Research progress and applications of gene editing technology CRISPR/Cas in zebrafish / 生物工程学报

Clustered regularly interspaced short palindromic repeats (CRISPR) are acquired immune system in bacteria and archaea. This system is used in site-directed gene editing. Recently, scientists discovered new CRISPR-associated (Cas) proteins, in which Cas12a-mediated gene editing can significantly reduce the off-target rate. In this article, we review CRISPR/Cas system's discovery of history, composition, classification, and working principle. The latest research progress of the CRISPR/Cas system, and its application in zebrafish are introduced.

Effect of miR-483-3p on DLC1 Expression in Colorectal Cancer / 胃肠病学

Background:Suppression of tumor suppressor genes plays a key role in the pathogenesis and progress of tumors. Some microRNAs may contribute to tumorigenesis by regulating tumor suppressor genes. Aims:To investigate the targeted regulatory effect of miR-483-3p on deleted in liver cancer 1(DLC1)gene in colorectal cancer. Methods:Sixteen patients with colorectal cancer admitted from October 2012 to April 2013 at Nanjing Drum Tower Hospital were enrolled. Expression of DLC1 in cancerous and adjacent noncancerous tissues was determined by Western blotting,and expression of miR-483-3p was determined by qRT-PCR. Dual luciferase reporter gene plasmid containing the 3’untranslated region(3’UTR)of DLC1 was constructed to validate the regulation of DLC1 by miR-483-3p in human colon cancer cell line HCT116. MiR-483-3p mimic was transfected into HEK293T cells and expression of DLC1 was determined by Western blotting;MiR-483-3p mimic was transfected into HCT116 cells and cell proliferation was measured by CCK-8 assay. Results:Expression of DLC1 was significantly lower in cancerous tissue than in noncancerous tissue,while expression of miR-483-3p was significantly higher in cancerous tissue than in noncancerous tissue(P<0. 05). MiR-483-3p mimic reduced the expression of DLC1 through directly binding to the 3’UTR of DLC1. Transfection of miR-483-3p mimic enhanced the proliferation of HCT116 cells significantly(P<0. 05). Conclusions:DLC1 is a target gene of miR-483-3p. MiR-483-3p might promote the development of colorectal cancer by down-regulating DLC1 expression at post-transcriptional level.