The Alternative Splicing of Intersectin 1 Regulated by PTBP1 Promotes Human Glioma Progression

Overview

Journal Cell Death Dis

Specialties Cell Biology
General Medicine

Date 2022 Sep 28

PMID 36171198

Authors

Chungen Lan

Huikun Zhang

Kezhen Wang

Xiaoli Liu

Yawen Zhao

Zhifang Guo

Ning Zhang

Yongxia Zhou

Manzhi Gao

Feng Gu

Yongjie Ma

Affiliations

Soon will be listed here.

Abstract

Intersectin 1 (ITSN1) contains two isoforms: ITSN1-S and ITSN1-L, which are highly regulated by alternative splicing. Our previous results showed that the two isoforms of ITSN1 displayed opposite functions: ITSN1-S promoted glioma development, while ITSN1-L exerted an inhibitory role in glioma progression. In this study, our transcriptome analysis using a large glioma cohort indicated that the ratio of ITSN1-S/ITSN1-L was positively correlated with glioma grading and poor prognosis. We identified the RNA-binding protein polypyrimidine tract-binding protein 1 (PTBP1) as an ITSN1 pre-mRNA interaction protein through RNA pull-down assay and RNA immunoprecipitation assay. Knockdown of PTBP1 decreased the ratio of ITSN1-S/ITSN1-L. Minigene reporter assay and mutation analyses further confirmed PTBP1 targeted polypyrimidine sequences on ITSN1 exon 30 (TTGCACTTCAGTATTTT) and promoted the inclusion of ITSN1 exon 30. Subsequently, silencing PTBP1 inhibited glioma cell proliferation, migration, and invasion by down-regulating the ratio of ITSN1-S/ITSN1-L. Taken together, our study provides a novel mechanism that PTBP1 modulates the alternative splicing of ITSN1 and promotes glioma proliferation and motility by up-regulating the ratio of ITSN1-S/ITSN1-L, thereby highlighting that PTBP1 may be an attractive therapeutic target for gliomas.

Citing Articles

The emerging roles of aberrant alternative splicing in glioma.

Ben Mrid R, El Guendouzi S, Mineo M, El Fatimy R Cell Death Discov. 2025; 11(1):50.

PMID: 39915450 PMC: 11802826. DOI: 10.1038/s41420-025-02323-0.

Downregulation of Splicing Factor Curtails Expression to Promote Cellular Senescence in Lung Adenocarcinoma.

Li H, Sun X, Lv Y, Wei G, Ni T, Qin W Curr Issues Mol Biol. 2024; 46(7):7730-7744.

PMID: 39057099 PMC: 11276454. DOI: 10.3390/cimb46070458.

Alternative splicing analysis of lignocellulose-degrading enzyme genes and enzyme variants in Aspergillus niger.

Xu Y, Dong F, Wang R, Ajmal M, Liu X, Lin H Appl Microbiol Biotechnol. 2024; 108(1):302.

PMID: 38639796 PMC: 11031446. DOI: 10.1007/s00253-024-13137-y.

PTBP1 as a potential regulator of disease.

Yu Q, Wu T, Xu W, Wei J, Zhao A, Wang M Mol Cell Biochem. 2023; 479(11):2875-2894.

PMID: 38129625 DOI: 10.1007/s11010-023-04905-x.

Research Progress on the Structural and Functional Roles of hnRNPs in Muscle Development.

Li Z, Wei H, Hu D, Li X, Guo Y, Ding X Biomolecules. 2023; 13(10).

PMID: 37892116 PMC: 10604023. DOI: 10.3390/biom13101434.

References

Paradis C, Cloutier P, Shkreta L, Toutant J, Klarskov K, Chabot B . hnRNP I/PTB can antagonize the splicing repressor activity of SRp30c. RNA. 2007; 13(8):1287-300. PMC: 1924885. DOI: 10.1261/rna.403607. View

Sauliere J, Sureau A, Expert-Bezancon A, Marie J . The polypyrimidine tract binding protein (PTB) represses splicing of exon 6B from the beta-tropomyosin pre-mRNA by directly interfering with the binding of the U2AF65 subunit. Mol Cell Biol. 2006; 26(23):8755-69. PMC: 1636812. DOI: 10.1128/MCB.00893-06. View

Song H, Li Y, Lee J, Schwartz A, Bu G . Low-density lipoprotein receptor-related protein 1 promotes cancer cell migration and invasion by inducing the expression of matrix metalloproteinases 2 and 9. Cancer Res. 2009; 69(3):879-86. PMC: 2633434. DOI: 10.1158/0008-5472.CAN-08-3379. View

Guo H, Gu F, Li W, Zhang B, Niu R, Fu L . Reduction of protein kinase C zeta inhibits migration and invasion of human glioblastoma cells. J Neurochem. 2009; 109(1):203-13. DOI: 10.1111/j.1471-4159.2009.05946.x. View

Cirak S, Arechavala-Gomeza V, Guglieri M, Feng L, Torelli S, Anthony K . Exon skipping and dystrophin restoration in patients with Duchenne muscular dystrophy after systemic phosphorodiamidate morpholino oligomer treatment: an open-label, phase 2, dose-escalation study. Lancet. 2011; 378(9791):595-605. PMC: 3156980. DOI: 10.1016/S0140-6736(11)60756-3. View

Nilsen T, Graveley B . Expansion of the eukaryotic proteome by alternative splicing. Nature. 2010; 463(7280):457-63. PMC: 3443858. DOI: 10.1038/nature08909. View

Ma Y, Wang B, Li W, Liu X, Wang J, Ding T . Intersectin1-s is involved in migration and invasion of human glioma cells. J Neurosci Res. 2011; 89(7):1079-90. DOI: 10.1002/jnr.22616. View

Rajesh Y, Pal I, Banik P, Chakraborty S, Borkar S, Dey G . Insights into molecular therapy of glioma: current challenges and next generation blueprint. Acta Pharmacol Sin. 2017; 38(5):591-613. PMC: 5457688. DOI: 10.1038/aps.2016.167. View

Amir-Ahmady B, Boutz P, Markovtsov V, Phillips M, Black D . Exon repression by polypyrimidine tract binding protein. RNA. 2005; 11(5):699-716. PMC: 1370756. DOI: 10.1261/rna.2250405. View

10.

Oberstrass F, Auweter S, Erat M, Hargous Y, Henning A, Wenter P . Structure of PTB bound to RNA: specific binding and implications for splicing regulation. Science. 2005; 309(5743):2054-7. DOI: 10.1126/science.1114066. View

11.

Zheng Y, Miu Y, Yang X, Yang X, Zhu M . CCR7 Mediates TGF-β1-Induced Human Malignant Glioma Invasion, Migration, and Epithelial-Mesenchymal Transition by Activating MMP2/9 Through the Nuclear Factor KappaB Signaling Pathway. DNA Cell Biol. 2017; 36(10):853-861. DOI: 10.1089/dna.2017.3818. View

12.

Kornblihtt A, Schor I, Allo M, Dujardin G, Petrillo E, Munoz M . Alternative splicing: a pivotal step between eukaryotic transcription and translation. Nat Rev Mol Cell Biol. 2013; 14(3):153-65. DOI: 10.1038/nrm3525. View

13.

Raj B, Blencowe B . Alternative Splicing in the Mammalian Nervous System: Recent Insights into Mechanisms and Functional Roles. Neuron. 2015; 87(1):14-27. DOI: 10.1016/j.neuron.2015.05.004. View

14.

Spellman R, Smith C . Novel modes of splicing repression by PTB. Trends Biochem Sci. 2006; 31(2):73-6. DOI: 10.1016/j.tibs.2005.12.003. View

15.

Sharma S, Maris C, Allain F, Black D . U1 snRNA directly interacts with polypyrimidine tract-binding protein during splicing repression. Mol Cell. 2011; 41(5):579-88. PMC: 3931528. DOI: 10.1016/j.molcel.2011.02.012. View

16.

Lou H, Helfman D, Gagel R, Berget S . Polypyrimidine tract-binding protein positively regulates inclusion of an alternative 3'-terminal exon. Mol Cell Biol. 1998; 19(1):78-85. PMC: 83867. DOI: 10.1128/MCB.19.1.78. View

17.

Weller M, Wick W, Aldape K, Brada M, Berger M, Pfister S . Glioma. Nat Rev Dis Primers. 2016; 1:15017. DOI: 10.1038/nrdp.2015.17. View

18.

Zhou X, Wang R, Li X, Yu L, Hua D, Sun C . Splicing factor SRSF1 promotes gliomagenesis via oncogenic splice-switching of MYO1B. J Clin Invest. 2018; 129(2):676-693. PMC: 6355305. DOI: 10.1172/JCI120279. View

19.

Guipponi M, Scott H, Chen H, Schebesta A, Rossier C, Antonarakis S . Two isoforms of a human intersectin (ITSN) protein are produced by brain-specific alternative splicing in a stop codon. Genomics. 1998; 53(3):369-76. DOI: 10.1006/geno.1998.5521. View

20.

Wan L, Dreyfuss G . Splicing-Correcting Therapy for SMA. Cell. 2017; 170(1):5. DOI: 10.1016/j.cell.2017.06.028. View