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Biology subjects

Cotney, J. L.

Publications and source records attributed to Cotney, J. L..

2 recordsLinked to original sources

Dkk2 interacts with Pax9 in palate mesenchyme to pattern and tune osteogenesis

Multiple genetic and environmental etiologies contribute to the pathogenesis of cleft palate, which constitutes the most common among the inherited disorders of the craniofacial complex. Insights into the molecular mechanisms regulating osteogenic differentiation and patterning in the palate during embryogenesis are limited and needed for the development of innovative diagnostics and cures. This study utilized the Pax9-/- mouse model with a consistent phenotype of cleft secondary palate to investigate the role of Pax9 in the process of palatal osteogenesis. While prior research had identified upregulation of Wnt pathway modulators Dkk1 and Dkk2 in Pax9-/- palate mesenchyme, limitations of spatial resolution and technology restricted a more robust analysis. Here, data from single-nucleus transcriptomics and chromatin accessibility assays validated by in situ highly multiplex targeted single-cell spatial profiling technology suggest a distinct relationship between Pax9+ and osteogenic populations. Loss of Pax9 results in spatially restricted osteogenic domains bounded by Dkk2, which normally interfaces with Pax9 in the mesenchyme. These results suggest that Pax9-dependent Wnt signaling modulators influence osteogenic programming during palate formation, potentially contributing to the observed cleft palate phenotype.

developmental biology↗

Specific ZNF274 binding interference at SNORD116 activates the maternal transcripts in Prader-Willi syndrome neurons

Prader-Willi syndrome (PWS) is characterized by neonatal hypotonia, developmental delay, and hyperphagia/obesity. This disorder is caused by the absence of paternally-expressed gene products from chromosome 15q11-q13. We previously demonstrated that knocking out ZNF274, a KRAB-domain zinc finger protein capable of recruiting epigenetic machinery to deposit the H3K9me3 repressive histone modification, can activate expression from the normally silent maternal allele of SNORD116 in neurons derived from PWS iPSCs. However, ZNF274 has many other targets in the genome in addition to SNORD116. Depleting ZNF274 will surely affect the expression of other important genes and disrupt other pathways. Here we used CRISPR/Cas9 to delete ZNF274 binding sites at the SNORD116 locus to determine whether activation of the maternal copy of SNORD116 could be achieved without altering ZNF274 protein levels. We obtained similar activation of gene expression from the normally silenced maternal allele in neurons derived from PWS iPSCs, compared to ZNF274 knockout, demonstrating that ZNF274 is directly involved in the repression of SNORD116. These results suggest that interfering with ZNF274 binding at the maternal SNORD116 locus is a potential therapeutic strategy for PWS.

genetics↗