PSD-95 is post-transcriptionally repressed during early neural development by PTBP1 and PTBP2
2012; Nature Portfolio; Volume: 15; Issue: 3 Linguagem: Inglês
10.1038/nn.3026
ISSN1546-1726
AutoresSika Zheng, Erin E. Gray, Geetanjali Chawla, Bo Porse, Thomas J. O’Dell, Douglas L. Black,
Tópico(s)MicroRNA in disease regulation
ResumoPostsynaptic density protein 95 (PSD-95) is essential for synaptic maturation and plasticity. Although its synaptic regulation has been widely studied, the control of PSD-95 cellular expression is not understood. We found that Psd-95 was controlled post-transcriptionally during neural development. Psd-95 was transcribed early in mouse embryonic brain, but most of its product transcripts were degraded. The polypyrimidine tract binding proteins PTBP1 and PTBP2 repressed Psd-95 (also known as Dlg4) exon 18 splicing, leading to premature translation termination and nonsense-mediated mRNA decay. The loss of first PTBP1 and then of PTBP2 during embryonic development allowed splicing of exon 18 and expression of PSD-95 late in neuronal maturation. Re-expression of PTBP1 or PTBP2 in differentiated neurons inhibited PSD-95 expression and impaired the development of glutamatergic synapses. Thus, expression of PSD-95 during early neural development is controlled at the RNA level by two PTB proteins whose sequential downregulation is necessary for synapse maturation.
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