CRISPR-Cas系统新的应用:SHERLOCK检测技术
华裔科学家张锋利用CRISPR-Cas新系统,研发出了新的快速,便宜,高灵敏度的诊断工具,可以用于检测诸如寨卡病毒感染和登革热感染等的疾病,这一进展也有助于便捷检测和诊断许多其它的病原体,该结果发表在著名杂志科学(Science)上。不同于Cas9,新的Cas蛋白是Cas13a,具有在剪切掉目标RNA后还能保持活性,可以“插手”剪切其他非目标RNA的特点。运用Cas13a的“连带剪切”特性,再添加一种特定RNA荧光标记物,并使用特殊扩增技术,依靠体温扩增检测样本中的RNA,就形成了一个准确检测到单个核酸分子的检测系统。
该系统命名为“神探夏洛克(SHERLOCK,Specific High Sensitivity Enzymatic Reporter UnLOCKing)”。可以用于检测血清、尿液和唾液中低浓度的寨卡病毒,而且可以用于检测病毒载量,区分不同的菌株,甚至能分辨独有不同耐药突变的肺炎菌株和不同的癌症突变。
又是一篇科学(Science)文章,祝贺华裔大神在“神”的道路上继续高速前进。
原文摘要:
Nucleic acid detection with CRISPR-Cas13a/C2c2
Abstract:Rapid, inexpensive, and sensitive nucleic acid detection may aid point-of-care pathogen detection, genotyping, and disease monitoring. The RNA-guided, RNA-targeting CRISPR effector Cas13a (previously known as C2c2) exhibits a "collateral effect" of promiscuous RNAse activity upon target recognition. We combine the collateral effect of Cas13a with isothermal amplification to establish a CRISPR-based diagnostic (CRISPR-Dx), providing rapid DNA or RNA detection with attomolar sensitivity and single-base mismatch specificity. We use this Cas13a-based molecular detection platform, termed SHERLOCK (Specific High Sensitivity Enzymatic Reporter UnLOCKing), to detect specific strains of Zika and Dengue virus, distinguish pathogenic bacteria, genotype human DNA, and identify cell-free tumor DNA mutations. Furthermore, SHERLOCK reaction reagents can be lyophilized for cold-chain independence and long-term storage, and readily reconstituted on paper for field applications.