应用CRISPR/Cas9系统构建Rev-erbβ基因敲除的HEK293细胞系

目的利用成簇的、规律间隔的短回文重复序列/Cas9核酸酶(CRISPR/Cas9)基因组编辑技术,构建Rev-erbβ基因敲除的HEK293细胞系。方法通过单向导RNA(sgRNA)介导Cas9蛋白对目的基因靶位点DNA进行特异性的切割,然后经DNA同源重组单向导RNA或非同源末端连接方式进行修复,以实现对Rev-erbβ基因进行敲入、敲除修饰操作的目的。首先,针对Rev-erbβ基因设计4个sgRNA,经筛选选择活性较高的sgRNA1及sgRNA2用于构建p CMV-h Cas9-U6-Rev-erbβsgRNA1sgRNA2串联载体。然后将p CMV-h Cas9-U6-Rev-erbβsgRNA1sgRNA2和p Ad-E1/hRev-erbβdonor质粒载体共转染至HEK293细胞,通过药物筛选、克隆化及序列测序获得整合有外源供体基因片段的一条链,另一条链为片段缺失的Rev-erbβ基因完全敲除的HEK293(Rev-erbβ-/-)细胞系。最后通过用Western blot法和实时定量PCR对敲除Rev-erbβHEK293细胞系(C3-6)进行检测。结果敲除Rev-erbβ基因的HEK293细胞系中均未检测到Rev-erbβmRNA和蛋白质的表达。结论利用CRISPR/Cas9技术,成功构建了基因定点修饰和敲除的Rev-erbβ-/-HEK293细胞系,为Rev-erbβ的功能和作用机制研究提供有效工具。     

CRISPR/Cas9介导下高效敲除SQSTM1/p62基因的Hela细胞模型的建立

目的 :探讨针对p62双sgRNA向导CRISPR/Cas9基因编辑效率。方法 :采用CRISPR/Cas9基因编辑技术成功敲除p62基因,通过细胞有限稀释法和嘌呤霉素筛选,免疫印迹法验证双sgRNA和单sgRNA向导的基因编辑成功率;流式细胞仪验证p62缺失对Hela细胞凋亡的影响。结果 :免疫印迹分析得出双sgRNA导向的p62敲除效率高于单sgRNA导向的敲除,靶序列测序比对分析确认p62编码基因发生大片段缺失突变。H_2O_2处理稳定敲除的Hela细胞系显示,p62基因敲除能明显抑制Hela细胞H_2O_2诱导的早期细胞凋亡。结论 :成功建立了p62敲除的Hela细胞系,双sgRNA向导的CRISPR/Cas9基因编辑体系可能是一种更有效的编辑工具。     

利用CRISPR/Cas9系统构建4T1细胞CXCR4基因敲除稳定细胞株

目的 利用CRISPR/Cas9系统敲除4T1细胞中的CXCR4基因,构建稳定敲除CXCR4基因的4T1细胞株。 方法 根据CRISPR/Cas9靶点设计原则,在美国国立生物技术信息中心（NCBI）上找到CXCR4基因序列的外显子区域,设计两条sgRNA,用LentiCRISPRv2作为载体构建LentiCRISPRv2-sgRNA重组质粒并转化至感受态的Stbl3菌体中,挑取单克隆测序验证并扩大培养提质粒后转染至293T细胞中包装成慢病毒。 收集病毒并感染4T1细胞,通过嘌呤霉素筛选并用有限稀释法分离培养出单克隆细胞。 提取筛选出的单克隆细胞基因组DNA并对敲除位点附近的DNA片段进行PCR扩增并测序;用Real-time PCR检测细胞株CXCR4基因mRNA表达情况;用免疫印迹法检测CXCR4蛋白质的表达情况。 结果 LentiCRISPRv2-sgRNA重组质粒构建成功;经过基因组DNA片段PCR扩增测序得1株缺失27 bp的稳定敲除CXCR4基因的细胞株;细胞株CXCR4mRNA的表达量低且几乎无CXCR4蛋白质的表达。 结论 通过CRISPR/Cas9系统获得靶向敲除CXCR4基因的重组质粒,并筛选出稳定敲除CXCR4基因的细胞株。     

利用CRISPR/Cas9技术构建DOC-1R基因敲除的HEK-293稳转细胞系

目的利用CRISPR/Cas9技术敲除人胚肾(human embryonic kidney cell,HEK-293)细胞中DOC-1R,构建DOC-1R敲除的HEK-293稳转细胞系,用于进一步讨论DOC-1R的生物学功能。方法根据CRISPR/Cas9设计原则,设计向导RNA(single-guide RNA,sgRNA),构建表达载体,对sgRNA测序并转染包装HEK-293T收集上清液测定病毒滴度。前期用Cas9-puro慢病毒感染HEK-293,用已制备的DOC-1R慢病毒感染稳转Cas9的HEK-293,72 h后显微镜下观察HEK-293表达红色荧光蛋白,并用Western blot检测HEK-293中DOC-1R的表达以确定沉默效果。结果测序显示插入的sgRNA序列正确,表达载体成功构建,显微镜下观察到,90%以上HEK-293表达红色荧光蛋白,HEK-293中DOC-1R蛋白表达减少,确定了DOC-1R敲除效果最明显的序列为GCCTACCTATGCTGGCAGCA。结论利用CRISPR/Cas9技术成功构建DOC-1R基因敲除的细胞系,为进一步研究该基因的功能奠定了基础。     

应用CRISPR/Cas9系统构建敲除APE1基因的AC16心肌细胞株

目的应用CRISPR/Cas9系统构建敲除APE1基因的AC16心肌细胞株,为研究APE1在心肌细胞的功能提供研究基础。方法根据RISPR/Cas9靶向原理设计人APE1基因的导向RNA(sgRNA),构建sgRNA-LentiCRISPRV2重组质粒并转入293T细胞制备sgRNA-Cas9慢病毒;该病毒浸染AC16心肌细胞,嘌呤霉素筛选出阳性细胞并稀释至单克隆。免疫印迹法测定单克隆细胞中APE1蛋白表达。结果免疫印迹法检测的结果显示,筛选出的单克隆细胞的APE1蛋白表达完全缺失;PCR产物测序结果表明,靶向敲除APE1的心肌细胞,不存在sgRNA介导CRISPR-Cas9随机的核苷酸插入。结论应用CRISPR/Cas9系统成功构建了敲除APE1基因的AC16心肌细胞株。     

一种高效的β地中海贫血CD17（A>T）点突变293T细胞系的建立

目的 建立一种高效构建β-地中海贫血CD17（A>T）点突变基因型HEK293T细胞系的方法。 方法 利用改良的CRISPR/Cas9基因编辑技术,即无痕基因组编辑（consecutive re-Guide or re-Cas steps to erase CRISPR/Cas-blocked targets, CORRECT）,通过电转染CRISPR/Cas9质粒诱导HEK293T细胞HBB基因切割,同时以引入有CD17（A>T）点突变和同义突变碱基（G>T）的单链寡核苷酸（single-stranded oligo DNA nucleotides, ssODNs）作为同源模板进行重组,经单克隆筛选、测序验证获得β-珠蛋白基因（HBB）点突变CD17（A>T）基因型HEK293T细胞系。 结果 利用“CORRECT”技术成功获得一株β-地贫CD17（A>T）基因型点突变的HEK293T细胞系,同义突变的引入减少Cas9蛋白对靶点不准确的再编辑,提高单碱基突变效率。 结论 通过“CORRECT”技术可以高效获得点突变的293T细胞系,对单碱基突变疾病模型的细胞系及动物模型的建立具有重要意义。     

靶向猪基因组单链向导RNA快速筛选以及利用图案微阵列收获单克隆细胞的研究

规律性短重复回文序列簇(CRISPR)和CRISPR辅助蛋白9(Cas9)构成的CRISPR/Cas9基因编辑技术快速推进了基因修饰猪作为医学研究模式动物的广泛应用。而高效的靶基因单链向导RNA(sgRNA)是利用CRISPR/Cas9技术进行基因编辑成功的关键,对于猪等繁殖周期较长的大动物,则需要在实施动物实验前,在体外筛选出高效的sgRNA以避免时间和资源成本浪费。另外,如何高效获得阳性基因编辑单克隆细胞是目前尚待解决的难题。本研究建立了靶向猪基因组的sgRNA快速筛选方法,利用荧光载体富集基因编辑细胞,同时探索利用图案微阵列培养技术快速获得单克隆细胞的方法,在此基础上高效获得延胡索酰乙酰乙酸酶(Fah)基因编辑细胞,为后续生产作为人类肝细胞生物反应器的Fah基因敲除猪奠定基础。     

核仁磷酸蛋白基因NPM1敲除人宫颈癌细胞株的构建及功能

目的通过CRISPR/Cas9系统定向敲除人类宫颈癌细胞(HELA)的核仁磷酸蛋白1基因(nucleophosmin1, NPM1),探讨敲除对HELA细胞生物学行为的影响。方法利用http://crispr.mit.edu sgRNA在线设计工具设计sgRNA,通过T7E1系统筛选合适的sgRNA,将设计好的质粒通过转染的方式转入HELA细胞株,通过博来霉素(zeocin)抗生素进行筛选,通过Western blot,PCR,基因测序等手段确认敲除细胞系的建立,通过免疫荧光的方式观察敲除细胞株。结果 T7E1酶切PCR退火产物之后琼脂糖凝胶结果表明,CRISPR/Cas9系统对HELA细胞基因组进行了切割,并在同源重组时发生了碱基错配;Western blot结果说明基因敲除后NPM1蛋白表达消失;基因测序的结果表明敲除细胞系建立的成功;免疫荧光的结果表明该细胞系出现异常核仁现象。结论 NPM1敲除后细胞核仁异常,可能影响细胞正常生命进程。     

CRISPR质粒和同源重组模板的共转染可降低CRISPR/Cas9系统的基因编辑效率

目的探讨CRISPR质粒和同源重组模板的共转染对CRISPR/Cas9系统的基因编辑效率的影响以及可行的解决办法。方法用T7E1内切酶实验和RT-qPCR检测只转染CRISPR质粒组和质粒和模板共转染组细胞内Cas9的切割效率,Cas9 RNA和DNA水平的差异;RT-qPCR检测降低共转染的模板DNA的数量时,细胞内Cas9 DNA和RNA水平的变化;RT-qPCR和T7E1内切酶实验检测先转染CRISPR质粒后转染同源重组模板时,细胞内Cas9 DNA和RNA水平以及切割效率的变化。结果与只转染CRISPR质粒组相比,CRISPR质粒和同源重组模板的共转染显著降低了CRISPR质粒的转染效率(P0.001)和Cas9的切割效率(P0.001)。而先转染质粒后转染同源重组模板组和只转染质粒组在CRISPR质粒的转染效率和Cas9的切割效率差别无统计学意义。结论 CRISPR质粒和同源重组模板的共转染降低了CRISPR/Cas9系统的基因编辑效率,而先转染质粒后转染同源重组模板可以解决这一问题。     

规律间隔成簇短回文重复序列/相关蛋白9靶向Rho GDIα基因敲除质粒的构建及其对小鼠肝癌细胞系Hepa 1-6迁移的影响

目的 利用规律间隔成簇短回文重复序列/相关蛋白9(CRISPR/Cas9)技术构建Rho鸟苷酸解离抑制因子α(GDIα)的基因敲除载体,并探讨干扰Rho GDIα后对小鼠肝癌细胞Hepa 1-6迁移的影响.方法 根据CRISPR/Cas9靶点设计原则,设计Rho GDIα的向导RNA(sgRNA)序列,并与PX458载...     

Schizophrenia in a North Swedish geographical isolate, 1900–1977. Epidemiology, genetics and biochemistry

Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc² (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.     

The dominant diseases of modernized societies as omega-3 essential fatty acid deficiency syndrome: Substrate beriberi

About 1900, modern food selection and processing caused widespread $\text{epidemics}$ of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a $\text{panh}$ypovitaminosis B, i.e., a mixture of $\text{substrate}$ beriberi and $\text{substrate}$ pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse $\text{endemic}$ disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for $\text{primates}$. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.     

The universal muscular chain reaction,muscle spasm,Torsions, ruptures and extravasations. Chameleons of pathology and some manifestations of simple muscular disorders

Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.     

'Very sore nights and days': the child's experience of illness in early modern England, c.1580-1720

Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.     

Guidelines for the Validation and Use of Immunoassays for Determination of Introduced Proteins in Biotechnology Enhanced Crops and Derived Food Ingredients

Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.     

Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)

The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.     

Hypo- und Hypermagnesämie aus kardiologischer Sicht

Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.     

HLA in North Colombia Chimila Amerindians

HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.     

The case for allele‐specific recognition by the TCR

There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.