Downregulation of cold-inducible RNA-binding protein activates mitogen-activated protein kinases and impairs spermatoRenic function in mouse testes

Cold-inducible RNA-binding protein （CIRP） is an RNA-binding protein that is expressed in normal testes and downregulated after heat stress caused by cryptorchidism, varicocele or environmental temperatures. The purpose of this study was to investigate the functions of CIRP in the testes. We employed RNAi technique to knock down the expression of CIRP in the testes, and performed haematoxylin and eosin staining to evaluate morphological changes following knockdown. Germ cell apoptosis was examined by terminal deoxynucleotidal transferase-mediated dUTP nick end labelling （TUNEL） assay, and mitogen-activated protein kinase （MAPK） signalling pathways were investigated by Western blotting to determine the possible mechanism of apoptosis. We found that using siRNA is a feasible and reliable method for knocking down gene expression in the testes. Compared to controls, the mean seminiferous tubule diameter （MSTD） and the thickness of the germ cell layers decreased following siRNA treatment, whereas the percentage of apoptotic seminiferous tubules increased. The p44/p42, p38 and SAPK/JNK MAPK pathways were activated after downregulation of CIRP. In conclusion, we discovered that downregulation of CIRP resulted in increased germ cell apoptosis, possibly viathe activation of the p44/p42, p38 and SAPK/JNK MAPK pathways.

Overinhibition of Mitogen-Activated Protein Kinase Inducing Tau Hyperphosphorylation

To reveal the relationship between mitogen-acti-vated protein kinase (MAPK)and tau phosphorylation, we used different concentration of PD98059, an inhibitor of MEK (MAPKkinase), to treat mice neuroblastma (N2a) cell line for 6 h. It showed that theactivity of MAPKdecreased in a dose-dependent manner. But Western blot and immunofluo-rescence revealed that justwhen the cells were treated with 16 mu mol/L PD98059, tau was hyperphosphorylated at Ser396/ 404 andSerl99/202 sites. We obtained the conclusion that overinhibited MAPK induced tauhyperphosphorylation at Ser396/404 and Serl99/202 sites.

Scutellarein Ameliorated Chondrocyte Inflammation and Osteoarthritis in Rats

Objective:Osteoarthritis(OA)is a degenerative joint disorder characterized by the gradual degradation of joint cartilage and local inflammation.This study aimed to investigate the anti-OA effect of scutellarein(SCU),a single-unit flavonoid compound obtained from Scutellaria barbata D.Don,in rats.Methods:The extracted rat chondrocytes were treated with SCU and IL-1β.The chondrocytes were divided into control group,IL-1βgroup,IL-1β+SCU 50µmol/L group,and IL-1β+SCU 100µmol/L group.Morphology of rat chondrocytes was observed by toluidine blue and safranin O staining.CCK-8 method was used to detect the cytotoxicity of SCU.ELISA,qRT-PCR,Western blotting,immunofluorescence,SAβ-gal staining,flow cytometry,and bioinformatics analysis were applied to evaluate the effect of SCU on rat chondrocytes under IL-1βintervention.Additionally,anterior cruciate ligament transection(ACL-T)was used to establish a rat OA model.Histological changes were detected by safranin O/fast green,hematoxylin-eosin(HE)staining,and immunohistochemistry.Results:SCU protected cartilage and exhibited anti-inflammatory effects via multiple mechanisms.Specifically,it could enhance the synthesis of extracellular matrix in cartilage cells and inhibit its degradation.In addition,SCU partially inhibited the nuclear factor kappa-B/mitogen-activated protein kinase(NF-κB/MAPK)pathway,thereby reducing inflammatory cytokine production in the joint cartilage.Furthermore,SCU significantly reduced IL-1β-induced apoptosis and senescence in rat chondrocytes,further highlighting its potential role in OA treatment.In vivo experiments revealed that SCU(at a dose of 50 mg/kg)administered for 2 months could significantly delay the progression of cartilage damage,which was reflected in a lower Osteoarthritis Research Society International(OARSI)score,and reduced expression of matrix metalloproteinase 13(MMP13)in cartilage.Conclusion:SCU is effective in the therapeutic management of OA and could serve as a potential candidate for future clinical drug therapy for OA.

水稻MAPK基因Os MPK4的克隆鉴定、蛋白表达和转基因载体构建

克隆鉴定了一个水稻促分裂原活化蛋白激酶（mitogen-activated protein kinases, MAPK）基因OsMPK4．OsMPK4基因cDNA全长1483bp，包含一个1131bp的开放阅读框，编码一个由376个氨基酸组成的蛋白，预测分子量为42．8kD．OsMPK4基因位于水稻第10号染色体上，由6个外显子和5个内含子组成．OsMPK4蛋白具有MAPK的11个保守结构域及磷酸化位点TEY模体．系统进化树分析表明，OsMPK4属于B组MAPK成员，与已知水稻MAPK蛋白有56％～74％的一致性．原核表达了OsMPK4基因，纯化获得重组OsMPK4融合蛋白，并构建OsMPK4的转基因双元载体，用于OsMPK4的生化功能及其生物学功能研究．

线粒体融合蛋白2及Ras-MAPK信号通路与乳腺癌的研究进展

线粒体融合蛋白2(Mfn2)是一种高度保守的跨膜GTP酶,由新鉴定的抑癌基因Mfn2编码,它的抗肿瘤作用跟丝裂原活化蛋白激酶(MAPK)信号通路有关。MAPK是Ras信号通路下游的一个主要支路,在细胞恶变和肿瘤浸润、转移过程中起着重要作用。本文对Mfn2的分子结构、调控机制及其在乳腺癌中与Ras-MAPK信号通路关系的最新研究进展作一综述。

Genome-wide evolution of MAPKs family and their expression in response to bacterial infection in seahorse Hippocampus erectus

Seahorses have evolved many unique biological traits,including a male brood pouch,the absence of caudal and pelvic fins,and the lack of spleen and gut-associated lymphatic tissue.The mitogenactivated protein kinases(MAPKs)are known to be involved in various important biological processes including growth,differentiation,immunity,and stress responses.Therefore,we hypothesized that the adaptive evolution and expression of the MAPK gene family in seahorse may differ from those of other teleost species.We identified positive selection sites in the erk2,erk5,jnk1,and p38αMAPK genes of the lined seahorse Hippocampus erectus and tiger-tailed seahorse Hippocampus comes.A novel expression profile of MAPK cascade genes was found in seahorse larvae during the first day after birth based on the RNA-seq data of H.erectus,which refl ected vital signs of immune response to its parental immune system.The expression patterns of the four positively selected MAPK genes were analyzed following the bacterial challenge of Vibrio fortis,revealing their upregulation pattern in brood pouch and other immune tissues.This study enriched our knowledge of the evolution of the H.erectus MAPK subfamilies,and could help better understanding the functional role of MAPKs in teleosts.

Serine659 in ClC-2-Target Site for Phosphorylation by MAPK

In order to further investigate the role of ClC-2（ClC=chloride-ion channel） played in the regulation of cell proliferation and differentiation, the capablity of ClC-2 phosphorylation catalyzed by mitogen-activated protein ki-nase（MAPK） was studied. A mutation of 659Ser to Ala（S659A） of the rabbit ClC-2 cDNA in the consensus sequence of MAPK phosphorylation was introduced by overlap extension polymerase chain reaction（PCR）. Recombinant vectors pGEX-4T-1/ClC-2-2CT and pGEX-4T-1/ClC-2CT（S659A） were constructed. They were transformed to E. coli BL21, expressed by isopropy-β-D-thiogalactoside（IPTG） induction, the recombinant proteins were subjected to purification by glutathione sepharose 4B affinity chromatography. In vitro phosphorylation of the fusion proteins catalyzed by MAPK was performed. The results show that fusion protein GST/ClC-2CT（wild type） can be phosphorylated by MAPK, and this phosphorylation can be restrained by the inhibitor p42/44MAPK, PD98095; while the phosphorylation level of fusion protein GST/ClC-2CT（S659A）（mutant） was significantly reduced. Therefore, ClC-2 can be phosphorylated by MAPK and the target site of the phosphorylation is most likely the 659Ser residue.

MAPKs represent novel therapeutic targets for gastrointestinal motility disorders

The number of patients suffering from symptoms associated with gastrointestinal(GI) motility disorders is on the rise. GI motility disorders are accompanied by alteration of gastrointestinal smooth muscle functions. Currently available drugs,which can directly affect gastrointestinal smooth muscle and restore altered smooth muscle contractility to normal,are not satisfactory for treating patients with GI motility disorders. We have recently shown that ERK1/2 and p38MAPK signaling pathways play an important role in the contractile response not only of normal intestinal smooth muscle but also of inflamed intestinal smooth muscle. Here we discuss the possibility that ERK1/2 and p38MAPK signaling pathways represent ideal targets for generation of novel therapeutics for patients with GI motility disorders.

Arabidopsis RNA polymerase Ⅱ C-terminal domain phosphatase-like 1 targets mitogen-activated protein kinase cascades to suppress plant immunity

Mitogen-activated protein kinase(MAPK) cascades play pivotal roles in plant defense against phytopathogens downstream of immune receptor complexes. The amplitude and duration of MAPK activation must be strictly controlled, but the underlying mechanism remains unclear. Here, we identified Arabidopsis CPL1(C-terminal domain phosphatase-like 1)as a negative regulator of microbe-associated molecular pattern(MAMP)-triggered immunity via a forward-genetic screen. Disruption of CPL1 significantly enhanced plant resistance to Pseudomonas pathogens induced by the bacterial peptide fg22. Furthermore, fg22-induced MPK3/MPK4/MPK6 phosphorylation was dramatically elevated in cpl1 mutants but severely impaired in CPL1 overexpression lines, suggesting that CPL1 might interfere with fg22-induced MAPK activation. Indeed, CPL1 directly interacted with MPK3 and MPK6, as well as the upstream MKK4 and MKK5. A firefy luciferase-based complementation assay indicated that the interaction between MKK4/MKK5 and MPK3/MPK6 was significantly reduced in the presence of CPL1. These results suggest that CPL1 plays a novel regulatory role in suppressing MAMP-induced MAPK cascade activation and MAMP-triggered immunity to bacterial pathogens.

不同分子质量阿胶组分对RAW264.7小鼠巨噬细胞的免疫调节作用

为了探究阿胶不同分子质量组分免疫活性的强弱,通过Superdex 75pg葡聚糖凝胶柱将阿胶分为分子质量<10 kDa、10~30 kDa、>30 kDa(F1、F2和F3)的3个组分,并比较它们刺激RAW264.7小鼠巨噬细胞释放NO和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的能力,然后以免疫活性最强组分为研究对象,研究其对巨噬细胞的激活作用及其机制。结果表明,在同等浓度下,F2组分比F1和F3组分能刺激巨噬细胞释放更多的NO和TNF-α,且其可以激活RAW264.7细胞,促进细胞释放活性氧(reactive oxygen species,ROS)和白细胞介素-6(interleukin-6,IL-6),说明阿胶中10~30 kDa的组分(F2)具有相对较强的免疫活性。此外,实时荧光定量PCR(quantitative real-time PCR,q-PCR)结果表明F2可以促进细胞TNF-α、IL-6、诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)和Toll样受体4(Toll-like receptor 4,TLR4)基因的表达,增加其在细胞内的mRNA含量,说明F2组分能够与TLR4受体结合,并且能够促进细胞中C-Jun氨基末端蛋白激酶(C-Jun N-terminal protein kainse,JNK)、细胞外调节蛋白激酶(extracellular regulated protein kinases,ERK)和P38蛋白的磷酸化,表明阿胶中F2组分可以通过丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)信号通路发挥免疫调节作用。以上研究结果将为优化阿胶的生产加工条件以制造出高免疫活性阿胶产品提供理论指导。

Anti-parkinsonian effects of octacosanol in 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-treated mice

Our previous research showed that octacosanol exerted its protective effects in 6-hydroxydopamine-induced Parkinsonian rats. The goal of this study was to investigate whether octacosanol would attenuate neurotoxicity in 1-methyl-4-phenyl-l,2,3,6 tetrahydropyridine （MPTP）-treated C57BL/6N mice and its potential mechanism. Behavioral tests, tyrosine hydroxylase immunohistochemistry and western blot were used to investigate the effects of octacosanol in a mouse model of Parkinson＇s disease. Oral administration of octacosanol （100 mg/kg） significantly improved behavioral impairments Jn mice treated by MPTP and markedly ameliorated morphological appearances of tyrosine hydroxylase-positive neuronal cells in the substantia nigra. Furthermore, octacosanol blocked MPTP-induced phosphorylation of p38MAPK and JNK, but not ERK1/2. These findings implicated that the protective effects afforded by octacosanol might be mediated by blocking the phosphorylation of p38MAPK and JNK on the signa transduction in vivo. Considering its excellent tolerability, octacosanol might be considered as a candidate agent for clinical application in treating Parkinson＇s disease.

Exogenous nerve growth factor protects the hypoglossal nerve against crush injury

Studies have shown that sensory nerve damage can activate the p38 mitogen-activated protein kinase（MAPK）pathway,but whether the same type of nerve injury after exercise activates the p38MAPK pathway remains unclear.Several studies have demonstrated that nerve growth factor may play a role in the repair process after peripheral nerve injury,but there has been little research focusing on the hypoglossal nerve injury and repair.In this study,we designed and established rat models of hypoglossal nerve crush injury and gave intraperitoneal injections of exogenous nerve growth factor to rats for 14 days.p38MAPK activity in the damaged neurons was increased following hypoglossal nerve crush injury;exogenous nerve growth factor inhibited this increase in acitivity and increased the survival rate of motor neurons within the hypoglossal nucleus.Under transmission electron microscopy,we found that the injection of nerve growth factor contributed to the restoration of the morphology of hypoglossal nerve after crush injury.Our experimental findings indicate that exogenous nerve growth factor can protect damaged neurons and promote hypoglossal nerve regeneration following hypoglossal nerve crush injury.

A cotton mitogen-activated protein kinase (GhMPK6) is involved in ABA-induced CAT1 expression and H_2O_2 production

The mitogen-activated protein kinase （MAPK） cascade is one of the a pivotal role in the regulation of stress and developmental signals in plants. major and evolutionally conserved signaling pathways and plays Here, we identified one gene, GhMPK6, encoding an MAPK protein in cotton. GFP fluorescence assay demonstrated that GhMAPK6 is a cytoplasm localized protein. Quantitative RT-PCR analysis revealed that mRNA accumulation of GhMPK6 was significantly promoted by abscisic acid （ABA）. Overexpression of GhMPK6 gene in the T-DNA insertion mutant atmkkl （SALK_015914） conferred a wild-type phenotype to the transgenic plants in response to ABA. Under ABA treatment, cotyledon greening/expansion in GhMPK6 transgenic lines and wild type was significantly inhibited, whereas the atmkkl mutant showed a relatively high cotyledon greening/expansion ratio. Furthermore, CAT1 expression and H2O2 levels in leaves of GhMPK6 transgenic lines and wild type were remarkably higher than those of atmkkl mutant with ABA treatment. Collectively, our results suggested that GhMPK6 may play an important role in ABA-induced CAT1 expression and H2O2 production.

丹参酮ⅡA对UVA诱导的HaCaT细胞凋亡的影响

以人自发性永生化角质形成细胞系(Ha Ca T)细胞为材料,通过CCK8和蛋白印迹法分别测定不同剂量长波紫外线(ultraviolet A,UVA)、不同浓度丹参酮ⅡA(tanshinoneⅡA,TSⅡA),以及UVA和TSⅡA共同作用下的细胞活力和促分裂素原活化蛋白激酶(mitogenactivated protein kinase,MAPK)信号通路蛋白(p38,JNK和Erk)磷酸化水平.结果表明:在10 J/cm2的UVA照射下,细胞活力为对照组的70%左右,在20 J/cm2的UVA照射下,细胞活力仅为对照组的55%左右;低浓度的TSⅡA在正常情况下对细胞活力无影响,高浓度(85μmol/L)TSⅡA处理组的细胞活力约为对照组的70%左右.与TSⅡA或UVA单独处理相比,二者共同作用下细胞活力大大降低且差异极其显著.UVA照射提高了MAPK信号通路中的p38和JNK磷酸化水平,但是对Erk磷酸化水平没有影响;而TSⅡA可以显著提高低辐射剂量(2 J/cm2)UVA诱导下的p38和JNK的磷酸化水平.这说明UVA促进Ha Ca T细胞凋亡是通过提高p38和JNK磷酸化水平来实现的;而TSⅡA可以提高p38和JNK磷酸化水平,进一步加速UVA诱导的Ha Ca T细胞凋亡.

Mitogen-activated protein kinase signal pathways play an important role in right ventricular hypertrophy of tetralogy of Fallot

Background Tetralogy of Fallot （TOF） is the most common malformation of children with an incidence of approximately 10% of congenital heart disease patients. There can be a wide spectrum to the severity of the anatomic defects, which include ventricular septal defect, aortic override, right ventricular outflow tract obstruction, and right ventricular hypertrophy. We examined the relationship between right ventricular hypertrophy in patients with TOF and the gene expression of factors in the mitogen-activated protein kinase （MAPK） signal pathway. Methods To gain insight into the characteristic gene（s） involved in molecular mechanisms of right ventricular hypertrophy in TOF, differential mRNA and micro RNA expression profiles were assessed using expression-based micro array technology on right ventricular biopsies from young TOF patients who underwent primary correction and on normal heart tissue. We then analyzed the gene expression of the MAPK signal pathway using reverse transcription-polymerase chain reaction （RT-PCR） in normals and TOF patients. Results Using the micro RNA chip V3.0 and human whole genome oligonucleotide microarray VI.0 to detect the gene expression, we found 1068 genes showing altered expression of at least two-fold in TOF patients compared to the normal hearts, and 47 micro RNAs that showed a significant difference of at least two-fold in TOF patients. We then analyzed these mRNAs and micro RNAs by target gene predicting software Microcosm Targets version 5.0, and determined those mRNA highly relevant to the right ventricular hypertrophy by RT-PCR method. There were obvious differences in the gene expression of factors in the MAPK signal pathway when using RT-PCR, which was consistent to the results of the cDNA microarray.Conclusion The upregulation of genes in the MAPK signal pathway may be the key events that contribute to right ventricular hypertrophy and stunted angiogenesis in patients with TOF.

Neuroprotective Effects of Raloxifene on Aβ_(25-35)-induced Damages in PC12 Cells via Mitogen-activated Protein Kinase Signaling Pathway

Objective To investigate the neuroprotective effects and the mechanism of this protection of raloxifene （RLX）, a selective estrogen receptor modulator.Methods MTT assay and flow cytometry with annexin V-FITC/PI staining were performed to evaluate the neuroprotective effects of RLX on Aβ25-35-induced toxicity. The potential mechanisms were studied by Western blotting in cultured rat pheochromocytoma cells （PC12 cells）.Results RLX（1 000 nmol/L）, in combination with Aβ25-35 （30 llmol/L）, increased the cell viability （P 〈0.001）, and reduced the number of apoptotic cells （P 〈0.05）. RLX attenuated Aβ25-35-induced loss of △ψm （P 〈0.01）. The changing of △ψm was similar to the variation of apoptosis. PD98059 （inhibitor of ERK1/2） inhibited the effects of RLX on cell viability and phosphorylation of cleaved caspase-9. No significant difference of cell viability or phosphorylation of cleaved caspase-9 had been found when PC12 cells were incubated with SB203580 （inhibitor of p38MAPK） or SP600125 （inhibitor of JNK）. Afl25.35 induced a time-dependent phosphorylation of p38MAPK and JNK. In PC12 cells treated solely with RLX, ERK1/2 was activated （P〈0.01）. In PC12 cells treated with Aβ25-35 and RLX, Aβ2545-induced phosphorylation of p38MAPK and JNK were inhibited （P〈0.01 and P〈0.001, respectively）.Conclusion RLX inhibited Af125.35-induced cell apoptosis by activating the ERK1/2 pathway in PC12 cells. RLX also attenuated Aβ25-35-induced activation of p38MAPK and JNK. The mitochondria pathway Was involved in this inhibitory effect.

Transthyretin—A Key Gene Involved in Regulating Learning and Memory in Brain, and Providing Neuroprotection in Alzheimer Disease via Neuronal Synthesis of Transthyretin Protein

Transthyretin (TTR), a carrier protein present in the liver and choroid plexus of the brain, has been shown to be responsible for binding thyroid hormone thyroxin (T4) and retinol in plasma and cerebrospinal fluid (CSF). TTR aids in sequestering of beta-amyloid peptides Aβ deposition, and protects the brain from trauma, ischemic stroke and Alzheimer disease (AD). Accordingly, hippocampal gene expression of TTR plays a significant role in learning and memory as well as in simulation of spatial memory tasks. TTR via interacting with transcription factor CREB regulates this process and decreased expression leads to memory deficits. By different signaling pathways, like MAPK, AKT, and ERK via Src, TTR provides tropical support through megalin receptor by promoting neurite outgrowth and protecting the neurons from traumatic brain injury. TTR is also responsible for the transient rise in intracellular Ca2+ via NMDA receptor, playing a dominant role under excitotoxic conditions. In this review, we tried to shed light on how TTR is involved in maintaining normal cognitive processes, its role in learning and memory, under memory deficit conditions;by which mechanisms it promotes neurite outgrowth;and how it protects the brain from Alzheimer disease (AD).

Induction of Apoptosis in Hormone-resistant Human Prostate Cancer PC3 Cells by Inactivated Sendai Virus

Objective Inactivated Sendai virus particle [hemagglutinating virus of Japan envelope （HVJ-E）] has a potential oncolytic effect due to its ability to induce apoptosis in tumor cells. However, the molecular mechanism of apoptosis induction in cancer cells mediated by HVJ-E has not been fully elucidated. This paper aims to investigate the underlying mechanism of apoptosis induction by HVJ-E in prostate cancer cells （PC3）. Methods PC3 cells were treated with HVJ-E at various MOI, and then interferon-β（IFN-β） production, and the cell viability and apoptosis were detected by ELISA, MTl--based assay and flow cytometry, respectively. Next, the roles of Jak-Stat, MAPK and Akt pathways played in HVJ-E-induced apoptosis in PC3 cells were analyzed by immunoblot assay. To further evaluate the cytotoxic effect of HVJ-E on PC3 cells, HVJ-E was intratumorally injected into prostate cancers on BALB/c-nude mice, and the tumor volume was monitored for 36 days. Results HVJ-E induced iFN-β production and activated Jak-Stat signaling pathway, which resulted in the activation of caspase-8, caspase-3, and PARP in PC3 prostate cancer cells post HVJ-E treatment. Furthermore, we observed for the first time that p38 and Jnk MAPKs in PC3 cells contributed to HVJ-E-induced apoptosis. In addition, intratumoral HVJ-E treatment displayed a direct inhibitory effect in an in vivo BALB/c nude mouse prostate cancer model. Conclusion Our findings have provided novel insights into the underlying mechanisms by which HVJ-E induces apoptosis in tumor cells.

Human menstrual blood-derived stem cells alleviate autoimmune hepatitis via JNK/MAPK signaling pathway in vivo and in vitro

Autoimmune hepatitis(AIH)is a severe globally distributed liver disease that could occur at any age.Human menstrual blood-derived stem cells(MenSCs)have shown therapeutic effect in acute lung injury and liver failure.However,their role in the curative effect of AIH remains unclear.Here,a classic AIH mouse model was constructed through intravenous injection with concanavalin A(Con A).MenSCs were intravenously injected while Con A injection in the treatment groups.The results showed that the mortality by Con A injection was significantly decreased by MenSCs treatment and liver function tests and histological analysis were also ameliorated.The results of phosphoproteomic analysis and RNA-seq revealed that MenSCs improved AIH,mainly by apoptosis and c-Jun N-terminal kinase/mitogen-activated protein signaling pathways.Apoptosis analysis demonstrated that the protein expression of cleaved caspase 3 was increased by Con A injection and reduced by MenSCs transplantation,consistent with the TUNEL staining results.An AML12 co-culture system and JNK inhibitor(SP600125)were used to verify the JNK/MAPK and apoptosis signaling pathways.These findings suggested that MenSCs could be a promising strategy for AIH.

香蕉枯萎病菌中Hog1 MAPK同源基因FoHog1敲除突变体的生物学特性

【目的】研究香蕉枯萎病菌4号生理小种中促分裂原活化蛋白激酶基因FoHog1的结构特点及其功能【方法】通过PCR和RT-PCR的方法获得了FoHog1基因序列并进行生物信息学分析,利用PEG介导的原生质体转化法得到了FoHog1基因缺失突变体,分析敲除突变体与野生型的生物学特性差异【结果】FoHog1基因编码一个含有357个氨基酸的蛋白,该蛋白在不同种镰刀菌中高度保守。通过对敲除突变体的研究发现,该基因缺失后菌丝密度下降,产孢量与菌丝干重明显降低,对乙酸钠和氯化铵的利用率下降,对温度、pH及渗透压等外源胁迫更为敏感。通过致病力实验发现,基因敲除突变体的定殖能力有所降低【结论】尖孢镰刀菌古巴专化型4号生理小种中FoHog1基因参与调控菌丝生长、分生孢子生成、乙酸钠和氯化铵代谢、渗透压胁迫反应及致病相关过程。