter-DCI) is implemented, with a data rate of 400 Gb/s for both 16QAM and 32QAM modulation formats.
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Background: Unlocking phenotype plasticity (UPP) has been shown to have an essential role in the mechanism of tumor development and therapeutic response. However, the clinical significance of unlocking phenotypic plasticity in patients with lung adenocarcinoma is unclear. This study aimed to explore the roles of unlocking phenotypic plasticity in immune status, prognosis, and treatment in patients with lung adenocarcinoma (LUAD). Methods: Differentially expressed genes (DEGs) and clinical information of UPP were selected from the cancer genome atlas (TCGA) database, and the GO, KEGG enrichment analyses were performed. The independent prognostic genes were determined by univariate and multivariate Cox regression, and the UPP signature score was constructed. Patients with LUAD were divided into high- and low-risk groups according to the median of score, and the immunocytes and immune function, the gene mutation, and drug sensitivities between the two groups were analyzed. Finally, the results were validated in the GEO database. Results: Thirty-nine significantly DEGs were determined. Enrichment analysis showed that UPP-related genes were related to protein polysaccharides and drug resistance. The prognostic results showed that the survival of patients in the high-risk group was poorer than that in the low-risk group (p < 0.001). In the high- and low-risk groups, single nucleotide polymorphism (SNP) and C > T are the most common dissent mutations. The contents of immune cells were significantly different between high- and low-risk groups. And the immune functions were also significantly different, indicating that UPP affects the immunity in LUAD. The results from TCGA were validated in the GEO. Conclusion: Our research has proposed a new and reliable prognosis indicator to predict the overall survival. Evaluation of the UPP could help the clinician to predict therapeutic responses and make individualized treatment plans in patients with LUAD.
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Circular RNAs (circRNAs) are a class of noncoding RNA molecules with ring structures formed by covalent bonds and are commonly present in organisms, playing an important regulatory role in plant growth and development. However, the mechanism of circRNAs in poplar root responses to different forms of nitrogen (N) is still unclear. In this study, high-throughput sequencing was used to identify and predict the function of circRNAs in the roots of poplar exposed to three N forms [1 mM NO3 - (T1), 0.5 mM NH4NO3 (T2, control) and 1 mM NH4 + (T3)]. A total of 2,193 circRNAs were identified, and 37, 24 and 45 differentially expressed circRNAs (DECs) were screened in the T1-T2, T3-T2 and T1-T3 comparisons, respectively. In addition, 30 DECs could act as miRNA sponges, and several of them could bind miRNA family members that play key roles in response to different N forms, indicating their important functions in response to N and plant growth and development. Furthermore, we generated a competing endogenous RNA (ceRNA) regulatory network in poplar roots treated with three N forms. DECs could participate in responses to N in poplar roots through the ceRNA regulatory network, which mainly included N metabolism, amino acid metabolism and synthesis, response to NO3 - or NH4 + and remobilization of N. Together, these results provide new insights into the potential role of circRNAs in poplar root responses to different N forms.
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Poplars are proposed for the phytoremediation of heavy metal (HM) polluted soil. Characterization of genes involved in HM uptake and accumulation in poplars is crucial for improving the phytoremediation efficiency. Here, Natural Resistance-Associated Macrophage Protein 1 (NRAMP1) encoding a transporter involved in cadmium (Cd) uptake and transport was functionally characterized in Populus × canescens. Eight putative PcNRAMPs were identified in the poplar genome and most of them were primarily expressed in the roots. The expression of PcNRAMP1 was induced in Cd-exposed roots and it encoded a plasma membrane-localized protein. PcNRAMP1 showed transport activity for Cd2+ when expressed in yeast. The PcNRAMP1-overexpressed poplars enhanced net Cd2+ influxes by 39-52% in the roots and Cd accumulation by 25-29% in aerial parts compared to the wildtype (WT). However, Cd-induced biomass decreases were similar between the transgenics and WT. Further analysis displayed that the two amino acid residues of PcNRAMP1, i.e., M236 and P405, play pivotal roles in regulating its transport activity for Cd2+. These results suggest that PcNRAMP1 is a plasma membrane-localized transporter involved in Cd uptake and transporting Cd from the roots to aerial tissues, and that the conserved residues in PcNRAMP1 are essential for its Cd transport activity in poplars.
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Populus , Polluants du sol , Dépollution biologique de l'environnement , Transport biologique/génétique , Cadmium/métabolisme , Racines de plante/génétique , Racines de plante/métabolisme , Populus/métabolisme , Polluants du sol/métabolismeRÉSUMÉ
Nitrate (NO3 -) and ammonium (NH4 +) are the primary forms of inorganic nitrogen acquired by plant roots. LncRNAs, as key regulators of gene expression, are a class of non-coding RNAs larger than 200 bp. However, knowledge about the regulatory role of lncRNAs in response to different nitrogen forms remains limited, particularly in woody plants. Here, we performed strand-specific RNA-sequencing of P. × canescens roots under three different nitrogen fertilization treatments. In total, 324 lncRNAs and 6,112 mRNAs were identified as showing significantly differential expression between the NO3 - and NH4NO3 treatments. Moreover, 333 lncRNAs and 6,007 mRNAs showed significantly differential expression between the NH4 + and NH4NO3 treatments. Further analysis suggested that these lncRNAs and mRNAs have different response mechanisms for different nitrogen forms. In addition, functional annotation of cis and trans target mRNAs of differentially expressed lncRNAs indicated that 60 lncRNAs corresponding to 49 differentially expressed cis and trans target mRNAs were involved in plant nitrogen metabolism and amino acid biosynthesis and metabolism. Furthermore, 42 lncRNAs were identified as putative precursors of 63 miRNAs, and 28 differentially expressed lncRNAs were potential endogenous target mimics targeted by 96 miRNAs. Moreover, ceRNA regulation networks were constructed. MSTRG.6097.1, MSTRG.13550.1, MSTRG.2693.1, and MSTRG.12899.1, as hub lncRNAs in the ceRNA networks, are potential candidate lncRNAs for studying the regulatory mechanism in poplar roots under different nitrogen fertilization treatments. The results provide a basis for obtaining insight into the molecular mechanisms of lncRNA responses to different nitrogen forms in woody plants.