USP22基因克隆及其融合蛋白真核表达载体的构建

目的 克隆人类泛素水解酶22(ubiquitin-specific processing enzyme 22,USP22)基因,构建与绿色荧光蛋白融合表达的真核载体.方法 利用RT-PCR技术以HeLa细胞总RNA为模板分别扩增USP22基因cDNA序列两片段,依次插入真核表达载体pEGFP-N1;重组质粒转染HEK293T细胞,观察融合蛋白表达及绿色荧光的分布.结果 测序结果显示USP22序列与GenBank收录数据一致,酶切显示重组质粒pEGFP-USP22构建无误,质粒转染后有80 %左右HEK293T细胞表达绿色荧光,且在胞质与胞核中广泛分布.结论 成功克隆USP22基因并构建与GFP融合表达的真核载体,为进一步深入研究USP22基因的生物学功能奠定了基础.     

HIV结构蛋白p24与三基序蛋白22胞内定位及出胞研究

比较p24-DsRed1、p24-DsRed2、p24-DsRed-Monomer三种荧光蛋白的表达强弱,观察p24-DsRed1与TRIM22-EGFP结合物在细胞中的分布特点。构建pDsRed1-N1-p24及pDsRed2-N1-p24真核表达载体,转染HEK293T细胞,经荧光显微镜比较三种p24-DsRed荧光偶联蛋白的表达强度。选择荧光强度最强的pDsRed1-N1-p24与pEGFP-N3-TRIM22共转染HEK293T细胞,荧光显微镜观察两者结合物在细胞中的分布特点。结果显示,经荧光显微镜检测,转染48h后红色荧光蛋白强度由大到小依次为p24-DsRed1、p24-DsRed2、p24-DsRedm。在HEK293T细胞中共转染p24-DsRed1和TRIM22-EGFP,发现两者存在共定位关系,有意思的是两者的结合体能以出胞形式脱离细胞。结果表明,p24-DsRed1荧光蛋白强度显著高于p24-DsRed2和p24-DsRedm,TRIM22-p24结合物能以出芽形式脱离细胞。     

半胱氨酸和甘氨酸富集蛋白1的基因克隆真核表达及细胞定位

目的 构建带FLAG标签的半胱氨酸和甘氨酸富集蛋白1(CRP1)的真核表达载体,明确该融合蛋白在人胚肾293T细胞、肝癌HepG2细胞和乳腺癌ZR75-1细胞中的表达及定位情况.方法 采用PCR技术从乳腺cDNA文库中扩增出人CRP1基因,并将其插入到pCMV-Tag2B表达载体中;将重组质粒转染人胚肾293T细胞、肝癌HepG2细胞、乳腺癌ZR75-1细胞,Western blot法检测转染细胞的表达情况;荧光显微镜观察pCMV-FLAG-CRP1在人胚肾293T细胞、肝癌HepG2细胞、乳腺癌ZR75-1细胞中的定位.结果 双酶切和测序鉴定表明,pCMV-FLAG-CRP1真核表达质粒构建成功;Western blot法检测pCMV-FLAG-CRP1转染293T细胞、肝癌HepG2细胞、乳腺癌ZR75-1细胞后成功表达;荧光显微镜下观察,在293T、HepG2、ZR75-1细胞中,CRP1在细胞质和细胞核中均有分布,且胞质信号强于胞核.结论成功构建pCMV-FLAG-CRP1真核表达载体,CRP1可在不同细胞中的胞质和胞核表达.     

硫氧还蛋白和氧化/还原因子的融合荧光蛋白载体的构建及在293T细胞中的分布

目的构建硫氧还蛋白和氧化/还原因子的融合荧光蛋白真核表达载体,并在293T细胞中得到表达和定位。方法以RT-PCR方法从PC12细胞中克隆氧化/还原因子(APE/ref-1)的cDNA,然后亚克隆构建APE/ref-1-GFP融合真核表达载体。以PCR方法将质粒pQE30-TRX上的硫氧还蛋白cDNA亚克隆到pDsred1-1质粒上,然后将硫氧还蛋白-DsRed融合基因序列亚克隆到pCMV5质粒上,构建硫氧还蛋白-DsRed融合真核表达载体.通过磷酸钙转染293T细胞,以荧光显微镜分析融合蛋白的表达及其亚细胞定位。结果成功构建了硫氧还蛋白-DsRed和APE/ref-1-GFP融合表达载体,并在293T细胞中得到表达,APE/ref-1-GFP融合蛋白定位在293T细胞核内;硫氧还蛋白-DsRed融合蛋白定位在293T细胞质和细胞核内。结论为进一步研究硫氧还蛋白和APE/ref-1之间的动态相互作用奠定基础。     

人黑色素浓集激素受体2基因shRNA真核表达载体体外转染

目的构建针对人黑色素浓集激素受体2(MCHR2)的短发夹RNA(shRNA)真核表达载体,并观察其转染效率。方法根据MCHR2基因序列,设计并合成特异性的小干扰片段,将其定向克隆到真核表达载体pGenesil-1中,酶切和测序后,用脂质体转染到HEK293细胞中,用荧光显微镜和流式细胞仪观察荧光表达,鉴定转染效率。结果与结论成功构建4条表达shRNA的质粒及其阴性对照质粒,并成功转染到HEK293细胞系中,转染效率达50%以上。     

人DRR1真核表达载体和稳定转染HEK293细胞株的建立及鉴定

目的:构建人DRR1基因的真核表达载体,通过转染HEK293细胞建立稳定的DRR1表达细胞株.方法:通过改造质粒pIRES,在其MCS1和MCS2中分别引入串联亲和纯化标签和绿色荧光蛋白基因,形成一个新的表达质粒pFSIG.将PCR扩增的DRRl1基因插入pFSIG中进行酶切和测序验证.用重组质粒pFSIG-DRR1转染HEK293细胞,通过G418和绿色荧光检测筛选DRR1稳定表达细胞株.通过Westernblot鉴定FS-DRR1蛋白的表达.结果:酶切、PCR和测序证实成功构建了pFSIG-DRR1表达质粒;建立了稳定转染的HEK293细胞系,Western blot检测证明重组DRR1在该细胞系中成功表达.结论:融合有串联亲和纯化标签的DRR1真核表达载体的构建和稳定表达细胞HEK293株的建立为在生理条件下研究DRR1的相互作用蛋白奠定了基础.     

人TRAF3IP3基因的克隆及真核表达

目的 构建人肿瘤坏死因子受体相关因子3相互作用蛋白3(TRAF3IP3)基因真核表达载体,并进行表达检测及鉴定.方法 RT-PCR扩增获得TRAF3IP3开放读码框区基因,双酶切连入真核表达载体pIRES2-EGFP,双酶切和测序鉴定阳性克隆;重组质粒磷酸钙法转染HEK293细胞,荧光显微镜观察绿色荧光蛋白的表达,实时定量PCR和Western blot法鉴定TRAF3IP3基因的表达情况.结果 经限制性内切酶酶切鉴定和测序证实,成功构建了TRAF3IP3真核表达质粒,荧光显微镜观察可见转染了重组质粒的HEK293细胞有绿色荧光蛋白的表达,实时定量PCR和Western blot结果证实TRAF3IP3蛋白高水平表达.结论 成功构建了pIRES-EGFP-TRAF3IP3真核表达质粒,为TRAF3IP3基因功能的研究奠定了基础.     

ctB和ure I双基因融合表达及其免疫特性分析

目的构建霍乱毒素B亚单位(CtB)和幽门螺杆菌尿素膜通道蛋白(UreI)融合的原核表达质粒pET32a( )ctB/ureI,并初步研究融合蛋白CtB/UreI的表达特性和免疫特性。方法PCR从pUC18ctB中克隆ctB基因,定向在pET32a( )/ureI的ureI基因5′端插入ctB基因,构建ctB和ureI双基因原核表达质粒pET32a( )ctB/ureI,转该质粒于E.coliBL-21(DE3),经酶切和序列分析鉴定工程菌。IPTG诱导表达,HP-His亲和层析纯化,SDS-PAGE和Gel-ProAnalizer4分析,重组蛋白免疫BALB/c小鼠。用Westernblot和ELISA分析重组蛋白的免疫特性。结果工程菌含完整的ctB和ureI基因,与相对应基因的序列同源性分别为100%。在22℃,1mmol/LIPTG诱导4h后,重组蛋白的表达占菌体总蛋白12%,亲和层析纯化后蛋白纯度为94.3%。Westernblot表明重组蛋白分别能与相应的抗体反应,该蛋白免疫小鼠后能产生相应的IgG抗体。结论成功构建了能表达CtB/UreI蛋白的大肠杆菌表达菌株。对融合蛋白表达和纯化后,初步证明了该重组蛋白有CtB和UreI的双特异反应原性和免疫原性,为研究新型幽门螺杆菌疫苗奠定了坚实的基础。     

甲型流感病毒M2e与CtB基因融合表达及其免疫特性初步研究

目的: 构建真核表达重组质粒pcDNA3.1a( )-M2e/CtB, 并初步研究其在NIH3T3细胞中的表达特性及免疫特性.方法: 重叠PCR法扩增甲型流感病毒M2e基因和霍乱毒素CtB基因, 将扩增得到的融合基因片段M2e-CtB定向克隆入真核表达载体pcDNA3.1a( )中, 再转化E.coli JM109.将酶切鉴定、 PCR扩增及序列鉴定正确的重组质粒命名为pcDNA3.1a( )-M2e/CtB.用KEGEN TRANS Ⅲ阳离子聚合物将重组质粒pcDNA3.1a( )-M2e/CtB转染NIH3T3细胞, 经免疫荧光、 RT-PCR产物序列分析、 Western blot检测其稳定表达产物.结果: 重组质粒pcDNA3.1a( )-M2e/CtB含完整的M2e和CtB基因, 与相对应基因的序列同源性分别为100%.重组质粒转染NIH3T3细胞后获得了有效表达, 并且稳筛株细胞裂解物和上清均能用抗霍乱毒素抗体和抗流感病毒抗体检测到Mr约18 000的蛋白条带.结论: 成功构建了真核表达重组质粒pcDNA3.1a( )-M2e/CtB, 初步证明其在体外表达的重组蛋白可分泌至胞外, 且有M2e和CTB的双特异反应原性和免疫原性, 为流感病毒核酸疫苗的进一步研究奠定了坚实基础.     

人SYNOVIOLIN基因真核表达载体的构建及表达

目的：构建携EGFP的人SYNOVIOLIN基因真核表达载体。方法：应用基因重组技术,根据人SYNOVIOLIN基因序列和表达载体pIRES2-EGFP质粒上的多克隆位点设计引物,对含有SYNOVIOLIN基因的质粒pCDNA3-syno扩增,得到约1900 bp的目的片段,进行T-A克隆。SalⅠ/BamHⅠ双酶切测序正确的重组质粒,回收SYNOVIOLIN cDNA片段,将其亚克隆于pIRES2-EGFP载体的多克隆位点内得到质粒pIRES2-EGFP-syno。脂质体法转染HEK293细胞, 用激光共聚焦显微镜和Western blot检测EGFP和SYNOVIOLIN在HEK293细胞的表达。结果：PCR,酶切及测序结果表明pIRES2-EGFP-syno真核表达载体构建成功,激光共聚焦显微镜和Western blot显示EGFP和SYNOVIOLIN蛋白在HEK293细胞中成功表达。结论：成功构建pIRES2-EGFP-syno真核表达载体并在HEK293细胞表达,为抗肌腱粘连的　SYNOVIOLIN基因治疗研究奠定基础。     

Pain and Effusion and Quadriceps Activation and Strength

Context:

Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive.

Objective:

To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction.

Design:

Crossover study.

Setting:

University research laboratory.

Patients or Other Participants:

Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers.

Intervention(s):

All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee.

Main Outcome Measure(s):

Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced.

Results:

Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05).

Conclusions:

Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high.Key Words: arthrogenic muscle inhibition, central activation failure, voluntary activation, muscles

Key Points

• Knee pain and effusion resulted in arthrogenic muscle inhibition and weakness of the quadriceps.
• The simultaneous presence of pain and effusion did not increase the magnitude of quadriceps dysfunction.
• To reduce arthrogenic muscle inhibition and improve muscle strength, clinicians should employ interventions that target removing both pain and effusion.

Quadriceps weakness is a common consequence of traumatic knee joint injury^1,2 and chronic degenerative knee joint conditions.^3,4 Arthrogenic muscle inhibition (AMI), a neurologic decline in muscle activation, results in quadriceps weakness and hinders rehabilitation by preventing gains in strength.⁵ The inability to reverse AMI and restore muscle function can lead to decreased physical abilities,⁶ biomechanical deficits,⁷ and possibly reinjury.⁵ Furthermore, researchers^8,9 have suggested that quadriceps weakness resulting from AMI may place patients at risk for developing osteoarthritis in the knee. In light of the substantial influence of quadriceps AMI on these clinically relevant outcomes, we need to improve our understanding of the factors that contribute to this neurologic decline in muscle activity so efforts to target and reverse it can be implemented and gains in strength can be achieved more easily.Joint injury and disease are accompanied by numerous sequelae (ie, pain, swelling, tissue damage, inflammation), so ascertaining which one ultimately leads to neurologic muscle dysfunction is difficult. Whereas a joint effusion can result in AMI,^10–12 the effects of pain are less understood despite many clinicians attributing AMI to pain. Using techniques that introduce knee pain without accompanying injury may provide insights into the role of pain in eliciting AMI.The degree of knee joint damage may play a role in the quantity of AMI that manifests. Hurley et al^13,14 demonstrated that quadriceps AMI, measured using an interpolated-twitch technique, was greater in patients with extensive traumatic knee injury (eg, fractured tibial plateau, ruptured medial collateral ligament, and medial meniscectomy) than patients with isolated joint trauma (ie, isolated anterior cruciate ligament [ACL] rupture). Similarly, patients with more knee joint symptoms (ie, greater number of symptoms and increased severity of symptoms) may present with greater magnitudes of quadriceps inhibition. Recently, investigators¹⁵ have suggested that patients with more pain display less quadriceps strength, supporting this tenet. Given that effusion and pain often present simultaneously with joint injuries and diseases, such as ACL injury and osteoarthritis, examining both the isolated and cumulative effects of these sequelae appears warranted to determine if they influence the magnitude of muscle inhibition.Experimental joint-effusion and pain models are safe and effective experimental methods that allow for the isolated examination of their effects on muscle function. The effusion model, whereby sterile saline is injected directly into the knee joint capsule,⁷ produces a clinically relevant magnitude of the joint effusion that may be present with traumatic injury. Effusion is thought to activate group II afferents responding to stretch or pressure,^16–18 which in turn may facilitate group Ib interneurons and result in quadriceps AMI.⁵ The pain model involves injecting hypertonic saline into the infrapatellar fat pad to produce anteromedial knee pain similar to that described in patients with patellofemoral pain syndrome.¹⁹ Pain is considered to initiate AMI through activation of group III and IV afferents that act as nocioceptors to signal damage or potential damage to joint structures.^16–18 The firing of these afferents then may lead to facilitation of group Ib interneurons, the flexion reflex, or the gamma loop, ultimately resulting in quadriceps inhibition.²⁰ Thus, these models allow us to create symptoms that are associated with knee injury and have the added benefit of providing a way to examine their effects in isolation.Therefore, the purpose of our study was to determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion would affect the magnitude of quadriceps dysfunction. We hypothesized that pain alone would result in quadriceps inhibition and that the magnitude of inhibition would be greater when effusion and pain were present simultaneously.     

即早基因c-fos与脑血管病及学习记忆

即早基因c-fos是广泛存在于原核细胞和真核细胞的高度保守基因.在正常情况下,c-fos基因参与细胞生长、分化、信息传递、学习和记忆等生理过程,而在病理情况下c-fos基因表达及调控变化与多种疾病的发生和发展有关.C-fos在中枢神经系统的某些部位可有基础水平的表达,但表达很低,当受到如脑缺血、脑出血、痫性发作、应激等刺激后,其在数十分钟内做出反应,在对外界刺激-转录耦联的信忠传递过程中起着核内第三信使的重要作用.     

Opportunities and challenges in the prevention and control of cancer and other chronic diseases: children's diet and nutrition and weight and physical activity

OBJECTIVE: The purpose of this article is to review the role of behavioral research in disease prevention and control, with a particular emphasis on lifestyle- and behavior-related cancer and chronic disease risk factors--specifically, relationships among diet and nutrition and weight and physical activity with adult cancer, and tracking developmental origins of these health-promoting and health-compromising behaviors from childhood into adulthood. METHOD: After reviewing the background of the field of cancer prevention and control and establishing plausibility for the role of child health behavior in adult cancer risk, studies selected from the pediatric published literature are reviewed. Articles were retrieved, selected, and summarized to illustrate that results from separate but related fields of study are combinable to yield insights into the prevention and control of cancer and other chronic diseases in adulthood through the conduct of nonintervention and intervention research with children in clinical, public health, and other contexts. RESULTS: As illustrated by the evidence presented in this review, there are numerous reasons (biological, psychological, and social), opportunities (school and community, health care, and family settings), and approaches (nonintervention and intervention) to understand and impact behavior change in children's diet and nutrition and weight and physical activity. CONCLUSIONS: Further development and evaluation of behavioral science intervention protocols conducted with children are necessary to understand the efficacy of these approaches and their public health impact on proximal and distal cancer, cancer-related, and chronic disease outcomes before diffusion. It is clear that more attention should be paid to early life and early developmental phases in cancer prevention.