Transcriptional repression of PTEN in neural cells using CRISPR/dCas9 epigenetic editing

• Published in: Scientific reports Vol. 10; no. 1; p. 11393
• Main Authors: Moses, C, Hodgetts, S I, Nugent, F, Ben-Ary, G, Park, K K, Blancafort, P, Harvey, A R
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 09.07.2020; Nature Publishing Group UK
• Subjects: 5' Untranslated Regions; 5' Untranslated Regions - genetics; Animals; Axonogenesis; Axons - physiology; Cell culture; Cell Line, Tumor; Central nervous system; CRISPR; CRISPR-Cas Systems - genetics; Deacetylation; DNA methylation; Epigenetics; Gene Editing - methods; Gene silencing; Genetic Therapy - methods; Genetic Vectors - genetics; gRNA; HEK293 Cells; Humans; Inhibitory postsynaptic potentials; Lentivirus - genetics; Nerve growth factor; Nerve Regeneration - genetics; Neural crest; Neural networks; Neuronal Outgrowth - genetics; Optic Nerve - physiology; Optic Nerve Injuries - therapy; Promoter Regions, Genetic - genetics; PTEN Phosphohydrolase - genetics; PTEN protein; Rats; Recovery of function; Regeneration; Repressor Proteins - genetics; RNA Interference; RNA, Guide, CRISPR-Cas Systems - genetics; RNA, Small Interfering - metabolism; Spinal Cord Injuries - therapy; Transcription, Genetic; Transduction, Genetic - methods; Trauma
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-68257-y

After damage to the adult mammalian central nervous system (CNS), surviving neurons have limited capacity to regenerate and restore functional connectivity. Conditional genetic deletion of PTEN results in robust CNS axon regrowth, while PTEN repression with short hairpin RNA (shRNA) improves regeneration but to a lesser extent, likely due to suboptimal PTEN mRNA knockdown using this approach. Here we employed the CRISPR/dCas9 system to repress PTEN transcription in neural cells. We targeted the PTEN proximal promoter and 5' untranslated region with dCas9 fused to the repressor protein Krüppel-associated box (KRAB). dCas9-KRAB delivered in a lentiviral vector with one CRISPR guide RNA (gRNA) achieved potent and specific PTEN repression in human cell line models and neural cells derived from human iPSCs, and induced histone (H)3 methylation and deacetylation at the PTEN promoter. The dCas9-KRAB system outperformed a combination of four shRNAs targeting the PTEN transcript, a construct previously used in CNS injury models. The CRISPR system also worked more effectively than shRNAs for Pten repression in rat neural crest-derived PC-12 cells, and enhanced neurite outgrowth after nerve growth factor stimulation. PTEN silencing with CRISPR/dCas9 epigenetic editing may provide a new option for promoting axon regeneration and functional recovery after CNS trauma.