This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Singh, N. K.
Right arrow Articles by Singh, R. N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Singh, N. K.
Right arrow Articles by Singh, R. N.

 Previous Article  |  Next Article 

Molecular and Cellular Biology, February 2006, p. 1333-1346, Vol. 26, No. 4
0270-7306/06/$08.00+0     doi:10.1128/MCB.26.4.1333-1346.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Splicing of a Critical Exon of Human Survival Motor Neuron Is Regulated by a Unique Silencer Element Located in the Last Intron

Nirmal K. Singh ,{ddagger},{dagger} Natalia N. Singh,{dagger} Elliot J. Androphy, and Ravindra N. Singh*

Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts

Received 3 August 2005/ Returned for modification 5 September 2005/ Accepted 4 December 2005

Humans have two nearly identical copies of the Survival Motor Neuron (SMN) gene, SMN1 and SMN2. In spinal muscular atrophy (SMA), SMN2 is not able to compensate for the loss of SMN1 due to exclusion of exon 7. Here we describe a novel inhibitory element located immediately downstream of the 5' splice site in intron 7. We call this element intronic splicing silencer N1 (ISS-N1). Deletion of ISS-N1 promoted exon 7 inclusion in mRNAs derived from the SMN2 minigene. Underlining the dominant role of ISS-N1 in exon 7 skipping, abrogation of a number of positive cis elements was tolerated when ISS-N1 was deleted. Confirming the silencer function of ISS-N1, an antisense oligonucleotide against ISS-N1 restored exon 7 inclusion in mRNAs derived from the SMN2 minigene or from endogenous SMN2. Consistently, this oligonucleotide increased the levels of SMN protein in SMA patient-derived cells that carry only the SMN2 gene. Our findings underscore for the first time the profound impact of an evolutionarily nonconserved intronic element on SMN2 exon 7 splicing. Considering that oligonucleotides annealing to intronic sequences do not interfere with exon-junction complex formation or mRNA transport and translation, ISS-N1 provides a very specific and efficient therapeutic target for antisense oligonucleotide-mediated correction of SMN2 splicing in SMA.

* Corresponding author. Mailing address: Department of Medicine (LRB 326), University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605. Phone: (508) 856-1333. Fax: (508) 856-6797. E-mail: Ravindra.Singh{at}umassmed.edu.

{ddagger} Present address: Division of Investigative Pathology, Scott & White Clinic and Texas A&M University System Health Science Center, College of Medicine, Temple, TX 76504.

{dagger} N.K.S. and N.N.S. contributed equally to this work.

Molecular and Cellular Biology, February 2006, p. 1333-1346, Vol. 26, No. 4
0022-538X/06/$08.00+0     doi:10.1128/MCB.26.4.1333-1346.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Hastings, M. L., Berniac, J., Liu, Y. H., Abato, P., Jodelka, F. M., Barthel, L., Kumar, S., Dudley, C., Nelson, M., Larson, K., Edmonds, J., Bowser, T., Draper, M., Higgins, P., Krainer, A. R. (2009). Tetracyclines That Promote SMN2 Exon 7 Splicing as Therapeutics for Spinal Muscular Atrophy. Sci Transl Med 1: 5ra12-5ra12 [Abstract] [Full Text]  
  • Williams, J. H., Schray, R. C., Patterson, C. A., Ayitey, S. O., Tallent, M. K., Lutz, G. J. (2009). Oligonucleotide-Mediated Survival of Motor Neuron Protein Expression in CNS Improves Phenotype in a Mouse Model of Spinal Muscular Atrophy. J. Neurosci. 29: 7633-7638 [Abstract] [Full Text]  
  • Baughan, T. D., Dickson, A., Osman, E. Y., Lorson, C. L. (2009). Delivery of bifunctional RNAs that target an intronic repressor and increase SMN levels in an animal model of spinal muscular atrophy. Hum Mol Genet 18: 1600-1611 [Abstract] [Full Text]  
  • Martins de Araujo, M., Bonnal, S., Hastings, M. L., Krainer, A. R., Valcarcel, J. (2009). Differential 3' splice site recognition of SMN1 and SMN2 transcripts by U2AF and U2 snRNP. RNA 15: 515-523 [Abstract] [Full Text]  
  • Papp, L. V., Wang, J., Kennedy, D., Boucher, D., Zhang, Y., Gladyshev, V. N., Singh, R. N., Khanna, K. K. (2008). Functional characterization of alternatively spliced human SECISBP2 transcript variants. Nucleic Acids Res 36: 7192-7206 [Abstract] [Full Text]  
  • Chen, H.-H., Chang, J.-G., Lu, R.-M., Peng, T.-Y., Tarn, W.-Y. (2008). The RNA Binding Protein hnRNP Q Modulates the Utilization of Exon 7 in the Survival Motor Neuron 2 (SMN2) Gene. Mol. Cell. Biol. 28: 6929-6938 [Abstract] [Full Text]  
  • Wang, Z., Burge, C. B. (2008). Splicing regulation: From a parts list of regulatory elements to an integrated splicing code. RNA 14: 802-813 [Abstract] [Full Text]  
  • Sumner, C. J. (2007). Molecular Mechanisms of Spinal Muscular Atrophy. J Child Neurol 22: 979-989 [Abstract]  
  • Kashima, T., Rao, N., Manley, J. L. (2007). An intronic element contributes to splicing repression in spinal muscular atrophy. Proc. Natl. Acad. Sci. USA 104: 3426-3431 [Abstract] [Full Text]  
  • Singh, N. N., Singh, R. N., Androphy, E. J. (2007). Modulating role of RNA structure in alternative splicing of a critical exon in the spinal muscular atrophy genes. Nucleic Acids Res 35: 371-389 [Abstract] [Full Text]  
  • Buratti, E., Baralle, M., Baralle, F. E. (2006). Defective splicing, disease and therapy: searching for master checkpoints in exon definition. Nucleic Acids Res 34: 3494-3510 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»