SASH1 contributes to glial cell migration in the early development of the central nervous system.

SAM and SH3 domain-containing 1 (SASH1), a member of the SLy protein family, is a tumor suppressor gene that has been studied for its association with various cancers. SASH1 is highly expressed in the mammalian central nervous system, particularly in glial cells, and is expressed in the central nervous system during zebrafish embryo development. However, SASH1's role in brain development has rarely been investigated. In this study, Morpholino oligonucleotides (MO) were used to down-regulate sash1a expression in zebrafish to observe morphological changes in the brain. Three transgenic zebrafish lines, Tg(gfap:eGFP), Tg(hb9:eGFP), and Tg(coro1a:eGFP) were selected to observe changes in glial cells, neurons, and immune cells after sash1a knockdown. Our results showed that the number of microglia residing in the developmental brain was reduced, whereas the axonal growth of caudal primary motor neurons was unaffected by sash1a downregulation. And more significantly, the gfap + glia presented abnormal arrangements and disordered orientations in sash1a morphants. The similar phenotype was verified in the mutation induced by the injection of cas9 mRNA and sash1a sgRNA. We further performed behavioral experiments in zebrafish larvae that had been injected with sash1a MO at one-cell stage, and found them exhibiting abnormal behavior trajectories. Moreover, injecting the human SASH1 mRNA rescued these phenomena in sash1a MO zebrafish. In summary, our study revealed that the downregulation of SASH1 leads to malformations in the embryonic brain and disorganization of glial cell marshalling, suggesting that SASH1 plays an important role in the migration of glial cells during embryonic brain development.

Cooperation of long noncoding RNA LOC100909675 and transcriptional regulator CTCF modulates Cdk1 transcript to control astrocyte proliferation.

Astrocyte activation and proliferation contribute to glial scar formation during spinal cord injury (SCI), which limits nerve regeneration. The long noncoding RNAs (lncRNAs) are involved in astrocyte proliferation and act as novel epigenetic regulators. Here, we found that lncRNA-LOC100909675 (LOC9675) expression promptly increased after SCI and that reducing its expression decreased the proliferation and migration of the cultured spinal astrocytes. Depletion of LOC9675 reduced astrocyte proliferation and facilitated axonal regrowth after SCI. LOC9675 mainly localized in astrocytic nuclei. We used RNA-seq to analyze gene expression profile alterations in LOC9675-depleted astrocytes and identified the cyclin-dependent kinase 1 (Cdk1) gene as a hub candidate. Our RNA pull-down and RNA immunoprecipitation assays showed that LOC9675 directly interacted with the transcriptional regulator CCCTC-binding factor (CTCF). Dual-luciferase reporter and chromatin immunoprecipitation assays, together with downregulated/upregulated expression investigation, revealed that CTCF is a novel regulator of the Cdk1 gene. Interestingly, we found that with the simultaneous overexpression of CTCF and LOC9675 in astrocytes, the Cdk1 transcript was restored to the normal level. We then designed the deletion construct of LOC9675 by removing its interacting region with CTCF and found this effect disappeared. A transcription inhibition assay using actinomycin D revealed that LOC9675 could stabilize Cdk1 mRNA, while LOC9675 depletion or binding with CTCF reduced Cdk1 mRNA stability. These data suggest that the cooperation between CTCF and LOC9675 regulates Cdk1 transcription at a steady level, thereby strictly controlling astrocyte proliferation. This study provides a novel perspective on the regulation of the Cdk1 gene transcript by lncRNA LOC9675.

Histone acetyltransferase KAT2A modulates neural stem cell differentiation and proliferation by inducing degradation of the transcription factor PAX6.

Neural stem cells (NSCs) proliferation and differentiation rely on proper expression and posttranslational modification of transcription factors involved in the determination of cell fate. Further characterization is needed to connect modifying enzymes with their transcription factor substrates in the regulation of these processes. Here, we demonstrated that the inhibition of KAT2A, a histone acetyltransferase, leads to a phenotype of small eyes in the developing embryo of zebrafish, which is associated with enhanced proliferation and apoptosis of NSCs in zebrafish eyes. We confirmed that this phenotype is mediated by the elevated level of PAX6 protein. We further verified that KAT2A negatively regulates PAX6 at the protein level in cultured neural stem cells of rat cerebral cortex. We revealed that PAX6 is a novel acetylation substrate of KAT2A and the acetylation of PAX6 promotes its ubiquitination mediated by the E3 ligase RNF8 that facilitated PAX6 degradation. Our study proposes that KAT2A inhibition results in accelerated proliferation, delayed differentiation, or apoptosis, depending on the context of PAX6 dosage. Thus, the KAT2A/PAX6 axis plays an essential role to keep a balance between the self-renewal and differentiation of NSCs.

MEF2C contributes to axonal branching by regulating Kif2c transcription.

Neurons are post-mitotic cells, with microtubules playing crucial roles in axonal transport and growth. Kinesin family member 2c (KIF2C), a member of the Kinesin-13 family, possesses the ability to depolymerize microtubules and is involved in remodelling the microtubule lattice. Myocyte enhancer factor 2c (MEF2C) was initially identified as a regulator of muscle differentiation but has recently been associated with neurological abnormalities such as severe cognitive impairment, stereotyping, epilepsy and brain malformations when mutated or deleted. However, further investigation is required to determine which target genes MEF2C acts upon to influence neuronal function as a transcription regulator. Our data demonstrate that knockdown of both Mef2c and Kif2c significantly impacts spinal motor neuron development and behaviour in zebrafish. Luciferase reporter assays and chromosome immunoprecipitation assays, along with down/upregulated expression analysis, revealed that MFE2C functions as a novel transcription regulator for the Kif2c gene. Additionally, the knockdown of either Mef2c or Kif2c expression in E18 cortical neurons substantially reduces the number of primary neurites and axonal branches during neuronal development in vitro without affecting neurite length. Finally, depletion of Kif2c eliminated the effects of overexpression of Mef2c on the neurite branching. Based on these findings, we provided novel evidence demonstrating that MEF2C regulates the transcription of the Kif2c gene thereby influencing the axonal branching.

Diet with optimal glutathione supplement improves growth, nonspecific immunity, intestinal microbiota, and antioxidant ability in Micropterus salmoides.

In this study, Micropterus salmoides were fed with dietary glutathione (GSH, 0, 100, 300, and 500 mg/kg) for 56 days to investigate its effects on growth performance, serum nonspecific immunity, liver antioxidant capacity, tissue morphology, and intestinal microbiota. The results showed that the survival rate, weight gain rate, and specific growth rate and condition factor increased, whereas the feed conversion ratio, hepato-somatic index, and viscerosomatic index decreased in the GSH groups. Compared with the control group, the serum total protein content significantly increased, whereas the triglyceride and total cholesterol significantly decreased in the 300-mg/kg dietary GSH group. The activities of lysozyme, alkaline phosphatase, and acid phosphatase were significantly higher in GSH-supplemented groups, peaking at 300-mg/kg GSH. GSH supplementation significantly increased total antioxidant capacity and decreased malondialdehyde content, with the most pronounced effects at 300-mg/kg GSH. Further antioxidant indicators showed that a dietary supplement of 300-mg/kg GSH significantly increased the activities of superoxide dismutase, glutathione transferase, endogenous glutathione, glutathione reductase, and catalase. At 300-mg/kg GSH, the liver exhibited improved characteristics with alleviated vacuolation and hepatocyte nuclear shift, and intestine showed enhanced structure with increased villus height and intestinal wall thickness. Additionally, a 300-mg/kg GSH supplementation improved the diversity of intestinal microbiota, increased the abundance of probiotics such as Bacillus, and inhibited the development of pathogenic bacteria such as Plesiomonas. Overall, the results suggest that the effect of GSH addition on improving growth performance, nonspecific immunity, antioxidant capacity, and intestinal microbiota of M. salmoides is best in the 300-mg/kg addition group. Based on second-degree polynomial regression analysis of weight gain, the optimum requirement of dietary GSH in M. salmoides is a 336.84-mg/kg diet.

Deficiency of Kif15 gene inhibits tumor growth due to host CD8+T lymphocytes increase.

Kif15, also name kinesin-12, is a microtubule (MT) associate protein, which functions as a regulator of MT-dependent transport or spindle organization. Previous studies reported Kif15 increases in many tumors, however the effect of host Kif15 gene lack on tumor growth is not investigated. In this study, CRISPR/Cas9 mediated Kif15 gene knockout (Kif15-/-) mice were established and HE (Hematoxylin-Eosin) assay revealed no significant differences of morphology in most adult tissues (heart, liver, lung, kidney, and brain) except a retarded development of spleen in adult Kif15-/- mice. RNA sequence analysis of adult spleen tissues of Kif15-/- and Kif15+/+ mice was performed, and the results revealed that a total of 438 mRNAs were significantly differentially expressed in Kif15 knockout spleen, showing the top biological process was immune system process. FCM (Flow Cytometry) assay showed the percentage of CD8+ T lymphocytes notably increased in spleens of 9 w and 12 w old Kif15-/- mice. The CD8+ T lymphocytes are cytotoxic effector cells fighting against tumor. We thus detected the tumor growth in Kif15-/- mice using the melanoma cells inoculated subcutaneously. The tumor size significantly reduced in Kif15-/- mice. We finally detected whether Kif15 dysfunction affects the phagocytic function of macrophages on tumor cells, and the result showed Kif15 inhibitor treated macrophages significantly promoted the phagocytosis in vitro. In summary, this study revealed that the tumor-bearing mice of Kif15 gene deficiency notably inhibited tumor growth due to innate immune activation, which was the first report of the relation of Kif15 on the immunoreactivity.

Maternal RNA binding protein with multiple splicing 2 (RBPMS2) is involved in mouse blastocyst formation through the bone morphogenetic protein pathway.

RESEARCH QUESTION: Is early embryo development in mice influenced by RNA binding protein with multiple splicing 2 (RBPMS2), a maternal factor that accumulates and is stored in the cytoplasm of mature oocytes? DESIGN: The expression patterns of RBPMS2 in mouse were analysed using quantitative real-time PCR (qRT PCR) and immunofluorescence staining. The effect of knockdown of RBPMS2 on embryo development was evaluated through a microinjection of specific morpholino or small interfering RNA. RNA sequencing was performed for mechanistic analysis. The interaction between RBPMS2 and the bone morphogenetic protein (BMP) pathway was studied using BMP inhibitor and activator. The effect on the localization of E-cadherin was determined by immunofluorescence staining. RESULTS: Maternal protein RBPMS2 is highly expressed in mouse oocytes, and knockdown of RBPMS2 inhibits embryo development from the morula to the blastocyst stage. Mechanistically, RNA sequencing showed that the differentially expressed genes were enriched in the transforming growth factor-ß (TGF-ß) signalling pathway. BMPs are members of the TGF-ß superfamily of growth factors. It was found that the addition of BMP inhibitor to the culture medium led to a morula-stage arrest, similar to that seen in RBPMS2 knockdown embryos. This morula-stage arrest defect caused by RBPMS2 knockdown was partially rescued by BMP activator. Furthermore, the localization of E-cadherin to the membrane was impaired in response to a knockdown of RBPMS2 or inhibition of the BMP pathway. CONCLUSION: This study suggests that RBPMS2 activates the BMP pathway and thus influences the localization of E-cadherin, which is important for early mouse embryo development during blastocyst formation.

Construction and efficacy of Aeromonas veronii mutant Δhcp as a live attenuated vaccine for the largemouth bass (Micropterus salmoides).

Aeromonas veronii is a human and animal co-pathogenic bacterium that could have a significant negative impact on both human health and aquaculture. In this study, a mutant strain of A. veronii with deletion of the hemolysin co-regulated protein (hcp) gene was constructed (Δhcp-AV). Compared with the wild strain, Δhcp-AV showed significantly reduced growth capacity and biofilm formation ability. Motility tests showed that the hcp gene had no significant effect on the swimming and swarming ability. In addition, the pathogenicity was also reduced. To evaluate the efficacy of Δhcp-AV as a live attenuated vaccine for prevention of Aeromonas veronii infection, we compared the immune response of largemouth bass (Micropterus salmoides) after immunization with 500 µL of 1.47 × 105 CFU/mL of Δhcp-AV and 4 × 108 CFU/mL of inactivated A. veronii. Obvious increases of serum immune related enzyme activity were observed in immunization groups. Expression levels of immune-related genes in Δhcp-AV group were up-regulated, and higher than those in inactivated A. veronii group. After challenging with live A. veronii, the relative percent survival (RPS) was 100% in Δhcp- AV group, whereas the RPS was 76.67% in inactivated A. veronii group. Our data suggest that the live attenuated vaccine Δhcp- AV could elicit a stronger immune response and provide a higher RPS than inactivated A. veronii. These data suggest that hcp gene is an important virulence factor of A. veronii, and the live attenuated vaccine Δhcp-AV is safe and effective for prevention A. veronii infection in M. salmoides farming.

Kif15 deficiency contributes to depression-like behavior in mice.

Neuropsychiatric disorders have a high incidence worldwide. Kinesins, a family of microtubule-based molecular motor proteins, play essential roles in intracellular and axonal transport. Variants of kinesins have been found to be related to many diseases, including neurodevelopmental/neurodegenerative disorders. Kinesin-12 (also known as Kif15) was previously found to affect the frequency of both directional microtubule transports. However, whether Kif15 deficiency impacts mood in mice is yet to be investigated. In this study, we used the CRISPR/Cas9 method to obtain Kif15-/- mice. In behavioral tests, Kif15-/- female mice exhibited prominent depressive characteristics. Further studies showed that the expression of BDNF was significantly decreased in the frontal cortex, corpus callosum, and hippocampus of Kif15-/- mice, along with the upregulation of Interleukin-6 and Interleukin-1ß in the corpus callosum. In addition, the expression patterns of AnkG were notably changed in the developing brain of Kif15-/- mice. Based on our previous studies, we suggested that this appearance of altered AnkG was due to the maladjustment of the microtubule patterns induced by Kif15 deficiency. The distribution of PSD95 in neurites notably decreased after cultured neurons treated with the Kif15 inhibitor, but total PSD95 protein level was not impacted, which revealed that Kif15 may contribute to PSD95 transportation. This study suggested that Kif15 may serve as a potential target for future depression studies.

Resection of sigmoid cancer with bladder invasion using laparoscopic combined with a cystoscopic holmium laser: an innovative surgical procedure.

The aim of this study was to introduce a new surgical procedure for the resection of sigmoid colon tumours invading the bladder by combining laparoscopy and cystoscopy, and the feasibility and safety of the method were verified. The data of 6 patients with sigmoid colon cancer invading the bladder in a tertiary hospital in Chongqing from January 2020 to October 2022 were collected, sigmoid colon tumour resection was performed by this procedure, and the data related to the surgery were recorded. All six patients successfully underwent sigmoid colon tumour resection, and all sigmoid colon and bladder resections had negative margins. The mean total operative time was 211.66 ± 27.33 min, and the mean resection time of the bladder tumour was 22.16 ± 4.63 min. The median blood loss was 100 ml, and the mean number of retrieved lymph nodes was nineteen. There were no serious intraoperative complications in any of the cases. After operation, the first flatus and defecation were 4 and 4.5 days, respectively. The mean time of drainage tube retention and the time of bladder flushing were 3 and 1.5 days, respectively. The mean time of urinary tube retention was 7.5 days. There were no intestinal obstructions, dysuria, or other complications. For patients with sigmoid colon tumours invading the bladder, this method can effectively resect sigmoid colon tumours and minimize the loss of bladder tissue at the same time, which helps to prolong the survival of these patients. The surgical method is safe, reliable, and feasible.

Plastid diversity and chromoplast biogenesis in differently coloured carrots: role of the DcOR3Leu gene.

MAIN CONCLUSION: Distinct plastid types and ultrastructural changes are associated with differences in carotenoid pigment profiles in differently coloured carrots, and a variant of the OR gene, DcOR3Leu is vital for chromoplast biogenesis. Accumulation of different types and amounts of carotenoids in carrots impart different colours to their taproots. In this study, the carotenoid pigment profiles, morphology, and ultrastructure of plastids in 25 carrot varieties with orange, red, yellow, or white taproots were investigated by ultra-high performance liquid chromatography as well as light and transmission electron microscopy. α-/ß-Carotene and lycopene were identified as colour-determining carotenoids in orange and red carrots, respectively. In contrast, lutein was identified as the colour-determining carotenoid in almost all tested yellow and white carrots. The latter contained only trace amounts of lutein as a unique detectable carotenoid. Striking differences in plastid types that coincided with distinct carotenoid profiles were observed among the differently coloured carrots. Microscopic analysis of the different carotenoid pigment-loaded plastids revealed abundant crystalloid chromoplasts in the orange and red carrots, whereas amyloplasts were dominant in most of the yellow and white carrots, except for the yellow carrot 'Yellow Stone', where yellow chromoplasts were observed. Plastoglobuli and crystal remnants, the carotenoid sequestering substructures, were identified in crystalloid chromoplasts. Crystal remnants were often associated with a characteristic undulated internal membrane in orange carrots or several undulated membranes in red carrots. No crystal remnants, but some plastoglobuli, were observed in the plastids of all tested yellow and white carrots. In addition, the presence of chromoplast in carrot taproots was found to be associated with DcOR3Leu, a natural variant of DcOR3, which was previously reported to be co-segregated with carotene content in carrots. Knocking out DcOR3Leu in the orange carrot 'Kurodagosun' depressed chromoplast biogenesis and led to the generation of yellow carrots. Our results support that DcOR3Leu is vital but insufficient for chromoplasts biogenesis in carrots, and add to the understanding of the formation of chromoplasts in carrots.

L-leucine promotes axonal outgrowth and regeneration via mTOR activation.

Discovering safe and effective drugs that promote neuron regeneration is an essential strategy for the recovery of central nervous system injuries. In this study, we found that L-leucine, an essential amino acid obtained from both supplements and food sources, could dramatically boost axonal outgrowth and regeneration. First, the effects of L-leucine on neurons were evaluated by cell apoptosis, survival, and death assays, and the results showed no changes in these processes after treatment. By live cell imaging, L-leucine was found to remarkably increase axonal length and growth velocity after axotomy. We also verified that L-leucine enhanced p-mTOR/p-S6K activation in neurons by testing with an mTOR inhibitor, rapamycin. Thereafter, we investigated the effects of L-leucine on the spinal cord injury in vivo. A mouse model of spinal cord hemi-section was established, and L-leucine was administered by tail intravenous injection. Basso mouse scale values revealed that L-leucine could improve functional recovery after injury. It was also notable that L-leucine treatment promoted axon growth across chondroitin sulfate proteoglycan (CSPG) areas. Furthermore, we used CSPGs as inhibitory environmental cues and clarified that L-leucine significantly enhanced axonal outgrowth and regeneration by promoting p-mTOR and p-S6K activation. Therefore, our study is the first to report that L-leucine promotes axonal regeneration in vitro and in vivo and could be candidate drug for axonal re-growth and nervous functional recovery.

GIP-GIPR promotes neurite outgrowth of cortical neurons in Akt dependent manner.

The intrinsic capacity of axonal growth is varied among the neurons form different tissues or different developmental stages. In this study, we established an in vitro model to compare the axonal growth of neurons from embryonic 18 days, post-natal 1 day and post-natal 3 days rat. The E18 neurons showed powerful ability of neuritogenensis and axon outgrowth and the ability decreased rapidly along with development. The transcriptome profile of these neurons revealed a set of genes positively correlated with the capacity of neurite outgrowth. Glucose-dependent insulinotropic polypeptide receptor (GIPR) is identified as a gene to promote neurite outgrowth, which was approved by siRNA knock down assay in E18 neuron. Glucose-dependent insulinotropic polypeptide (GIP), a ligand of GIPR secreted from enteroendocrine K cells, is well-known for its role in nutrient sensing and intake. To verify the effect of GIP-GIPR signal on neurite outgrowth, we administrated GIP to stimulate the E18 neurons, the results showed that GIP significantly improved extension of axon. We further revealed that GIP increased Rac1/Cdc42 phosphorylation in Akt dependent manner. In summary, our study established an in vitro model to screen the genes involved in neurite outgrowth, and we provided mechanical insight on the GIP-GIPR axis to promote axonal outgrowth.

Comparison of neural stem/progenitor cells from adult Gecko japonicus and mouse spinal cords.

The properties and number of neural stem cells (NSCs) in neural tissue are important issues for the regenerative capacity of the spinal cord in different organisms or developmental stages. In this study, we investigated the self-renewal and differentiation potential of NSCs from adult spinal cords of adult geckos (Gecko japonicus) and mice. The sphere forming ratio of mouse NSCs was higher than that of gecko NSCs, and the sphere forming time of mouse NSCs was shorter as well. In addition, serum-induced differentiation of NSCs gave rise to more ß-tubulin III (TUBB3)-positive progeny in geckos, whereas NSCs gave rise to more glial fibrillary acidic protein (GFAP)-positive cells in mice. We further conducted single sphere RNA-seq for both gecko and mouse NSCs, and transcriptome data revealed that purified NSC populations form either geckos or mice are heterogeneous and stay at various differentiated stages even with similar appearance. Mouse NSCs expressed more glial markers and gecko NSCs expressed more neuronal markers, which is consistent with cell fate determination of mouse and gecko NSCs in differentiation assays.

Development and evaluation of a convenient immunochromatographic strip test for rapid detection of cyprinid herpesvirus 2 (CyHV-2).

Cyprinid herpesvirus 2 (CyHV-2) has become a serious threat to the gibel carp Carassius auratus gibelio industry and has led to enormous losses worldwide. We have therefore developed an immunochromatographic strip (ICS) to enable rapid on-site detection of CyHV-2 by aquaculture facility staff. The ICS employs 2 monoclonal antibodies (MAbs 2C3-1E6 and 3H2-1G5) against the ORF25 protein, a CyHV-2 membrane protein, as the capture and detection antibodies, respectively. Indirect immunofluorescence assay (IIFA) and Western blotting of CyHV-2-infected fathead minnow cells indicated that the 2 MAbs could specifically bind CyHV-2 by recognizing ORF25 antigen. Sandwich ELISA showed that the detection limit of ORF25 protein halved when MAb 2C3-1E6 served as the capture antibody compared to MAb 3H2-1G5. The test for detecting purified CyHV-2 using the ICS could be completed in 10 min and the sensitivity was 1 µg ml-1. Sensitivity of the ICS remained stable following storage at 4, 25 and 37°C for 6 mo. Tissue homogenate from gibel carp with and without obvious gill hemorrhages was subjected to CyHV-2 detection using the ICS: the results were in good accordance with conventional PCR. Our ICS does not require highly trained technicians or specialized equipment, making it suitable for rapid diagnosis of CyHV-2 infection both in the laboratory and in the field.

Development of monoclonal antibodies against serum immunoglobulins from gibel carp (Carassius auratus gibelio) and their applications in serodiagnosis of inapparent infection and evaluation of vaccination strategies.

The disease outbreak caused by viral infection and bacterial pathogens has hampered the sustainable development of the gibel carp (Carassius auratus gibelio) industry, lack of monoclonal antibodies against serum immunoglobulin (Ig) of gibel carp has impeded the development of nonfatal immunoassays in detection of pathogen infection and understanding of fish immune response post vaccination. In the present study, serum Ig of gibel carp was purified by a combination of salting-out and DEAE Sepharose Column chromatography. The purified Ig had an apparent molecular weight of 74 kDa and 24 kDa in SDS-PAGE. Three monoclonal antibodies (MAbs) against Ig, designed as 2F4-1G10, 3H3-1E8 and 7H11-1C8, were developed with purified Ig preparations, which were selected on the basis of the indirect enzyme-linked immunosorbent assay (ELISA). Western blotting showed that MAbs 2F4-1G10 and 7H11-1C8 reacted with the heavy chain of IgM, while MAb 3H3-1E8 showed a reaction with the light chain. MAb 7H11-1C8 could react with surface Ig-positive (sIg+) lymphocytes under indirect immunofluorescence assay. Fluorescence-activated cell sorter analysis revealed that the percentage of sIg + lymphocytes were 32.68% in peripheral blood and 12.13% in pronephros. MAb 7H11-1C8 was proven to be effective in detecting the Cyprinid Herpesvirus 2-specific serum Ig, and determining the levels of Aeromonas hydrophila specific Ig in serum and immune organs under different vaccination strategies.

FY-3D MERSI On-Orbit Radiometric Calibration from the Lunar View.

Limited by the on-orbital calibration capability, scaling the measured radiance in accuracy and stability is challenging for the Earth observation satellites in the reflective solar bands (RSBs). Although the lunar calibration is a well-developed technique in the RSBs, limited work has been done for Chinese Earth observation satellites. To improve the on-orbital calibration performance, the advanced MEdium Resolution Spectral Imager (MERSI II), which is the primary payload of the fourth satellite of the Fengyun 3 Series (FY-3D), expands the space view angle of the imager in order to capture better lunar images. In this study, we propose an absolute radiometric calibration method based on the FY-3D/MERSI lunar observation data. A lunar irradiance model named ROLO/GIRO has been used together with the necessary data procedures, including dark current count estimation, single pixel irradiance calculation, and full disk lunar irradiance calculation. The calibration coefficients obtained by the lunar calibration are compared with the pre-launch laboratory calibration. The results show that the deviations between the two calibration procedures are in a reasonable range in general. However, a relatively high non-linear response was found in the low energy incidence for some detectors, which leads to the large deviation in the corresponding bands. This study explored an ideal and independent method to validate MERSI on-orbit radiometric performance. The lunar calibration practiced for MERSI also gave a valuable example that can be recommended to the other Chinese Earth observation satellites.

Inhibition of microRNA-132 attenuates inflammatory response and detrusor fibrosis in rats with interstitial cystitis via the JAK-STAT signaling pathway.

Interstitial cystitis (IC) is a heterogeneous syndrome with unknown etiology, and microRNAs (miRs) were found to be involved in IC. In our study, we aim to explore the role of miR-132 in the inflammatory response and detrusor fibrosis in IC through the Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway in rat models. A rat model of IC was established and treated with the miR-132 mimic, miR-132 inhibitor, and/or JAK-STAT signaling pathway inhibitor AG490. Enzyme-linked immunosorbent assay was applied to measure the expression of interleukin (IL)-6, IL-10, interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α), and intercellular adhesion molecule-1 (ICAM-1). The urodynamic test was performed to assess urodynamic parameters, and reverse transcription quantitative polymerase chain reaction and Western blot analysis for the expression of miR-132, STAT4, suppressors of cytokine signaling 3 (SOCS3), JAK2, vascular endothelial growth factor (VEGF), IFN-γ, and TNF-α. IC rats treated with miR-132 inhibitor and AG490 had decreased collagen fiber, inflammatory cell infiltration, and mast cells, lower expression of IL-6, IL-10, IFN-γ, TNF-α, ICAM-1, collagens I and III, and alleviated urodynamic parameters and decreased expression of STAT4, VEGF, JAK2, IFN-γ, TNF-α, and increased expression of SOCS3. Taken together, our data indicate that downregulation of miR-132 alleviates inflammatory response and detrusor fibrosis in IC via the inhibition of the JAK-STAT signaling pathway.

Exosomal and extracellular HMGB1 have opposite effects on SASH1 expression in rat astrocytes and glioma C6 cells.

Exosomes are a type of extracellular vesicles derived from cells and mediators of intercellular communication. Different cell types have their own unique exosomes for exchanging information. We previously found that SASH1, a tumor suppressor, was lowly expressed or absent in glioma tissues and glioma C6 cells, but the structure and function of the corresponding exosomes had been unclear. Hence, we aimed to investigate whether exosomes generated from normal glial cells and glioma cells form different protein patterns and whether those derived from normal glial cells affect SASH1 expression in glioma cells. We collected exosomes from astrocytes and C6 cells and identified their exosomal proteins through mass spectrometry. We also performed gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses, whose results showed that both the total and unique exosomal proteins from each cell type were similar. Moreover, the KEGG analysis revealed different clusters of unique exosomal proteins in glial cells and glioma cells. In the normal glial cells, the top clusters were mainly involved in processes with RNA transcripts and proteins, whereas in glioma cells the clusters were attributed to PI3K-Akt signaling, cell adhesion, and cancer-related pathways. Western blot analysis showed that HMGB1 exists in exosomes derived from cultured astrocytes, although its expression was higher in glioma C6 cells. Furthermore, we found that exosomes extracted from astrocytes could increase SASH1 expression in C6 cells (P = 0.040), whereas those derived from HMGB1-depleted astrocytes could not (P = 0.6133). The expression levels of SASH1 decreased after the addition of extracellular recombinant HMGB1 protein, whereas that of TLR4 increased. Our study is the first to demonstrate that HMGB1 plays different roles depending on its form: as an extracellular protein, HMGB1 decreases SASH1 expression, but as an exosomal protein, HMGB1 increases SASH1 expression. Nevertheless, the mechanism, which partly depends on the TLR4 pathway, behind these opposing effects requires further study. Our novel findings on the structure-dependent roles of the cytokine HMGB1 in promoting or inhibiting cancer provide a fresh insight into the interactions of cancer cells with the microenvironment.

Congenital asplenia due to a tlx1 mutation reduces resistance to Aeromonas hydrophila infection in zebrafish.

It is documented that tlx1, an orphan homeobox gene, plays critical roles in the regulation of early spleen developmental in mammalian species. However, there is no direct evidence supporting the functions of tlx1 in non-mammalian species, especially in fish. In this study, we demonstrated that tlx1 is expressed in the splenic primordia as early as 52 hours post-fertilization (hpf) in zebrafish. A tlx1-/- homozygous mutant line was generated via CRISPR/Cas9 to elucidate the roles of tlx1 in spleen development in zebrafish. In the tlx1-/- background, tlx1-/- cells persisted in the splenic primordia until 52 hpf but were no longer detectable after 53 hpf, suggesting perturbation of early spleen development. The zebrafish also exhibited congenital asplenia caused by the tlx1 mutation. Asplenic zebrafish can survive and breed normally under standard laboratory conditions, but the survival rate of animals infected with Aeromonas hydrophila was significantly lower than that of wild-type (WT) zebrafish. In asplenic zebrafish, the mononuclear phagocyte system was partially impaired, as demonstrated by retarded b7r expression and reduced ccr2 expression after injection with an inactivated A. hydrophila vaccine. Furthermore, the expression of MHCII/IgM was significantly reduced in the congenitally asplenic fish compared with that of the WT zebrafish. Taken together, our data suggest that tlx1 is a crucial regulator of spleen development in fish, as it is in mammals. We have also provided a new perspective for studying the role of the spleen during pathogen challenge in fish.