Functional analysis of caspase cleavable proteoforms of the Drosophila GSK-3 gene shaggy.

A comparison of the embryonic transcriptome of wild type embryos (sggisoD-DS-SFS ) with embryos harbouring mutated DEVD caspase recognition sites ( sggisoD-cI-DS-SFS ) in a major shaggy isoforms class to examine the role of caspase cleavage in sgg function. The unique N-terminal exon undegoing caspase cleavage is tagged with DsRED at its N-terminus and StrepII-Flag-StrepII upstream of caspase cleavage sites for the wild type and caspase insensitive variant versions. Overall design: Drosophila lines were engineered using CRISPR-Cas9 to carry N-terminal DsRed and internal StrepII-Flag-StrepII tags; one line is otherwise wild type, sgg[isoD-DS-SFS] the other is mutated for 2 consensus caspase recognition sites sgg[isoD-CI-DS-SFS]. RNA from 3 independent stage matched embryo collections for each line were processed for RNA-seq.