“…The PB transposon allows a large cargo capacity for exogenous genes (Chapeau et al, 2017) and shows complete reversibility of genomic modifications without footprint (Woodard, Wilson, & Matthew, 2015). Traditional PB transposon systems are composed of transposon vectors (donor plasmids) and transposase expression vectors (helper plasmids), the possibility of active PBase gene insertions into the host genome exists and has rarely been addressed (Chang, Pan, Landrette, Ding, & Xu, 2019; Jia et al, 2021). PB transposase mRNA (PBase mRNA) instead of helper plasmids was regarded as an ideal method to avoid this risk (Sato, Inada, Saitoh, Watanabe, & Nakamura, 2020; Solenne et al, 2013).…”