nuclear RNA export factor 1; Tip-associated protein; Tip-associating protein; mRNA export factor TAP (NXF1, TAP)

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Function

nuclear export of mRNA with retroviral constitutive transport elements
export of mRNA from the nucleus to the cytoplasm
heterodimer with NXT1
- interacts via NTF2 domain
  - the NXF1-NXT1 heterodimer is involved in the export of HSP70 mRNA in conjunction with ALYREF/THOC4 & THOC5
  - formation of NXF1/NXT1 heterodimers is required for NXF1-mediated nuclear mRNA export
interacts with NXT2, E1B-AP5, RAE1, THOC4, nucleoporins
component of exon junction complex
interacts with FYTTD1/UIF, EIF4A3, NUPL2 & THOC5
interacts with: Saimiriine herpesvirus 2 TIP protein, NUPL2

minimal CTE binding domain consists of an RNP-type RNA binding domain (RBD) & leucine-rich repeats
the nucleoporin binding domain consists of a NTF2 domain & a TAP-C domain (UBA-like domain)
2 nucleoporin-FG-repeats binding sites (one in the NTF2 & the other in the TAP-C domain) which contribute to nucleoporin association & act synergistically to export cellular mRNAs
the NTF2 domain is functional only in the presence of NXT1 & is essential for the export of mRNA from the nucleus
the TAP-C domain mediates direct interactions with nucleoporin-FG-repeats & is necessary & sufficient for localization of NXF1 to the nuclear rim
the conserved loop 594-NWD-596 of the TAP-C domain has a critical role in the interaction with nucleoporins
the leucine-rich repeats are essential for the export of mRNA from the nucleus
the RNA-binding domain is a non-canonical RNP-type domain
belongs to the NXF family
contains 4 LRR repeats (leucine-rich repeats)
contains 1 NTF2 domain
contains 1 RRM domain (RNA recognition motif)
contains 1 TAP-C domain

nuclear, nucleoplasm & nuclear speckle
localized predominantly in the nucleoplasm & at both the nucleoplasmic & cytoplasmic faces of the nuclear pore complex
cytoplasm
- travels to the cytoplasm as part of the exon junction complex bound to mRNA
shuttles between nucleus & cytoplasm