title: The RNA export factor, Nxt1, is required for tissue specific transcriptional regulation.
abstract: The highly conserved, Nxf/Nxt (TAP/p15) RNA nuclear export pathway is important for export of most mRNAs from the nucleus, by interacting with mRNAs and promoting their passage through nuclear pores. Nxt1 is essential for viability; using a partial loss of function allele, we reveal a role for this gene in tissue specific transcription. We show that many Drosophila melanogaster testis-specific mRNAs require Nxt1 for their accumulation. The transcripts that require Nxt1 also depend on a testis-specific transcription complex, tMAC. We show that loss of Nxt1 leads to reduced transcription of tMAC targets. A reporter transcript from a tMAC-dependent promoter is under-expressed in Nxt1 mutants, however the same transcript accumulates in mutants if driven by a tMAC-independent promoter. Thus, in Drosophila primary spermatocytes, the transcription factor used to activate expression of a transcript, rather than the RNA sequence itself or the core transcription machinery, determines whether this expression requires Nxt1. We additionally find that transcripts from intron-less genes are more sensitive to loss of Nxt1 function than those from intron-containing genes and propose a mechanism in which transcript processing feeds back to increase activity of a tissue specific transcription complex.
authors.affiliation: School of Biosciences, Cardiff University, Cardiff, United Kingdom.
authors.forename: Simona
authors.initials: S
authors.lastname: Caporilli
authors.forename: Yachuan
authors.initials: Y
authors.lastname: Yu
authors.forename: Jianqiao
authors.initials: J
authors.lastname: Jiang
authors.forename: Helen
authors.initials: H
authors.lastname: White-Cooper
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000235:genetics; D000818:Animals; D002470:Cell Survival / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics*; D004331:Drosophila melanogaster / Q000235:genetics*; D007438:Introns / Q000235:genetics; D008297:Male; D022022:Nuclear Pore / Q000235:genetics; D029543:Nucleocytoplasmic Transport Proteins / Q000235:genetics*; D009928:Organ Specificity / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D013090:Spermatocytes / Q000166:cytology / Q000254:growth & development; D013737:Testis / Q000254:growth & development / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D029721:Drosophila Proteins; D029543:Nucleocytoplasmic Transport Proteins; C498545:Nxt1 protein, Drosophila; D012333:RNA, Messenger