Stable peptide-assembled nanozyme mimicking dual antifungal actions.

Natural antimicrobial peptides (AMPs) and enzymes (AMEs) are promising non-antibiotic candidates against antimicrobial resistance but suffer from low efficiency and poor stability. Here, we develop peptide nanozymes which mimic the mode of action of AMPs and AMEs through de novo design and peptide assembly. Through modelling a minimal building block of IHIHICI is proposed by combining critical amino acids in AMPs and AMEs and hydrophobic isoleucine to conduct assembly. Experimental validations reveal that IHIHICI assemble into helical ß-sheet nanotubes with acetate modulation and perform phospholipase C-like and peroxidase-like activities with Ni coordination, demonstrating high thermostability and resistance to enzymatic degradation. The assembled nanotubes demonstrate cascade antifungal actions including outer mannan docking, wall disruption, lipid peroxidation and subsequent ferroptotic death, synergistically killing >90% Candida albicans within 10 min on disinfection pad. These findings demonstrate an effective de novo design strategy for developing materials with multi-antimicrobial mode of actions.

Global left ventricular myocardial work: A novel method to assess left ventricular myocardial function and predict major adverse cardiovascular events in maintenance hemodialysis patients.

BACKGROUND: The application value of myocardial work (MW) in evaluating myocardial function and predicting major adverse cardiovascular events (MACE) in maintenance hemodialysis (MHD) patients has not been fully explored. PURPOSE: Comparing noninvasive MW parameters between MHD patients and healthy controls, and further determining its value in predicting MACE in MHD patients. METHODS: A prospective single-institution study included 92 MHD patients without prior cardiovascular disease and 40 age- and sex-matched healthy controls. Conventional echocardiographic data, global longitudinal strain (GLS), and MW parameters (global work index [GWI], global constructive work [GCW], global work efficiency [GWE], global wasted work [GWW]) were derived and compared between MHD and the control. Logistic regression was used to determine the predictive value of these parameters for MACE. The receiver operating characteristic curve was utilized to compare the predictive differences of MACE between GWE and GLS. RESULTS: Compared with healthy individuals, MHD patients had significantly reduced GWE, GLS and elevated LVMI, GWW (all p < 0.001), while there was no significant difference in left ventricular ejection fraction. Twenty eight (30%) MHD patients experienced MACE. Two nested models adding GWE and GLS, respectively, showed that age (p < 0.005), GWE (p = 0.034), and GLS (p = 0.014) were independent predictors of MACE. The AUC derived from GWE for predicting MACE was significantly higher than that derived from GLS (0.836 vs. 0.743, p = 0.039). CONCLUSIONS: Myocardial work is a novel tool for assessing left ventricular myocardial performance in MHD patients. GWE is an independent predictor of MACE.

Exploring the underlying mechanisms of enteritis impact on golden pompano (Trachinotus ovatus) through multi-omics analysis.

Enteritis posed a significant health challenge to golden pompano (Trachinotus ovatus) populations. In this research, a comprehensive multi-omics strategy was implemented to elucidate the pathogenesis of enteritis by comparing both healthy and affected golden pompano. Histologically, enteritis was characterized by villi adhesion and increased clustering after inflammation. Analysis of the intestinal microbiota revealed a significant increase (P < 0.05) in the abundance of specific bacterial strains, including Photobacterium and Salinivibrio, in diseased fish compared to the healthy group. Metabolomic analysis identified 5479 altered metabolites, with significant impacts on terpenoid and polyketide metabolism, as well as lipid metabolism (P < 0.05). Additionally, the concentrations of several compounds such as calcitetrol, vitamin D2, arachidonic acid, and linoleic acid were significantly reduced in the intestines of diseased fish post-enteritis (P < 0.05), with the detection of harmful substances such as Efonidipine. In transcriptomic profiling, enteritis induced 68 upregulated and 73 downregulated genes, predominantly affecting steroid hormone receptor activity (P < 0.05). KEGG pathway enrichment analysis highlighted upregulation of SQLE and CYP51 in steroidogenesis, while the HSV-1 associated MHC1 gene exhibited significant downregulation. Integration of multi-omics results suggested a potential pathogenic mechanism: enteritis may have resulted from concurrent infection of harmful bacteria, specifically Photobacterium and Salinivibrio, along with HSV-1. Efonidipine production within the intestinal tract may have blocked certain calcium ion channels, leading to downregulation of MHC1 gene expression and reduced extracellular immune recognition. Upregulation of SQLE and CYP51 genes stimulated steroid hormone synthesis within cells, which, upon binding to G protein-coupled receptors, influenced calcium ion transport, inhibited immune activation reactions, and further reduced intracellular synthesis of anti-inflammatory substances like arachidonic acid. Ultimately, this cascade led to inflammation progression, weakened intestinal peristalsis, and villi adhesion. This study utilized multi-level omics detection to investigate the pathological symptoms of enteritis and proposed a plausible pathogenic mechanism, providing innovative insights into enteritis verification and treatment in offshore cage culture of golden pompano.

Potential mechanism of ginseng in the treatment of periodontitis based on network pharmacology and molecular docking.

OBJECTIVES: To explore the mechanism of ginseng in the treatment of periodontitis based on network pharmacology and molecular docking technology. METHODS: Potential targets of ginseng and periodontitis were obtained through various databases. The intersection targets of ginseng and periodontitis were obtained by using VENNY, the protein-protein interaction network relationship diagram was formed on the STRING platform, the core target diagram was formed by Cytoscape software, and the ginseng-active ingredient-target network diagram was constructed. The selected targets were screened for gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. The core targets of ginseng's active ingredients in treating periodontitis were analyzed by molecular docking technique. RESULTS: The 22 ginseng's active ingredients, 591 potential targets of ginseng's active ingredients, 2 249 periodontitis gene targets, and 145 ginseng-periodontitis intersection targets were analyzed. Ginseng had strong binding activity on core targets such as vascular endothelial growth factor A and epidermal growth factor receptor, as well as hypoxia induced-factor 1 (HIF-1) signaling pathway and phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) signaling pathway. CONCLUSIONS: Ginseng and its active components can regulate several signaling pathways such as HIF-1 and PI3K-Akt, thereby indicating that ginseng may play a role in treating periodontitis through multiple pathways.

The application of ferrous and graphitic N modified graphene-based composite cathode material in the bio-electro-Fenton system driven by sediment microbial fuel cells to degrade methyl orange.

In this work, the ferrous (Fe2+) and graphitic N modified graphene-based composite cathode materials (N-rGO/Fe3O4) were developed through an in-situ reduction method, aiming to facilitate the two-electron pathway in the oxidation-reduction process. This approach generated a specific concentration of H2O2, enabling the construction of a sediment bio-electro-Fenton system using Fe2+ released from the cathode materials. Notably, this system operates without the need for proton exchange membranes. During the cathode material preparation, the utilization of Fe2+ as a reduction agent for graphene oxide (GO), triggered ammonia water to form graphitic N in graphene sheets. This addition enhanced the two-electron pathway, resulting in increased H2O2 production. Specifically, when the Fe2+ concentration was maintained at 0.1 mol/L, precise preparation of N-rGO/Fe3O4 occurred, leading to a maximum output voltage of 0.528 V and a maximum power density of 178.17 mW/m2. The degradation of methyl orange (MO) reached 68.91% within a 25-h period, a phenomenon contributed to the presence of graphitic N in the graphene sheets. H2O2, a byproduct of the two-electron pathway in cathode oxidation reduction reaction, played a crucial role in constructing the bio-electro-Fenton system. This system, in conjunction with Fe2+ released from N-rGO/Fe3O4, facilitated the complete degradation process of MO.

Iron-Confined CRISPR/Cas9-Ribonucleoprotein Delivery System for Redox-Responsive Gene Editing.

Clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein 9 (Cas9) is a promising gene editing tool to treat diseases at the genetic level. Nonetheless, the challenge of the safe and efficient delivery of CRISPR/Cas9 to host cells constrains its clinical applicability. In the current study, a facile, redox-responsive CRISPR/Cas9-Ribonucleoprotein (RNP) delivery system by combining iron-coordinated aggregation with liposomes (Fe-RNP@L) is reported. The Fe-RNP is formed by the coordination of Fe3+ with amino and carboxyl groups of Cas9, which modifies the lipophilicity and surface charge of RNP and alters cellular uptake from primary endocytosis to endocytosis and cholesterol-dependent membrane fusion. RNP can be rapidly and reversibly released from Fe-RNP in response to glutathione without loss of structural integrity and enzymatic activity. In addition, iron coordination also improves the stability of RNP and substantially mitigates cytotoxicity. This construct enabled highly efficient cytoplasmic/nuclear delivery (≈90%) and gene-editing efficiency (≈70%) even at low concentrations. The high payload content, high editing efficiency, good stability, low immunogenicity, and ease of production and storage, highlight its potential for diverse genome editing and clinical applications.

LncRNA FOXD1-AS1 regulates pancreatic cancer stem cell properties and 5-FU resistance by regulating the miR-570-3p/SPP1 axis as a ceRNA.

Cancer stem cells (CSCs) play a pivotal role in the pathogenesis of human cancers. Previous studies have highlighted the role of long non-coding RNA (lncRNA) in modulating the stemness of CSCs. In our investigation, we identified an upregulation of lncRNA FOXD1-AS1 in CSCs. The enforced expression of lncRNA FOXD1-AS1 promotes tumorigenesis and self-renewal in pancreatic cancer CSCs. Conversely, the knockdown of lncRNA FOXD1-AS1 inhibits tumorigenesis and self-renewal in pancreatic cancer CSCs. Furthermore, our findings reveal that lncRNA FOXD1-AS1 enhances self-renewal and tumorigenesis in pancreatic cancer CSCs by up-regulating osteopontin/secreted phosphoprotein 1(SPP1) and acting as a ceRNA to sponge miR-570-3p in pancreatic cancer (PC) CSCs. Additionally, lncRNA FOXD1-AS1 depleted pancreatic cancer cells exhibit heightened sensitivity to 5-FU-indued cell growth inhibition and apoptosis. Analysis of patient-derived xenografts (PDX) indicates that a low level of lncRNA FOXD1-AS1 may serve as a predictor of 5-FU benefits in PC patients. Moreover, the introduction of SPP1 can reverse the sensitivity of lncRNA FOXD1-AS1-knockdown PC cells to 5-FU-induced cell apoptosis. Importantly, molecular studies have indicated that the elevated levels of lncRNAFOXD1-AS1 in PC are facilitated through METTL3 and YTHDF1-dependent m6A methylation. In summary, our results underscore the critical functions of lncRNA FOXD1-AS1 in the self-renewal and tumorigenesis of pancreatic cancer CSCs, positioning lncRNA FOXD1-AS1 as a promising therapeutic target for PC.

Gastrointestinal perforation associated with bevacizumab in metastatic colorectal cancer.

OBJECTIVE: To investigate the risk factors for gastrointestinal perforation in metastatic colorectal cancer patients receiving bevacizumab. METHODS: We retrospectively reviewed 217 patients with metastatic colorectal cancer receiving bevacizumab to investigate the risk factors for gastrointestinal perforation. Three patients occurred intestinal perforation after receiving bevacizumab. We analyzed the clinical characteristics of three patients with intestinal perforation. RESULTS: All patients receiving bevacizumab. Three of 217 patients occurred intestinal perforation after receiving bevacizumab. Patient no. 1 was 70 years old, female, having history of intestinal obstruction. The patient occurred intestinal perforation and ultimately died after receiving bevacizumab. Patient no. 2 was 59 years old, female, having history of intestinal obstruction. The patient occurred intestinal perforation after receiving bevacizumab, and recovered smoothly after symptomatic treatment. Patient no. 3 was 60 years old, female, having history of intestinal obstruction. The patient occurred intestinal perforation and ultimately died after receiving bevacizumab. CONCLUSIONS: Patients with advanced colorectal cancer receiving bevacizumab are at risk of gastrointestinal perforation. The patient's age, gender and history of bowel obstruction may be associated with gastrointestinal perforation.

Histidine modulates amyloid-like assembly of peptide nanomaterials and confers enzyme-like activity.

Amyloid-like assembly is not only associated with pathological events, but also leads to the development of novel nanomaterials with unique properties. Herein, using Fmoc diphenylalanine peptide (Fmoc-F-F) as a minimalistic model, we found that histidine can modulate the assembly behavior of Fmoc-F-F and induce enzyme-like catalysis. Specifically, the presence of histidine rearranges the ß structure of Fmoc-F-F to assemble nanofilaments, resulting in the formation of active site to mimic peroxidase-like activity that catalyzes ROS generation. A similar catalytic property is also observed in Aß assembled filaments, which is correlated with the spatial proximity between intermolecular histidine and F-F. Notably, the assembled Aß filaments are able to induce cellular ROS elevation and damage neuron cells, providing an insight into the pathological relationship between Aß aggregation and Alzheimer's disease. These findings highlight the potential of histidine as a modulator in amyloid-like assembly of peptide nanomaterials exerting enzyme-like catalysis.

Effect of Different Liver Resection Modalities on the Prognosis of Patients with Hepatocellular Carcinoma on the Left Lateral Lobe.

Purpose: To investigate the effect of different liver resection modalities on the prognosis of left lateral lobe hepatocellular carcinoma (HCC) patients. Methods: 315 patients with HCC on left lateral lobe were divided into open left lateral lobectomy (LLL) group (n=249) and open left hepatectomy (LH) group (n=66). The differences in long-term prognosis between two groups were compared. Results: The results showed that narrow resection margin (Hazard Ratio (HR):1.457, 95% Confidential Interval (CI): 1.038-2.047; HR:1.415, 95% CI: 1.061-1.887), tumor diameter > 5 cm (1.645, 1.161-2.330; 1.488, 1.123-1.971), multiple tumors (2.021, 1.330-3.073; 1.987, 1.380-2.861), and microvascular invasion (MVI) (1.753, 1.253-2.452; 1.438, 1.087-1.902) are independent risk factors for overall survival (OS) and tumor recurrence (TR), while liver resection modality is not. After propensity score matching, liver resection modality is not an independent risk factor for OS and TR. Further analysis revealed that wide resection margins were achieved in all patients in the LH group but only 59.0% patients in the LLL group. The OS and TR rates were not significantly different between wide patients with resection margins in LLL group and LH group (P=0.766 and 0.919, respectively), but significantly different between patients with narrow resection margins in LLL group and LH group (P=0.012 and 0.017, respectively). Conclusion: Liver resection modality is not an independent risk factor for the prognosis of patients with HCC on the left lateral lobe as long as wide margins are obtained. Nevertheless, with narrow margins, patients who underwent LH rather than LLL did better.

Rapid and Sensitive Detection of Streptococcus iniae in Trachinotus ovatus Based on Multienzyme Isothermal Rapid Amplification.

Infectious diseases caused by Streptococcus iniae lead to massive death of fish, compose a serious threat to the global aquaculture industry, and constitute a risk to humans who deal with raw fish. In order to realize the early diagnosis of S. iniae, and control the outbreak and spread of disease, it is of great significance to establish fast, sensitive, and convenient detection methods for S. iniae. In the present study, two methods of real-time MIRA (multienzyme isothermal rapid amplification, MIRA) and MIRA-LFD (combining MIRA with lateral flow dipsticks (LFD)) for the simA gene of S. iniae were established, which could complete amplification at a constant temperature of 42 °C within 20 min. Real-time MIRA and MIRA-LFD assays showed high sensitivity (97 fg/µL or 7.6 × 102 CFU/mL), which were consistent with the sensitivity of real-time PCR and 10 times higher than that of PCR with strong specificity, repeatability simplicity, and rapidity for S. iniae originating from Trachinotus ovatus. In summary, real-time MIRA and MIRA-LFD provide effective ways for early diagnosis of S. iniae in aquaculture, especially for units in poor conditions.

Ginsenoside Rb3 inhibits osteoclastogenesis via ERK/NF-κB signaling pathway in vitro and in vivo.

OBJECTIVE: The objective of the study was to determine the anti-osteoclastogenic potential of ginsenoside Rb3 for the treatment of periodontitis. METHODS: The anti-osteoclastogenic effect was determined using RANKL-induced RAW264.7 cells and murine bone marrow-derived macrophages followed by TRAP and phalloidin staining. Expression of osteoclastogenesis-related genes and proteins were examined by qPCR and WB. Activation of signaling pathways was detected by WB and IHC techniques. Experimental periodontitis rat model was built up by gingival injections of P. gingivalis LPS. After 21 days of Rb3 treatment, rats were sacrificed for micro-CT, IHC, H&E, and TRAP staining analyses. RESULTS: Rb3 dramatically inhibits RANKL-induced osteoclastogenesis. Nfatc1, Mmp9, Ctsk, Acp5 mRNA, and MMP9, CTSK proteins were dose-dependently downregulated by Rb3 pretreatment. WB results revealed that Rb3 suppressed activations of p38 MAPK, ERK, and p65 NF-κB, and the inhibition of ERK was most pronounced. Consistently, IHC analysis revealed that p-ERK was highly expressed in alveolar bone surface, blood vessels, odontoblasts, and gingival epithelia, which were notably suppressed by Rb3 treatment. H&E staining and micro-CT analyses showed that Rb3 significantly attenuated gingivitis and alveolar bone resorption in rats. CONCLUSION: Rb3 inhibits RANKL-induced osteoclastogenesis and attenuates P. gingivalis LPS-induced gingivitis and alveolar bone resorption in rats via ERK/NF-κB signaling pathway.

New Insights into the Traditional Charge Compensation Theory: Amphoteric Behavior of TiO2 under the Guidance of Supply-Demand Relationship.

Polymerization degree theory and traditional charge compensation theory are the most fundamental principles to understand the structure and properties of oxide melts. It can well explain the behavior characteristics of acidic oxides and basic oxides in a melt. However, the amphoteric behavior of oxides cannot be explained well by these two theories. Herein, the octahedral connection mode and the behavior of the amphoteric transition of TiO2 are analyzed by molecular dynamics simulation, and then, a calculation model which can quantitatively calculate the amphoteric transition of the oxide is established by analyzing a large number of data. On the basis of the model, a novel theory of supply and demand is put forward, which can explain the amphoteric transition behavior of oxides very well. To a great extent, the supply and demand theory makes up for the deficiency of the atomic structure theory of oxide melts and provides mechanism explanation and model prediction for the oxide amphoteric transformation behavior.

Prognostic Nomograms Combined Adjuvant Lenvatinib for Hepatitis B Virus-related Hepatocellular Carcinoma With Microvascular Invasion After Radical Resection.

Background and Aim: Microvascular invasion (MVI) has been established as one of the most important contributors to the prognosis of primary hepatocellular carcinoma (HCC). The objective of this study was to investigate the potential effect of postoperative adjuvant therapy with lenvatinib on the long-term prognosis after radical resection in hepatitis B virus (HBV)-related HCC patients with MVI, as well as to predict the long-term survival based on nomograms. Methods: Data from 293 HBV-related hepatocellular carcinoma patients with histologically confirmed MVI who underwent R0 resection at Eastern Hepatobiliary Surgery Hospital (EHBH) was retrospectively analyzed. 57 patients received postoperative adjuvant therapy with lenvatinib, while 236 patients did not. The survival outcome of patients who received postoperative adjuvant lenvatinib versus those who did not was analyzed. Results: The 1-year, 2-year recurrence rates and survival rates of the lenvatinib group were improved compared to the non-lenvatinib group (15.9%, 43.2% vs 40.1%, 57.2%, P=0.002; 85.8%, 71.2% vs 69.6%, 53.3%, P=0.009, respectively). Similar findings were also observed after Propensity Score Matching (PSM) compared to non-PSM analyses The 1-year, 2-year recurrence rates and survival rates were more favorable for the lenvatinib group compared to the non-lenvatinib group (15.9%, 43.2% vs 42.1%, 57.4%, P=0.028; 85.8%, 71.2% vs 70.0%, 53.4%, P=0.024, respectively). As shown by univariate and multivariate analyses, absence of adjuvant lenvatinib treatment was identified as an independent risk factor for recurrence and survival. The established nomograms displayed good performance for the prediction of recurrence and survival, with a C-index of 0.658 and 0.682 respectively. Conclusions: Postoperative adjuvant therapy with lenvatinib was associated with improved long-term prognosis after R0 Resection in HBV-related HCC patients with MVI, which could be accurately predicted from nomograms.

BAP31 Promotes Proliferation, Invasion, and Metastasis of Liver Cancer Cells via Activating PI3K/AKT Pathway.

Background: Many breakthroughs have been made in the clinical treatment of liver cancer, but there are still many liver cancer patients with limited treatment methods. Therefore, it is very important to find targets for early diagnosis and specific treatment of liver cancer. Methods: During the operation, 32 pairs of tumor tissues and corresponding normal liver tissues were acquired from patients. The mRNA expression was measured by qPCR. The protein expression was evaluated via Western blot. Flow cytometry assay was performed to measure the cells apoptosis. CCK-8 assay was performed to detect cell proliferation. Transwell chamber assay was applied to detect migration and invasion of SNU-449 cells. Results: BAP31 was upregulated in liver cancer tissues and cells. Knockdown of BAP31 repressed cell proliferation and enhanced cell apoptosis of liver cancer. Knockdown of BAP31 apparently upregulated apoptosis-related proteins (Bax and Caspase-3), while it downregulated antiapoptotic proteins (Bcl-2). Knockdown of BAP31 repressed migration and invasion of SNU-449 cells. In contrast with the control and si-NC group, protein expression of MMP-2 and MMP-9 was obviously lower after si-BAP31 transfection of cells. Knockdown of BAP31 repressed PI3K/AKT signaling pathways in liver cancer cells. Conclusion: Knockdown of BAP31 repressed cell proliferation, migration, and invasion in liver cancer by suppressing PI3K/AKT/mTOR signaling pathways.

Left atrial reservoir strain is an outstanding predictor of adverse cardiovascular outcomes in patients undergoing maintenance hemodialysis: Assessment via three-dimensional speckle tracking echocardiography.

BACKGROUND: There is a paucity of literature focusing left atrium (LA) in patients undergoing maintenance hemodialysis (MHD). HYPOTHESIS: We used three-dimensional speckle tracking echocardiography (3DSTE) to evaluate LA in MHD patients and to explore its predictive value for adverse outcomes. METHODS: Echocardiography was performed on 130 consecutively enrolled MHD patients without previous cardiac diseases. Conventional and 3DSTE parameters of LA were obtained. The MHD cohort was then followed and the end point was major adverse cardiovascular events (MACEs). LA strain indices, including reservoir strain (LASr), conduit strain (LAScd), and contractile strain (LASct), were measured and compared between patients with and without MACEs. RESULTS: Patients were prospectively followed up for a median of 40.5 (interquartile range: 26.3-48.0) months. During follow-up, 43 patients met the end point. These patients had larger LA size and reduced LA strains (LA maximal volume indexed: 45.1 ± 11.9 vs. 33.8 ± 6.9ml/m2 ; LASr: 20.2 ± 3.5 vs. 27.2 ± 3.3%; LAScd: -12.3 ± 5.2 vs. -14.5±4.0%; LASct: -8.0 ± 4.2 vs. -13.2 ± 3.7%; all p<.05), compared with those without MACEs. Multivariable regression analysis showed LASr was the strongest predictor of MACEs (hazard ratio, 0.69; 95% confidence interval, 0.54-0.89; p=.004). Univarite Kaplan-Meier analysis revealed the incidence of MACEs in the impaired LASr (<24.2%) group was significantly higher than in the normal LASr group (log rank p<.001). CONCLUSIONS: LASr derived from 3DSTE is an independent predictor of MACEs and cardiac death in MHD patients, superior to LV parameters and LA volume indices.

A duplicated amh is the master sex-determining gene for Sebastes rockfish in the Northwest Pacific.

Teleost fish are the most diverse group of vertebrates and provide opportunities to study the evolution of sex determination (SD) systems. Using genomic and functional analyses, we identified a male-specific duplication of anti-Müllerian hormone (amh) gene as the male master sex-determining (MSD) gene in Sebastes schlegelii. By resequencing 10 males and 10 females, we characterized a 5 kb-long fragment in HiC_Scaffold_12 as a male-specific region, which contained an amh gene (named amhy). We then demonstrated that amhy is a duplication of autosomal amh that was later translocated to the ancestral Y chromosome. amha and amhy shared high-nucleotide identity with the most significant difference being two insertions in intron 4 of amhy. Furthermore, amhy overexpression triggered female-to-male sex reversal in S. schlegelii, displaying its fundamental role in driving testis differentiation. We developed a PCR assay which successfully identified sexes in two species of northwest Pacific rockfish related to S. schlegelii. However, the PCR assay failed to distinguish the sexes in a separate clade of northeast Pacific rockfish. Our study provides new examples of amh as the MSD in fish and sheds light on the convergent evolution of amh duplication as the driving force of sex determination in different fish taxa.

Molecular characterization and functional analysis of cyp11a and cyp11b in black rockfish (Sebastes schlegelii).

The cyp11 includes cyp11a and cyp11b in most mammals and teleosts, encoded cholesterol side chain lyase and 11ß-hydroxylase, respectively. It is essential in steroid hormone synthesis. However, studies on the regulation of cyp11 are limited, especially in teleosts. In this study, the molecular characterization and function of cyp11a and cyp11b of black rockfish was investigated. Both of them showed high homology with other teleost counterparts by phylogenetic analysis. The expression of cyp11a and cyp11b exhibited a clear sexually dimorphic pattern, with a higher expression level in testis than that of in ovaries. During the different developmental stages (40 dpf, 80 dpf, 190 dpf, 360 dpf, 720 dpf), the expression of cyp11a was earlier than cyp11b. In situ hybridization results showed that cyp11a and cyp11b were mainly expressed in oogonia and oocytes of the ovary. They were located in spermatogonia and interstitial compartment in the 1.5-year-old gonads, and spermatocytesgonia and the peritubular myoid cell of the testis in the 2.5-year-old gonads. To explore the distinct roles of cyp11a and cyp11b in gonads, oestrogen and androgens were used to stimulate the primary testicular and ovarian cells. The expressions of cyp11a and cyp11b were tested under different dose of 17α-methyltestosterone (17α-MT) and 17ß-estradiol (E2). The results showed cyp11a was significantly increased at 10-6  mol ml-1 of 17α-MT and 10-8  mol ml-1 of E2 in ovary and 10-10  mol ml-1 of 17α-MT and E2 in testis, while cyp11b was significantly decreased after 17α-MT and E2 treatment. These results indicated that cyp11a and cyp11b were likely to have different functions, and also implied they might play an important roles in the differentiation of gonads and the synthesis of steroids in black rockfish.