Aclarubicin treatment restores SMN levels to cells derived from type I spinal muscular atrophy patients.
Proximal spinal muscular atrophy (SMA) is a common motor neuron disorder caused by mutation of the telomeric survival of motor neuron gene SMN1. The centromeric survival of motor neuron SMN2 gene is retained in all SMA patients but does not produce sufficient SMN protein to prevent the development of clinical symptoms. The SMN1 and SMN2 genes differ functionally by a single nucleotide change. This change affects the efficiency with which exon 7 is incorporated into the mRNA transcript. Thus, SMN2 produces less full-length mRNA and protein than SMN1. We have screened a library of compounds in order to identify ones that can alter the splicing pattern of the SMN2 gene. Here, we report that the compound aclarubicin increases the retention of exon 7 into the SMN2 transcript. We show that aclarubicin effectively induces incorporation of exon 7 into SMN2 transcripts from the endogenous gene in type I SMA fibroblasts as well as into transcripts from a SMN2 minigene in the motor neuron cell line NSC34. In type I fibroblasts, treatment resulted in an increase in SMN protein and gems to normal levels. Our results suggest that alteration of splicing pattern represents a new approach to modification of gene expression in disease treatment and demonstrate the feasibility of high throughput screens to detect compounds that affect the splicing pattern of a gene.
Andreassi
C
C
Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, OH 43210, USA.
Jarecki
J
J
Zhou
J
J
Coovert
D D
DD
Monani
U R
UR
Chen
X
X
Whitney
M
M
Pollok
B
B
Zhang
M
M
Androphy
E
E
Burghes
A H
AH
D015250:Aclarubicin / Q000494:pharmacology*; D017398:Alternative Splicing / Q000187:drug effects; D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D017362:Cyclic AMP Response Element-Binding Protein; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical; D005091:Exons; D005240:Feasibility Studies; D005347:Fibroblasts; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D009046:Motor Neurons / Q000187:drug effects / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055532:SMN Complex Proteins; D014897:Spinal Muscular Atrophies of Childhood / Q000188:drug therapy* / Q000235:genetics; D055533:Survival of Motor Neuron 1 Protein; D055540:Survival of Motor Neuron 2 Protein; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection
D017362:Cyclic AMP Response Element-Binding Protein; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D055532:SMN Complex Proteins; C526471:SMN1 protein, human; C526477:SMN2 protein, human; C526472:Smn1 protein, mouse; D055533:Survival of Motor Neuron 1 Protein; D055540:Survival of Motor Neuron 2 Protein; D015250:Aclarubicin