6.5kb genomic fragment containing osk expressed under the control of its own regulatory sequences. Six copies of the Tag:MS2 stem loop have been inserted into the 3'UTR, immediately after the stop codon. A translatable cassette containing twelve copies of the Tag:PP7 stem loop have been inserted, in frame, into the coding region. This construct is designed to be used in the 'TRICK' (translating RNA imaging by coat protein knockoff) system, which allows untranslated mRNAs to be distinguished from ones that have undergone a round of translation. Prior to translation, the Tag:MS2 and Tag:PP7 RNA stem loops can be bound by distinct fluorescent proteins fused to the Tag:MCP and Tag:PCP proteins respectively. During the first round of translation, the fluorescent protein containing Tag:PCP is knocked off the mRNA by the ribosome, since the Tag:PP7 stem loop is located within the coding region. The resulting change in fluorescent readout can be used to monitor translation.