UASp regulatory sequences drive expression of msps that is tagged at the C-terminal end with EYFP followed by Tag:degron(B-LID). Silent mutations have been introduced into the msps coding sequence to render it resistant to RNAi mediated by the P{TRiP.HMS01906} transgene. Subregion A of the fs(1)K10 3'UTR (this region contains the dynein-dependent transport/localization sequence (TLS) that enriches mRNA in the oocyte) is present downstream of the open reading frame.