Ski-interacting protein, a bifunctional nuclear receptor coregulator that interacts with N-CoR/SMRT and p300

doi:10.1016/j.bbrc.2004.02.004

Biochemical and Biophysical Research Communications

Volume 315, Issue 4, 19 March 2004, Pages 1070-1076

https://doi.org/10.1016/j.bbrc.2004.02.004 Get rights and content

Abstract

Ski-interacting protein (SKIP), a vitamin D receptor (VDR) coactivator, also functions as a repressor in Notch signalling in association with the corepressor SMRT. Here we show that SKIP bifunctionally modulates (activates or represses) Retinoid-X receptor (RXR)- and VDR-dependent gene transcription in a cell line-specific manner, with activation in CV-1 and repression in P19 cells. The coactivator function of SKIP in these cells appeared to correlate with the relative level and ratio of expression of N-CoR and p300, with greater SKIP activation in higher p300-expressing and lower N-CoR-expressing cell-lines. C-terminal deletion of SKIP (Δ334–536 aa) was associated with strong activation in both CV-1 and P19 cells. The corepressors N-CoR and SMRT and the coregulator p300 interacted with SKIP through the same N-terminal region (1–200 aa). Overall these results suggest that transcriptional action of SKIP may depend on distinct functional domains and cell line-specific interactions with both corepressors and coactivators.

Section snippets

Materials and methods

Plasmid construction. SKIP-pSG5, mRXRβ-pExpress, SRC-1-pCR3.1, SRC-3-pCMV2, RXRE, and VDRE-promoter-luciferase reporter constructs were previously described [3], [13], [21], [22], [23]. Wild-type and deletion mutants of SKIP-pM, SKIP-pSG5, and SKIP-pCGN constructs were cloned from SKIP-pACTIIβ constructs previously described [13] by excising EcoR1/BamH1 insert from pACTIIβ plasmid and ligation into pM, pSG5, and pCGN plasmids. All mammalian two-hybrid plasmids are as previously described

SKIP as a cell line-specific transcriptional coregulator

SKIP function in RXR- and VDR-dependent transcription was initially examined in the CV-1 cell line. SKIP augmented basal activity of the control tk-luciferase and RXRE and VDRE reporters about 2–3-fold, and increased ligand-dependent RXRE and VDRE reporter activity between 4- and 10-fold in CV-1 cells (Fig. 1A). Similar results were obtained in COS-1 and HepG2 cells (data not shown).

In marked contrast, in the murine embryonal carcinoma P19 cell line, SKIP decreased ligand-dependent reporter

Discussion

Our studies confirmed SKIP to be a coactivator of VDR/RXR-dependent transcription, but also demonstrate that SKIP may act as a cell line-specific repressor. SKIP augmented ligand-dependent transcriptional activities in CV-1, and a variety of other cell-lines, including COS-1 and HepG2 (data not shown) but, in contrast, repressed reporter genes in the undifferentiated P19 embryonal carcinoma cell line. Consistent with these data SKIP was shown to interact in vitro both with coactivators (SRC-1

Acknowledgements

We especially thank Drs. A. Kouzmenko, J. Segars, and R. Dahl for critical review of the manuscript; Jonine Figueroa, Sudip Datta, and Colette Fong and Nathan Doyle for technical assistance; and the following scientific colleagues for generously providing plasmids: M. Henderson, J. Segars, B. May, B. O’Malley, L. Jameson, T. Tagami, P. Polly, T. Hienzel, and R. Eckner. G.M.L. was recipient of an Australian National Health and Medical Research Council Post-Graduate Medical Scholarship and a

References (36)

N.J. McKenna et al.
Cell
(2002)
T.A. Baudino et al.
J. Biol. Chem.
(1998)
C. Zhang et al.
J. Biol. Chem.
(2001)
J.B. Barry et al.
J. Biol. Chem.
(2003)
G.M. Leong et al.
J. Biol. Chem.
(2001)
D. Negeri et al.
Mech. Dev.
(2002)
G.M. Leong et al.
J. Biol. Chem.
(1998)
T. Tagami et al.
Biochem. Biophys. Res. Commun.
(1998)
D.G. Chen et al.
J. Biol. Chem.
(2000)
T. Huszar et al.
J. Biotech.
(2001)

R.M. Gill et al.

Exp. Cell Res.

(1998)

C.K. Glass et al.

Genes Dev.

(2000)

T.E. Spencer et al.

Nature

(1997)

B.D. Lemon et al.

Genes Dev.

(2000)

L. Alland et al.

Nature

(1997)

Y.D. Wen et al.

Proc. Natl. Acad. Sci. USA

(2000)

R. Dahl et al.

Oncogene

(1998)

S. Zhou et al.

J. Virol.

(2000)

Cited by (53)

A novel SNW/SKIP domain-containing protein, Bx42, is involved in the antibacterial responses of Macrobrachium nipponense
2020, Developmental and Comparative Immunology
Bx42, the homologue of SNW1 in mammals, is involved in pre-mRNA splicing and transcriptional regulation. However, the presence and function of Bx42 have remained poorly understood in invertebrates until now. In the current study, a novel SNW domain-containing protein (MnBx42) from Macrobrachium nipponense was identified, and its potential role in the immune response was investigated. The full-length MnBx42 was 7467 bp with an open reading frame of 1653 bp, encoding 550 amino acids. Real-time PCR analysis suggested that MnBx42 was predominantly expressed in the intestine, gills and hepatopancreas, and immunofluorescence assays indicated that it was located in the nucleus. Its expression level was significantly decreased in M. nipponense post-challenge with white spot syndrome virus (WSSV) as well as Aeromonas hydrophila and Staphylococcus aureus, implying its participation in the innate immune response. The knockdown of MnBx42 in vivo notably increased the susceptibility of the prawns to bacterial infection, markedly increased the bacterial load in the gills, and significantly attenuated the phagocytic activity of haemocytes. Dual-luciferase reporter assays illustrated that MnBx42 could activate the NF-κB pathway. Consistent with this, when MnBx42 was silenced in vivo, the expression levels of antimicrobial peptides (AMPs), including ALF2, ALF3, ALF4, ALF5, Cru1 and Cru2, and NF-κB signalling genes, including dorsal, relish, TAK1, TAB1, Ikkβ, and Ikkε, were significantly reduced. Taken together, these findings may provide new insights about Bx42 in crustaceans and pave the way for a better understanding of the crustacean innate immune system.
Role of dehydrin-FK506-binding protein complex in enhancing drought tolerance through the ABA-mediated signaling pathway
2019, Environmental and Experimental Botany
Citation Excerpt :
Similarly, Cyclophilin 18-2 (CYP18-2) genes which are a homolog of peptidylprolyl isomerase-1 interact with OsSKIP (ski interacting protein) and confers drought tolerance to transgenic Arabidopsis and rice plants (Lee et al., 2015). Available literature indicated plants ski interacting protein (SKIP) act as a transcriptional co-regulator, which are involved in ABA-mediated abiotic stress tolerance (Figueroa and Hayman, 2004; Folk et al., 2004; Leong et al., 2004). Abscisic acid (ABA) helps plants to cope up with abiotic stress either applied exogenously or by increasing endogenous content through modulation of genes in plants.
Dehydrins (DHNs) have been reported to act as chaperones to combat drought stress. While in this study, we explored a novel nuclear complex of Oryza sativa FKBP and YSK2-type dehydrin (OsDhn-Rab16D), associated with ABA signaling to impart drought stress tolerance. The transcript levels of OsDhn-Rab16D in rice seedlings were induced in response to drought, abscisic acid (ABA) and H₂O₂ exposure. Ectopic expression of OsDhn-Rab16D transgenic lines showed enhanced tolerance to both osmotic stresses caused by PEG and drought. Using the yeast two-hybrid (Y2H) assay, O. sativa FKBP (a prolyl cis-trans isomerase) was identified as an interacting partner of OsDhn-Rab16D. Fluorescence signals between OsDhn-Rab16D and OsFKBP were observed in the nucleus. The pull-down assay confirmed the physical interaction between OsDhn-Rab16D and OsFKBP. qRT-PCR of drought and ABA-responsive gene reveals the higher transcript abundance in PEG-treated transgenic lines. Moreover, under drought conditions, transgenic lines maintain membrane integrity and increase the lignification in adventitious rice roots due to the higher expression level of catalase and lignin biosynthesis enzyme, respectively, as compared with wild-type. Overall, our findings suggest that OsDhn-Rab16D and OsFKBP complex involved in ABA-responsive drought stress signaling in rice and probably act as a positive transcriptional co-regulator, in addition, to act as chaperones.
Structure and function of the vitamin D-binding proteins
2019, Principles of Bone Biology
The vitamin D-binding proteins discussed in this chapter include the major transport protein in blood, vitamin D-binding protein (DBP); the intracellular vitamin D-binding protein known as heat shock protein Hsp70; the nuclear vitamin D receptor (VDR); and two membrane receptors, VDR itself and the membrane-associated rapid response steroid-binding protein, also known as thioredoxin-like protein (GRP58), endoplasmic reticulum protein 57/60, or protein disulfide isomerase family A, member 3. This chapter describes known structural aspects of these proteins that are essential for their function as well as their roles in mediating transport of the vitamin D metabolites in blood, their cellular uptake, their movement within the cell, and their regulation of biologic processes both genomic and nongenomic.
Overexpression of SbSKIP, A Pre-mRNA splicing factor from Sorghum bicolor, enhances root growth and drought tolerance in Petunia hybrida
2018, Scientia Horticulturae
Pre-mRNA splicing factors have been shown to have important roles in understanding the response of plants to various abiotic stresses. Different splicing factors might have different roles in plant stress responses. One splicer factor, skip (Sloan-Kettering retrovirus interacting protein), has been shown to play an important role in the tolerance of plants to various abiotic stresses although its mechanism of action is unknown. SbSKIP (Sorghum bicolor skip) encodes an RNA metabolism-related protein that could improve tobacco’s drought tolerance of tobacco. There is uncertainty how SbSKIP would act in other species and it effect on potential target genes. We found that overexpression of SbSKIP in Petunia hybrida could promote the growth of lateral roots and enhance drought tolerance. After withholding water for 14 d, SbSKIP plants grew better than WT (wild-type) plants; WT plants leaves were severely wilted and died, whereas transgenic plants were turgid after 17 d of drought treatment. Water stressed transgenic plants overexpressed SbSKIP, increased leaf proline synthesis and antioxidant defense enzyme activities, and decreased the accumulation of MDA. Furthermore, SbSKIP also regulated stress-induced gene expression under drought stress. These results suggest that overexpression of SbSKIP improves the tolerance of petunia to drought stress by enhancing antioxidant defense enzymes that decrease the content of cell membrane peroxidation, and by regulating the expression of stress-induced genes and the synthesis of proline.
Enhancement of TGF-β-induced Smad3 activity by c-Abl-mediated tyrosine phosphorylation of its coactivator SKI-interacting protein (SKIP)
2017, Biochemical and Biophysical Research Communications
Citation Excerpt :
p300/CBP possess histone acetyl transferase (HAT) activity, which loosen chromatin structure by acetylation of histones, and activate transcription [27,28]. SKIP interacts with p300 to control VDR- and RXR-dependent transcription [29] and with Menin, a subunit of the MLL1 histone methyl transferase complex, to promote HIV-1 Tat transactivation [30]. Therefore, SKIP has the potential to regulate Smad3 activities in a histone acetylation- or methylation-dependent manner.
c-Abl is a non-receptor-type tyrosine kinase that plays an important role in cell proliferation, migration, apoptosis, and fibrosis. Furthermore, although c-Abl is involved in transforming growth factor-β (TGF-β) signaling, its molecular functions in TGF-β signaling are not fully understood. Here, we found that c-Abl phosphorylates SKI-interacting protein (SKIP), a nuclear cofactor of the transcription factor Smad3. The c-Abl inhibitor imatinib suppressed TGF-β-induced expression of Smad3 targets as well as SKIP/Smad3 interaction. TGF-β-stimulation induced tyrosine phosphorylation of SKIP, and this phosphorylation was suppressed by imatinib. Tyr²⁹², Tyr⁴³⁰, and Tyr⁴³³ residues in SKIP were shown to be involved in c-Abl-mediated phosphorylation. Phosphomimetic glutamic acid substitution at Tyr²⁹² in SKIP enhanced, whereas its phospho-dead phenylalanine substitution attenuated TGF-β-induced SKIP/Smad3 interaction. Moreover, the phosphomimetic mutant of SKIP augmented transcriptional activity of Smad3. Taken together, these results suggest that c-Abl phosphorylates SKIP mainly at Tyr²⁹² and promotes SKIP/Smad3 interaction for the full activation of TGF-β/Smad3 signaling.
Vitamin D: Molecular Biology and Gene Regulation
2017, Textbook of Nephro-Endocrinology
Vitamin D produced by sunlight exposure of the skin is essential for mineral metabolism and skeletal health. The high prevalence of vitamin D insufficiency in the normal population and its association with increased risk for osteoporosis, diabetes, hypertension, cardiovascular disorders, tuberculosis, autoimmune disease, and cancer have prompted a comprehensive search for the pathogenic mechanisms underlying these associations. The multitude of actions of the vitamin D system are mediated primarily by the binding of the active vitamin D hormone (1,25(OH)₂D₃ or calcitriol) to its specific cellular receptor (vitamin D receptor or VDR), which initiates the formation of complex of coregulatory factors that control the rate of gene transcription. The goal of this chapter is to present the current understanding of the molecular mechanisms underlying calcitriol/VDR induction or repression of vitamin D target genes mediating classical and nonclassical vitamin D actions, the abnormalities induced by kidney disease, as well as novel actions of the calcitriol/VDR complex in controlling mRNA translation, and VDR-independent actions of calcitriol regulating cell growth, apoptosis, and survival, with special focus on the pathophysiological significance of these processes in disease prevention in the healthy population and in ameliorating the progression of secondary hyperparathyroidism, renal lesions, renal osteodystrophy, and cardiovascular disorders in patients with kidney disease.

View all citing articles on Scopus

View full text

Ski-interacting protein, a bifunctional nuclear receptor coregulator that interacts with N-CoR/SMRT and p300

Abstract

Section snippets

Materials and methods

SKIP as a cell line-specific transcriptional coregulator

Discussion

Acknowledgements

Cell

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

Mech. Dev.

J. Biol. Chem.

Biochem. Biophys. Res. Commun.

J. Biol. Chem.

J. Biotech.

Exp. Cell Res.

Genes Dev.

Nature

Genes Dev.

Nature

Proc. Natl. Acad. Sci. USA

Oncogene

J. Virol.