Identification of a novel nuclear localization signal and speckle-targeting sequence of tuftelin-interacting protein 11, a splicing factor involved in spliceosome disassembly

• Published in: Biochemical and biophysical research communications Vol. 390; no. 3; pp. 1044 - 1050
• Main Authors: Tannukit, Sissada, Crabb, Tara L., Hertel, Klemens J., Wen, Xin, Jans, David A., Paine, Michael L.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 18-12-2009
• Subjects: 60 APPLIED LIFE SCIENCES; Amino Acid Sequence; AMINO ACIDS; Animals; Cell Line; CELL NUCLEI; Cell Nucleus - metabolism; G-patch; Humans; Lariat-intron; MICE; Molecular Sequence Data; Nuclear localization signal; Nuclear Localization Signals - genetics; Nuclear Localization Signals - metabolism; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Protein Structure, Tertiary; PROTEINS; RNA Helicases - genetics; RNA Helicases - metabolism; RNA processing; RNA Splicing; Spliceosomes - metabolism; SPLICING; Vesicular Transport Proteins - genetics; Vesicular Transport Proteins - metabolism; Nuclear localization signal; Lariat-intron; RNA processing; G-patch
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2009.10.111

Tuftelin-interacting protein 11 (TFIP11) is a protein component of the spliceosome complex that promotes the release of the lariat-intron during late-stage splicing through a direct recruitment and interaction with DHX15/PRP43. Expression of TFIP11 is essential for cell and organismal survival. TFIP11 contains a G-patch domain, a signature motif of RNA-processing proteins that is responsible for TFIP11–DHX15 interactions. No other functional domains within TFIP11 have been described. TFIP11 is localized to distinct speckled regions within the cell nucleus, although excluded from the nucleolus. In this study sequential C-terminal deletions and mutational analyses have identified two novel protein elements in mouse TFIP11. The first domain covers amino acids 701–706 (VKDKFN) and is an atypical nuclear localization signal (NLS). The second domain is contained within amino acids 711–735 and defines TFIP11’s distinct speckled nuclear localization. The identification of a novel TFIP11 nuclear speckle-targeting sequence (TFIP11-STS) suggests that this domain directly interacts with additional spliceosomal components. These data help define the mechanism of nuclear/nuclear speckle localization of the splicing factor TFIP11, with implications for it’s function.