作者:Fan Feng, Lei Lei , Junqun Liao , Xiaomei Huang , Yong Shao
摘要:Purpose:Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy complication. However, the pathogenesis of ICP is currently unclear.Methods:We analyzed the placenta samples of 10 normal and 10 ICP pregnant women. the expressions of circ0060731, miR-21-5p, and their downstream target genes PDCD4, ESR1, and apoptotic protein cleaved-caspase3 were detected in the cell model.Results:The expression of Circ_0060731, PDCD4, ESR1, and caspase-3 was higher in the ICP placenta tissue than in the control group, and the expression of miR-21-5p was lower in the ICP group than in the control group. In HTR8/Svneo cells treated with TCA, the expression/levels of Circ_0060731, PDCD4, ESR1, and caspase-3 were significantly higher in the ICP group than in the control group, and miR-21-5p was significantly lower in the ICP group than in the control group. Lentiviral knockdown of miR-21-5p significantly increased the expressions of its downstream genes of PDCD4 and ESR1, and also increased cell apoptosis. Overexpression of miR-21-5p significantly reduced the expression of PDCD4 and ESR1 and reduced cell apoptosis. The dual-luciferase experiment showed that both PDCD4 and ERS1 were the target genes of miR-21-5p.Conclusion:Circ_0060731 mediated miR-21-5p-PDCD4/ESR1 pathway could induce apoptosis of placental trophoblasts in intrahepatic cholestasis of pregnancy.Keywords:Apoptosis; Circ_0060731; Intrahepatic cholestasis of pregnancy; MiR-21–5p.
摘要:S-ribonuclease (S-RNase)-based self-incompatibility (SI) mechanisms have been extensively studied in Solanaceae, Rosaceae and Plantaginaceae. S-RNase-based SI is controlled by two closely related genes,S-RNaseandS-locus F-box(SLF), located at a polymorphic S-locus. In the SI system, the SCF-type (SKP1-CUL1-F-box-RBX1) complex functions as an E3 ubiquitin ligase complex for ubiquitination of non-self S-RNase. Pummelo (Citrus grandis) and several mandarin cultivars are suggested to utilize an S-RNase-based SI system. However, the molecular mechanism of the non-S-factors involved in the SI reaction is not straightforward inCitrus. To investigate the SCF-type E3 complex responsible for the SI reaction in mandarin, SLF, SKP1-like and CUL1 candidates potentially involved in the SI reaction of ‘Wuzishatangju’ (Citrus reticulataBlanco) were identified based on the genome-wide identification and expression analyses. Sixteen pollen-specificF-boxgenes (CrFBX1-CrFBX16), one pollen-specificSKP1-likegene (CrSKP1-e) and twoCUL1genes (CrCUL1AandCrCUL1B) were identified and cloned from ‘Wuzishatangju’. Yeast two-hybrid (Y2H) and in vitro binding assays showed that five CrFBX proteins could bind to CrSKP1-e, which is an ortholog of SSK1 (SLF-interacting-SKP1-like), a non-S-factor responsible for the SI reaction. Luciferase complementation imaging (LCI) and in vitro binding assays also showed that CrSKP1-e interacts with the N-terminal region of both CrCUL1A and CrCUL1B. These results indicate that CrSKP1-e may serve as a functional member of the SCF-type E3 ubiquitin ligase complex in ‘Wuzishatangju’.
摘要:Background:46,XY disorders/differences of sex development (46,XY DSD) are congenital conditions that result from abnormal gonadal development (gonadal dysgenesis) or abnormalities in androgen synthesis or action. During early embryonic development, several genes are involved in regulating the initiation and maintenance of testicular or ovarian-specific pathways. Recent reports have shown thatMAP3K1genes mediate the development of the 46,XY DSD, which present as complete or partial gonadal dysgenesis. Previous functional studies have demonstrated that someMAP3K1variants result in the gain of protein function. However, data on possible mechanisms ofMAP3K1genes in modulating protein functions remain scant.Methods:This study identified a Han Chinese family with the 46,XY DSD. To assess the history and clinical manifestations for the 46,XY DSD patients, the physical, operational, ultra-sonographical, pathological, and other examinations were performed for family members. Variant analysis was conducted using both trio whole-exome sequencing (trio WES) and Sanger sequencing. On the other hand, we generated transiently transfected testicular teratoma cells (NT2/D1) and ovary-derived granular cells (KGN), with mutant or wild-typeMAP3K1gene. We then performed functional assays such as determination of steady-state levels of gender related factors, protein interaction and luciferase assay system.Results:Two affected siblings were diagnosed with 46,XY DSD. Our analysis showed a missense c.556A > G/p.R186G variant in theMAP3K1gene. Functional assays demonstrated that the MAP3K1R186Gvariant was associated with significantly decreased affinity to ubiquitin (Ub; 43–49%) and increased affinity to RhoA, which was 3.19 ± 0.18 fold, compared to MAP3K1. The MAP3K1R186Gled to hyperphosphorylation of p38 and GSK3β, and promoted hyperactivation of the Wnt4/β-catenin signaling. In addition, there was increased recruitment of β-catenin into the nucleus, which enhanced the expression of pro-ovarian transcription factorFOXL2gene, thus contributing to the 46,XY DSD.Conclusion:Our study identified a missenseMAP3K1variant associated with 46,XY DSD. We demonstrated that MAP3K1R186Gvariant enhances binding to the RhoA and improves its own stability, resulting in the activation of the Wnt4/β-catenin/FOXL2 pathway. Taken together, these findings provide novel insights into the molecular mechanisms of 46,XY DSD and promotes better clinical evaluation.
摘要:Mammalian fertility is reduced during heat exposure in the summer, but is regained as temperatures decrease in the autumn again. However, the mechanism underlying the phenomenon remains unknown. We investigated heat stress tolerance of germ cells and their surrounding somatic cells, and discovered that microRNA ssc-ca-1 was upregulated after heat stress in cultured porcine granulosa cells (GCs), but not in serum-starved GCs. Ssc-ca-1 inhibited heat shock protein 70 (Hsp70) expression through its 3′- and 5′-UTRs. AlthoughHsp70mRNA transcription was induced in GCs byin vivoexposure to heat in the summer, ssc-ca-1 inhibited Hsp70 expression. In ovarian cultures, heat stress-induced Hsp70 expression in primordial but not in growing follicles; ssc-ca-1 expression did not change in primordial follicles, but increased in growing follicles. Consistently, ssc-ca-1 was present in testicular cells and exhibited the same function as in ovarian cells. It modulated the different Hsp70 expression between spermatogonial stem cells and Sertoli cells after scrotal heat stress. This mechanism is of relevance to mammalian fertility in parts of the world dominated by heat stress associated with global climate change.
摘要:NAC protein is a large plant specific transcription factor family, which plays important roles in the response to abiotic stresses. However, the regulation mechanism of most NAC proteins in drought stress remains to be further uncovered. In this study, we elucidated the molecular functions of a NAC protein, GhirNAC2, in response to drought stress in cotton.GhirNAC2was greatly induced by drought and phytohormone abscisic acid (ABA). Subcellular localization demonstrated that GhirNAC2 was located in the nucleus. Co-suppression ofGhirNAC2in cotton led to larger stomata aperture, elevated water loss and finally reduced transgenic plants tolerance to drought stress. Furthermore, the endogenous ABA content was significantly lower inGhirNAC2-suppressed transgenic plant leaves compared to wild type.in vivoandin vitrostudies showed that GhirNAC2 directly binds to the promoter ofGhNCED3a/3c, key genes in ABA biosynthesis, which were both down-regulated inGhirNAC2-suppressed transgenic lines. Transient silencing ofGhNCED3a/3calso significantly reduced the resistance to drought stress in cotton plants. However, ectopic expression ofGhirNAC2in tobacco significantly enhanced seed germination, root growth and plant survival under drought stress. Taken together,GhirNAC2plays a positive role in cotton drought tolerance, which functions by modulating ABA biosynthesis and stomata closure via regulatingGhNCED3a/3cexpression.
作者:Wei Gong, Jiancheng Xu, Guangchao Wang, Dan Li, Qimin Zhan
摘要:Objective:Increasing evidence has demonstrated that ZNF292 plays a suppressive role in cancer, however, little is known about its function and exact mechanism in esophageal squamous cell carcinoma (ESCC).Methods:Bioinformatic analysis and immunohistochemistry (IHC) were performed to analyze the role of ZNF292 in affecting the prognosis of ESCC. Cell proliferation and colony formation ability assays were performed to analyze cell growth after inferring the expression of ZNF292. Flow cytometry was used to analyze changes in the cell cycle upon the depletion of ZNF292. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis were used to determine the alteration of cell cycle related RNAs and proteins after knocking down ZNF292. MG-132, cycloheximide (CHX) treatment experiments were performed to analyze the change and half-life time of P27 after knockdown of ZNF292. Chromatin immunoprecipitation (ChIP) and luciferase reporter assays were used to analyze the transcriptional regulation of SKP2 by ZNF292.Results:We report that low expression of ZNF292 is associated with poor prognosis, and ZNF292 emerges to be highly expressed in adjacent and normal tissues rather than tumor tissues in ESCC. Knockdown of ZNF292 significantly boosts cell growth and S phase entry in ESCC cells. ZNF292 depletion will decrease the expression and half-life time of P27, while knockdown of SKP2 will result in elevated expression of P27. ZNF292 can bind to the promoter region of SKP2, and knockdown of ZNF292 will boost the expression of SKP2.Conclusions:Knockdown of ZNF292 mediates G1/S cell cycle procession by activating SKP2/P27 signaling in ESCC cells. ZNF292 knockdown promotes SKP2 expression at the transcriptional level, thereby boosting P27 ubiquitin-degradation, and eventually facilitating the S phase entrance.Keywords:ESCC; SKP2; ZNF292; cell cycle.
摘要:S-ribonuclease (S-RNase)-based self-incompatibility (SI) mechanisms have been extensively studied in Solanaceae, Rosaceae and Plantaginaceae. S-RNase-based SI is controlled by two closely related genes,S-RNaseandS-locus F-box(SLF), located at a polymorphic S-locus. In the SI system, the SCF-type (SKP1-CUL1-F-box-RBX1) complex functions as an E3 ubiquitin ligase complex for ubiquitination of non-self S-RNase. Pummelo (Citrus grandis) and several mandarin cultivars are suggested to utilize an S-RNase-based SI system. However, the molecular mechanism of the non-S-factors involved in the SI reaction is not straightforward inCitrusBlanco) were identified based on the genome-wide identification and expression analyses. Sixteen pollen-specificF-boxgenes (CrFBX1-CrFBX16), one pollen-specificSKP1-likegene (CrSKP1-e) and twoCUL1genes (CrCUL1A) were identified and cloned from ‘Wuzishatangju’. Yeast two-hybrid (Y2H) and in vitro binding assays showed that five CrFBX proteins could bind to CrSKP1-e, which is an ortholog of SSK1 (SLF-interacting-SKP1-like), a non-S-factor responsible for the SI reaction. Luciferase complementation imaging (LCI) and in vitro binding assays also showed that CrSKP1-e interacts with the N-terminal region of both CrCUL1A and CrCUL1B. These results indicate that CrSKP1-e may serve as a functional member of the SCF-type E3 ubiquitin ligase complex in ‘Wuzishatangju’.
摘要:Alphaherpesviruses are large dsDNA viruses with an ability to establish persistent infection in hosts, which rely partly on their ability to evade host innate immune responses, notably the type I IFN response. However, the relevant molecular mechanisms are not well understood. In this study, we report the UL42 proteins of alphaherpesvirus pseudorabies virus (PRV) and HSV type 1 (HSV1) as a potent antagonist of the IFN-I–induced JAK-STAT signaling pathway. We found that ectopic expression of UL42 in porcine macrophage CRL and human HeLa cells significantly suppresses IFN-α–mediated activation of the IFN-stimulated response element (ISRE), leading to a decreased transcription and expression of IFN-stimulated genes (ISGs). Mechanistically, UL42 directly interacts with ISRE and interferes with ISG factor 3 (ISGF3) from binding to ISRE for efficient gene transcription, and four conserved DNA-binding sites of UL42 are required for this interaction. The substitution of these DNA-binding sites with alanines results in reduced ISRE-binding ability of UL42 and impairs for PRV to evade the IFN response. Knockdown of UL42 in PRV remarkably attenuates the antagonism of virus to IFN in porcine kidney PK15 cells. Our results indicate that the UL42 protein of alphaherpesviruses possesses the ability to suppress IFN-I signaling by preventing the association of ISGF3 and ISRE, thereby contributing to immune evasion. This finding reveals UL42 as a potential antiviral target.
作者:Xuan Wang, Mara Lennard Richard, Pengfei Li, Brittany Henry, Steven Schutt, Xue-Zhong Yu, Hongkuan Fan, Weiru Zhang, Gary Gilkeson, Xian K Zhang
摘要:Friend leukemia virus integration 1 (Fli-1) is an ETS transcription factor and a critical regulator of inflammatory mediators, including MCP-1, CCL5, IL-6, G-CSF, CXCL2, and caspase-1. GM-CSF is a regulator of granulocyte and macrophage lineage differentiation and a key player in the pathogenesis of inflammatory/autoimmune diseases. In this study, we demonstrated that Fli-1 regulates the expression of GM-CSF in both T cells and endothelial cells. The expression of GM-CSF was significantly reduced in T cells and endothelial cells when Fli-1 was reduced. We found that Fli-1 binds directly to the GM-CSF promoter using chromatin immunoprecipitation assay. Transient transfection assays indicated that Fli-1 drives transcription from the GM-CSF promoter in a dose-dependent manner, and mutation of the Fli-1 DNA binding domain resulted in a significant loss of transcriptional activation. Mutation of a known phosphorylation site within the Fli-1 protein led to a significant increase in GM-CSF promoter activation. Thus, direct binding to the promoter and phosphorylation are two important mechanisms behind Fli-1-driven activation of the GM-CSF promoter. In addition, Fli-1 regulates GM-CSF expression in an additive manner with another transcription factor Sp1. Finally, we demonstrated that a low dose of a chemotherapeutic drug, camptothecin, inhibited expression of Fli-1 and reduced GM-CSF production in human T cells. These results demonstrate novel mechanisms for regulating the expression of GM-CSF and suggest that Fli-1 is a critical druggable regulator of inflammation and immunity.
摘要:Radiation-induced lung injury is a common late side effect of thoracic radiotherapy. Endothelial dysfunction following leukocytes infiltration is a prominent feature in this process. Here, we established a clinical-mimicking mouse model of radiation-induced lung injury and found the activity of phosphatase Shp2 was elevated in endothelium after injury. Endothelium-specific Shp2 deletion mice showed relieved collagen deposition along with disrupted radiation-induced Jag1 expression in the endothelium. Furthermore, endothelium-derived Jag1 activated the alternative activation of macrophagesinvitroandinvivoby paracrine Notch signaling. Consistently, the Notch pathway was significantly activated by chest irradiation in the peripheral blood leukocytes of patients with cancer. Collectively, our work demonstrates that Shp2 participates in the radiation-induced endothelial dysfunction and subsequently inflammatory microenvironment producing during radiation-induced lung injury. Our findings indicate Shp2 as a potential target for radiation-induced lung injury and provide another way for endothelium to participate in the pathological process of radiation-induced lung injury.