RT Journal Article
SR Electronic
T1 Polycomb response elements reduce leaky expression of Cas9 under temperature-inducible <em>Hsp70Bb</em> promoter in <em>Drosophila melanogaster</em>
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2022.08.29.505746
DO 10.1101/2022.08.29.505746
A1 Natalie Warsinger-Pepe
A1 Carly Chang
A1 Connor R. Desroberts
A1 Omar S. Akbari
YR 2022
UL http://biorxiv.org/content/early/2022/08/29/2022.08.29.505746.abstract
AB Heat shock inducible expression of genes through the use of heat inducible promoters is commonly used in research despite leaky expression of downstream genes of interest without targeted induction (i.e. heat shock). The development of non-leaky inducible expression systems are of broad interest for both basic and applied studies, to precisely control gene expression. Here we characterize the use of Polycomb response elements and the inducible Heat shock protein 70Bb promoter, previously described as a non-leaky inducible system, to regulate Cas9 endonuclease levels and function in Drosophila melanogaster after varying both heat shock durations and rearing temperatures. We show that Polycomb response elements can significantly reduce expression of Cas9 under Heat shock protein 70Bb promoter control using a range of conditions, corroborating previously published results. We further demonstrate that this low transcript level of heat-induced Cas9 is sufficient to induce mutant mosaic phenotypes. Incomplete suppression of an inducible Cas9 system by Polycomb response elements with no heat shock suggests that further regulatory elements are required to precisely control Cas9 expression and abundance.Competing Interest StatementO.S.A is a founder of Agragene, Inc. and Synvect, Inc. with equity interest. The terms of this arrangement have been reviewed and approved by the University of California, San Diego in accordance with its conflict of interest policies. All other authors declare no competing interests.