Baptiste Rafanel
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baptisterafanel.bsky.social
Baptiste Rafanel
@baptisterafanel.bsky.social
50 followers 53 following 12 posts
Transposons, Transcription, piRNA, Drosophila
PhD Student in the Brennecke lab at IMBA
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baptisterafanel.bsky.social
7/ To test this idea, we generated a synthetic construct in which we placed antisense tirant sequence into the 3′ UTR of a UAS-GFP transgene. When expressed in follicle cells, this transgene silenced tirant expression, confirming our model.
A GFP transgene containing an antisense tirant insertion in the 3'UTR can silence tirant expression. An insertion in the sense orientation does not affect the expression of tirant.
August 14, 2025 at 5:09 PM
baptisterafanel.bsky.social
5/ Surprisingly, we found that a single antisense insertion of tirant in the 3′ UTR of a host gene, Fs(2)Ket, is sufficient to trigger piRNA production and silence tirant. piRNA production from this insertion requires host gene transcription and a chimeric mRNA-TE transcript.
An insertion of tirant in the antisense orientation in the 3'UTR of the gene Fs(2)Ket leads to the production of piRNAs. An ectopic copy of the gene Fs(2)Ket containing the tirant insertion is sufficient for the production of piRNAs and silencing of tirant. This requires the production of a chimeric transcript containing both the Fs(2)Ket and the tirant RNA.
August 14, 2025 at 5:09 PM
baptisterafanel.bsky.social
3/ We first show that tirant is exclusively expressed in somatic cells of the ovary. Here, most strains also produce tirant piRNAs from tirant insertions in flamenco, the major piRNAs cluster active in that tissue. But this is not true in all strains …
The tirant-GFP:lacZ reporter is expressed in the somatic follicle cells of the Drosophila melanogaster ovary and is silenced by piRNAs.
August 14, 2025 at 5:09 PM