**6.3 miRNA manipulation by genome editing technologies**

To access the diverse roles of miRNAs in crops, a number of investigations conducted on miRNAs [45]. Although, due to small size of miRNA, the effectiveness of the well-known approaches for functional loss and inhibiting miRNA expression are comparatively less strong. Mainly, two genome editing techniques with modified nuclease enzyme are significant for selecting appropriate genome alteration [60]. These techniques mainly depend on the production of double-stranded breaks at target sequences by TALENs (Transcription Activator-Like Effector Nucleases) and CRISPR (Clustered, Regularly Interspaced Short Palindromic Repeats) DNA modification methods [61]. CRISPR-Cas9 technology developed as an advance RNA-dependent gene and genome editing tool due to its suitability to a variety of organisms [62]. A previous study on rice demonstrated that Cas9 also guided by modified gRNA for appropriate cut and genome editing of some selected crops [63]. One more study in soybean showed that the CRISPR/Cas9 system is very effective for removing a green fluorescent tagged protein transgene and modifying nine different endogenous loci [64].

CRISPR/Cas9 genome editing technology specifically and strongly decreases the 96% expression of miRNAs [62]. This method has transformed gene editing abilities and has been useful in several model plants such as *Arabidopsis*, tobacco *etc*. and other crops plant such as rice, wheat, maize, tomato and sorghum. But noncoding RNA editing by CRISPR/Cas method in plants is still emerging [65]. Due to the effectiveness of CRISPR/Cas technology, it can be also used as an influential genome-editing tool for genetic modification and functional characterization of plant genes/miRNAs and for genome modification to improve agricultural crops [66].
