来自Type Ⅴ-F家族的CRISPR/Cas12f蛋白报道仅为Cas9蛋白分子的1/4到1/3大小，在病毒载体的递送上具有重要优势。然而，CRISPR/Cas12f系统介导植物基因编辑的报道较少，编辑活性相对较低，限制了该系统在植物上的进一步应用。本研究分别在体外酶切、酵母以及玉米原生质体瞬时表达3个体系中比较了OsCas12f、SpCas12f及UnCas12f的编辑活性。结果表明，基于Cas12f/sgRNA的体外酶切，OsCas12f与SpCas12f蛋白的编辑活性相当，未检测到UnCas12f对底物酶切活性；在酵母突变eGFP的恢复表达试验中，OsCas12f在2个测试位点对eGFP蛋白的表达恢复效率达到95%以上，效率与Cas12i.3相当；SpCas12f介导的2位点eGFP蛋白表达恢复效率分别是1.63%与3.20%，效果次之；UnCas12f蛋白几乎无编辑活性；玉米原生质体瞬时表达比较OsCas12f和SpCas12f介导的玉米内源位点的编辑效率，发现OsCas12f对2个位点的编辑效率分别为2.72%和1.97%，而SpCas12f仅能介导其中1个位点的定点编辑，编辑效率为1.09%。Cas12f蛋白在靶位点处引入的突变类型以碱基的缺失为主，缺失碱基长度在?9~ ?17 bp之间。综上，OsCas12f可以作为植物微型基因编辑器及衍生技术开发的底盘工具酶。

CRISPR/Cas12f proteins belonging to the Type V-F family are reported to be only 1/4 to 1/3 the size of Cas9 protein molecules, providing a significant advantage in viral vector delivery. However, the CRISPR/Cas12f system for gene editing in plants has been reported to have lower editing activity, limiting its broader application in plant research. In this study, we compared the editing activities of OsCas12f, SpCas12f, and UnCas12f in three different systems: in vitro digestion, yeast, and transient expression in maize protoplasts. The results showed that the editing activities of OsCas12f and SpCas12f proteins were comparable in terms of in vitro digestion of Cas12f/sgRNA complexes, while no substrate digestion activity was detected for UnCas12f. In the yeast mutant eGFP expression restoration assay, OsCas12f exhibited an editing efficiency of over 95% at the two tested loci, which was comparable to Cas12i.3. On the other hand, SpCas12f achieved editing efficiencies of 1.63% and 3.20% at the two sites, respectively, representing the next highest effect. However, UnCas12f showed minimal editing activity. Furthermore, by transiently expressing maize protoplasts, we compared the editing efficiencies of OsCas12f and SpCas12f at endogenous maize loci. It was found that OsCas12f successfully mediated targeted editing at two loci with editing efficiencies of 2.72% and 1.97%, respectively, while SpCas12f only mediated targeted editing at one locus with an editing efficiency of 1.09%. Deletion of bases was the predominant type of mutation introduced by Cas12f proteins at the target loci, with deletion lengths ranging from ?9 to ?17 base pairs. These comprehensive results indicate that OsCas12f can serve as a versatile tool for developing plant microgene editors and related technologies.