Dorsomorphin induces cancer cell apoptosis and sensitizes cancer cells to HSP90 and proteasome inhibitors by reducing nuclear heat shock factor 1 levels

Objective: Heat shock factor 1(HSF1), a transcriptional regulator of heat shock proteins(HSPs), is an attractive therapeutic target for cancer. However, only a few HSF1 inhibitors have been identified so far.Methods: The mRNA and protein levels of HSF1, HSPs, cleaved PARP, and phosphorylated HSF1 were examined by real-time PCR and Western blot. Forced expression, RNA interference, and immunofluorescence assay were used for mechanistic studies.Cell viability and apoptosis were measured by WST-8 assay and flow cytometry, respectively. Xenograft studies were performed in nude mice to evaluate the effect of dorsomorphin and an HSP90 inhibitor on tumor growth.Results: Dorsomorphin suppressed multiple stimuli-induced and constitutive HSPs expression in cancer cells. Mechanistic studies revealed that dorsomorphin reduced heat-induced HSP expression independent of adenosine monophosphate activated protein kinase. Dorsomorphin reduced heat-stimulated HSF1 Ser320 phosphorylation and nuclear translocation, as well as resting nuclear HSF1 levels in cancer cells. Dorsomorphin induced cancer cell apoptosis by inhibiting HSF1 expression. A structure-activity study revealed that the 4-pyridyl at the 3-site of the pyrazolo [1, 5-a]pyrimidine ring is critical for the anti-HSF1 activities of dorsomorphin. Dorsomorphin sensitized cancer cells to HSP90 and proteasome inhibitors and inhibited HSP70 expression induced by these inhibitors in vitro. In tumor-bearing nude mice, dorsomorphin enhanced HSP90 inhibitor-induced cancer cell apoptosis, tumor growth inhibition, and HSP70 expression.Conclusions: Dorsomorphin is an HSF1 inhibitor. It induces cancer cell apoptosis, sensitizes cancer cells to both HSP90 and proteasome inhibitors, and suppresses HSP upregulation by these drugs, which may prevent the development of drug resistance.Hence, dorsomorphin and its derivates may serve as potential precursors for developing drugs against cancer.

ISA 61 VG佐剂增强单核细胞增生李斯特氏菌灭活疫苗的保护性免疫应答

单核细胞增生李斯特氏菌(Listeria monocytogenes,Lm)是重要的人兽共患李斯特氏菌病的致病菌,疫苗免疫是预防该病原菌感染的有效手段之一。本研究研制了添加矿物油佐剂MontanideTM ISA61VG的新型灭活细菌疫苗,并对其安全性和免疫应答特性进行了研究。结果表明,ISA 61 VG佐剂疫苗具有较好的安全性;诱导小鼠产生的抗李斯特氏菌溶血素O抗体滴度以及IgG2a/IgG1比值显著高于无佐剂免疫组;在致死剂量Lm攻毒下,能对小鼠提供100%的免疫保护。因此,ISA 61VG佐剂能显著增强灭活疫苗诱导宿主产生体液免疫和细胞免疫应答的能力,从而提高灭活疫苗的保护性免疫应答作用,是预防人和动物Lm感染的潜在疫苗候选株。

Natural variations of ZmSRO1d modulate the trade-off between drought resistance and yield by affecting ZmRBOHC-mediated stomatal ROS production in maize

While crop yields have historically increased,drought resistance has become a major concern in the context of global climate change.The trade-off between crop yield and drought resistance is a common phenomenon;however,the underlying molecular modulators remain undetermined.Through genome-wide association study,we revealed that three non-synonymous variants in a drought-resistant allele of ZmSRO1d-R resulted in plasma membrane localization and enhanced mono-ADP-ribosyltransferase activity of ZmSRO1d toward ZmRBOHC,which increased reactive oxygen species(ROS)levels in guard cells and promoted stomatal closure.ZmSRO1d-R enhanced plant drought resilience and protected grain yields under drought conditions,but it led to yield drag under favorable conditions.In contrast,loss-of-function mutants of ZmRBOHC showed remarkably increased yields under well-watered conditions,whereas they showed compromised drought resistance.Interestingly,by analyzing 189 teosinte accessions,we found that the ZmSRO1d-R allele was present in teosinte but was selected against during maize domestication and modern breeding.Collectively,our work suggests that the allele frequency reduction of ZmSRO1d-R in breeding programs may have compromised maize drought resistance while increased yields.Therefore,introduction of the ZmSRO1d-R allele into modern maize cultivars would contribute to food security under drought stress caused by global climate change.

Rare inherited missense variants of POGZ associate with autism risk and disrupt neuronal development

Excess de novo likely gene-disruptive and missense variants within dozens of genes have been identified in autism spectrum disorder(ASD)and other neurodevelopmental disorders.However,many rare inherited missense variants of these high-risk genes have not been thoroughly evaluated.In this study,we analyzed the rare missense variant burden of POGZ in a large cohort of ASD patients from the Autism Clinical and Genetic Resources in China(ACGC)and further dissected the functional effect of diseaseassociated missense variants on neuronal development.Our results showed a significant burden of rare missense variants in ASD patients compared to the control population(P=4.6×10-5,OR=3.96),and missense variants in ASD patients showed more severe predicted functional outcomes than those in controls.Furthermore,by leveraging published large-scale sequencing data of neurodevelopmental disorders(NDDs)and sporadic case reports,we identified 8 de novo missense variants of POGZ in NDD patients.Functional analysis revealed that two inherited,but not de novo,missense variants influenced the cellular localization of POGZ and failed to rescue the defects in neurite and dendritic spine development caused by Pogz knockdown in cultured mouse primary cortical neurons.Significantly,L1CAM,an autism candidate risk gene,is differentially expressed in POGZ deficient cell lines.Reduced expression of L1cam was able to partially rescue the neurite length defects caused by Pogz knockdown.Our study showed the important roles of rare inherited missense variants of POGZ in ASD risk and neuronal development and identified the potential downstream targets of POGZ,which are important for further molecular mechanism studies.

Dysregulated CRMP Mediates Circadian Deficits in a Drosophila Model of Fragile X Syndrome

Fragile X syndrome(FXS)is the leading inherited cause of intellectual disability,resulting from the lack of functional fragile X mental retardation protein(FMRP),an mRNA binding protein mainly serving as a translational regulator.Loss of FMRP leads to dysregulation of target mRNAs.The Drosophila model of FXS show an abnormal circadian rhythm with disruption of the output pathway downstream of the clock network.Yet the FMRP targets involved in circadian regulation have not been identified.Here,we identified collapsing response mediator protein(CRMP)mRNA as a target of FMRP.Knockdown of pan-neuronal CRMP expression ameliorated the circadian defects and abnormal axonal structures of clock neurons(ventral lateral neurons)in dfmr1 mutant flies.Furthermore,specific reduction of CRMP in the downstream output insulin-producing cells attenuated the aberrant circadian behaviors.Molecular analyses revealed that FMRP binds with CRMP mRNA and negatively regulates its translation.Our results indicate that CRMP is an FMRP target and establish an essential role for CRMP in the circadian output in FXS Drosophila.

Identification of a novel efficient transcriptional activation domain from Chinese fir(Cunninghamia lanceolata)

Direct manipulation of gene expression in vivo is a powerful approach for investigating biological systems and bioengineering in plants(Zhang et al.,2015;Zhao et al.,2015;Lowder et al.,2018).In the past decade,considerable progress has been made in developing techniques for gene targeting.

In vitro assembly of Ebola virus nucleocapsidlike complex expressed in E. coil

Ebola virus （EBOV） harbors an RNA genome encapsi- dated by nucleoprotein （NP） along with other viral pro- teins to form a nucleocapsid complex. Previous Cryo- eletron tomography and biochemical studies have shown the helical structure of EBOV nucleocapsid at nanometer resolution and the first 450 amino-acid of NP （NP△451-739） alone is capable of forming a helical nucleocapsid-Iike complex （NLC）. However, the struc- tural basis for NP-NP interaction and the dynamic pro- cedure of the nucleocapsid assembly is yet poorly understood. In this work, we, by using an E. coli expression system, captured a series of images of NP△451-739 conformers at different stages of NLC assembly by negative-stain electron microscopy, which allowed us to picture the dynamic procedure of EBOV nucleocapsid assembly. Along with further biochemical studies, we showed the assembly of NLC is salt-sensi- tive, and also established an indispensible role of RNA in this process. We propose the diverse modes of NLC elongation might be the key determinants shaping the plasticity of EBOV virions. Our findings provide a new model for characterizing the self-oligomerization of viral nucleoproteins and studying the dynamic assembly process of viral nucleocapsid in vitro.