CRISPR-mediated
[www.isaaa.org] genome
editing with the Streptococcus pyogenes Cas9 enzyme is revolutionizing life
science research by providing new tools for
[www.isaaa.org] genetic
modification due to its specific targeting in the genome of hosts. While
plant biotechnologists have used the Cas9-based system since 2013, there are
still some limitations to its use in plants.

Solutions could come from new variants of genome editing enzymes that were
recently discovered and comparable to the Cas9 in terms of precision.
However, most of them are less well known in the plant science community.

These include systems with improved RNase activity such as C2c2 from
Leptotrichia shahii and Cas9 from Francisella novicida. Other systems are
relatively smaller, allowing for better delivery to host cells. These are
the Cas9 enzymes from Staphylococcus aureus, Streptococcus thermophiles and
Neiserria meningitides, as well as the Cpf1 enzyme from F. novicida,
Acidaminococcus sp.and Lachnospiraceae bacterium. Other Cas9 variants from
S. pyogenes are also considered due to their increased specificity.

The team of Jana Murovec from the University of Ljubljana in Slovenia
reviewed these new enzyme systems for their use for genome editing,
transcriptional regulation and cellular imaging. The team also discussed the
possibilities they offer in
<[www.isaaa.org]
.asp> plant biotechnology.

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