CRISPR/Cas9 interrogation of the mouse Pcdhg gene cluster reveals a crucial isoform-specific role for Pcdhgc4

English version

Autoři: Andrew M. Garrett ^aff001; Peter J. Bosch ^aff003; David M. Steffen ^aff003; Leah C. Fuller ^aff003; Charles G. Marcucci ^aff003; Alexis A. Koch ^aff001; Preeti Bais ^aff002; Joshua A. Weiner ^aff003; Robert W. Burgess ^aff002
Působiště autorů: Department of Pharmacology and Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University, Detroit, Michigan, United States of America ^aff001; The Jackson Laboratory, Bar Harbor, Maine, United States of America ^aff002; Department of Biology and Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa, United States of America ^aff003
Vyšlo v časopise: CRISPR/Cas9 interrogation of the mouse Pcdhg gene cluster reveals a crucial isoform-specific role for Pcdhgc4. PLoS Genet 15(12): e32767. doi:10.1371/journal.pgen.1008554
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pgen.1008554

Souhrn

The mammalian Pcdhg gene cluster encodes a family of 22 cell adhesion molecules, the gamma-Protocadherins (γ-Pcdhs), critical for neuronal survival and neural circuit formation. The extent to which isoform diversity–a γ-Pcdh hallmark–is required for their functions remains unclear. We used a CRISPR/Cas9 approach to reduce isoform diversity, targeting each Pcdhg variable exon with pooled sgRNAs to generate an allelic series of 26 mouse lines with 1 to 21 isoforms disrupted via discrete indels at guide sites and/or larger deletions/rearrangements. Analysis of 5 mutant lines indicates that postnatal viability and neuronal survival do not require isoform diversity. Surprisingly, given reports that it might not independently engage in trans-interactions, we find that γC4, encoded by Pcdhgc4, is the only critical isoform. Because the human orthologue is the only PCDHG gene constrained in humans, our results indicate a conserved γC4 function that likely involves distinct molecular mechanisms.

Klíčová slova:

Sequence alignment – Mammalian genomics – Polymerase chain reaction – Apoptosis – Retina – Genome sequencing – Interneurons

Zdroje

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