Abstract

BackgroundRBM10 is an RNA binding protein involved in the regulation of transcription, alternative splicing and message stabilization. Mutations in RBM10, which maps to the X chromosome, are associated with TARP syndrome, lung and pancreatic cancers. Two predominant isoforms of RBM10 exist, RBM10v1 and RBM10v2. Both variants have alternate isoforms that differ by one valine residue, at amino acid 354 (RBM10v1) or 277 (RBM10v2). It was recently observed that a novel point mutation at amino acid 354 of RBM10v1, replacing valine with glutamic acid, correlated with preferential expression of an exon 11 inclusion variant of the proliferation regulatory protein NUMB, which is upregulated in lung cancer.FindingsWe demonstrate, using the GLC20 male-derived small cell lung cancer cell line - confirmed to have only one X chromosome - that the two (+/−) valine isoforms of RBM10v1 and RBM10v2 result from alternative splicing. Protein modeling of the RNA Recognition Motif (RRM) within which the alteration occurs, shows that the presence of valine inhibits the formation of one of the two α-helices associated with RRM tertiary structure, whereas the absence of valine supports the α-helical configuration. We then show 2-fold elevated expression of the transcripts encoding the minus valine RBM10v1 isoform in GLC20 cells, compared to those encoding the plus valine isoform. This expression correlates with preferential expression of the lung cancer-associated NUMB exon 11 inclusion variant.ConclusionsOur observations suggest that the ability of RBM10v1 to regulate alternative splicing depends, at least in part, on a structural alteration within the second RRM domain, which influences whether RBM10v1 functions to support or repress splicing. A model is presented.

Highlights

  • RBM10 is an RNA binding protein involved in the regulation of transcription, alternative splicing and message stabilization

  • Our observations suggest that the ability of RBM10 variant 1 (RBM10v1) to regulate alternative splicing depends, at least in part, on a structural alteration within the second RNA Recognition Motif (RRM) domain, which influences whether RBM10v1 functions to support or repress splicing

  • We demonstrate that the presence or absence of valine alters the tertiary structure of the second RNA Recognition Motif (RRM2) within the RBM10 protein

Read more

Summary

Introduction

RBM10 is an RNA binding protein involved in the regulation of transcription, alternative splicing and message stabilization. Mutations in RBM10, which maps to the X chromosome, are associated with TARP syndrome, lung and pancreatic cancers. Two predominant isoforms of RBM10 exist, RBM10v1 and RBM10v2. Both variants have alternate isoforms that differ by one valine residue, at amino acid 354 (RBM10v1) or 277 (RBM10v2). It was recently observed that a novel point mutation at amino acid 354 of RBM10v1, replacing valine with glutamic acid, correlated with preferential expression of an exon 11 inclusion variant of the proliferation regulatory protein NUMB, which is upregulated in lung cancer

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.