AUTHOR=Lv Hailong , Wang Jian , Zhang Jian , Chen Yijian , Yin Lei , Jin Dian , Gu Dayong , Zhao Huailong , Xu Yong , Wang Jin 

TITLE=Definition of CRISPR Cas12a Trans-Cleavage Units to Facilitate CRISPR Diagnostics

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.766464

DOI=10.3389/fmicb.2021.766464

ISSN=1664-302X

ABSTRACT=<p>The CRISPR diagnostic (CRISPR-Dx) technology that employs the <italic>trans</italic>-cleavage activities has shown great potential in diagnostic sensitivity, specificity, convenience, and portability, and has been recognized as the next-generation diagnostic methods. However, due to the lack of standardized definition of Cas <italic>trans</italic>-cleavage enzymatic units, it is difficult to standardize the present CRISPR-Dx systems, which have undoubtedly impeded the development of the CRISPR-Dx industry. To solve the problem, we here first systematically optimized the reaction systems for Cas12a, and then defined its <italic>trans</italic>-cleavage units (<italic>trans</italic>U), which we believe will be of great importance and interest to researchers in both molecular diagnostic industry and basic research. Moreover, a simple protocol was provided to facilitate a step-by-step measurement of the Cas12a <italic>trans</italic>U, which can also act as a reference for the definition of the <italic>trans</italic>U for other Cas proteins.</p>