Xiya Reagent:全基因组转录激活Genome-scale transcriptional activation by

Systematic interrogation of gene function requires the ability to perturb gene expression in a robust and generalizable manner. Here we describe structure-guided engineering of a CRISPR-Cas9 complex to mediate efficient transcriptional activation at endogenous genomic loci. We used these engineered Cas9 activation complexes to investigate single-guide RNA (sgRNA) targeting rules for effective transcriptional activation， to demonstrate multiplexed activation of ten genes simultaneously， and to upregulate long intergenic non-coding RNA (lincRNA) transcripts. We also synthesized a library consisting of 70，290 guides targeting all human RefSeq coding isoforms to screen for genes that， upon activation， confer resistance to a BRAF inhibitor. The top hits included genes previously shown to be able to confer resistance， and novel candidates were validated using individual sgRNA and complementary DNA overexpression. A gene signature based on the top screening hits correlated with a gene expression signature of BRAF inhibitor resistance in cell lines and patient-derived samples. These results collectively demonstrate the potential of Cas9-based activators as a powerful genetic perturbation technology.随后，研究人员建立了70，290个引导RNA的文库，来靶标人类基因组超过两万个基因。他们由此鉴定了让黑色素瘤抵抗药物PLX-4720的基因。PLX-4720对于携带BRAF突变的患者疗效比较好，残存下来的癌细胞会长成新的肿瘤，导致癌症复发。

研究人员将CRISPR元件引入大量体外培养的黑色素瘤细胞，不同细胞对应靶标不同基因的引导RNA。然后他们用PLX-4720处理这些细胞，由此鉴定帮助癌细胞生存的基因。事实上他们也的确发现了几个新的抗性基因。这样的研究可以帮助人们开发新的癌症药物，阻止肿瘤获得抗性。

下一步张锋实验室计划继续进行筛选，寻找那些激活时能校正自闭症或神经退行性疾病（比如阿尔茨海默症）的基因· 以上资料由西亚试剂：http://www.xiyashiji.com/ 提供此产品的详细信息如密度,含量,分子式,分子量等均可在西亚官网查询