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Hong, O.

Publications and source records attributed to Hong, O..

4 recordsLinked to original sources

BAG6 and RNF126 promote the degradation of cytosolic misfolded proteins that contain buried degron motifs

Missense mutations account for the majority of catalogued human disease-associated variants, and many are predicted to destabilize proteins and promote their degradation. To characterize the pathways responsible for recognizing and clearing such variants, we employed a two-pronged approach to identify both quality control components mediating turnover of misfolded proteins and the sequence elements within their substrates that drive this process. Using a panel of unstable cytosolic missense variants in proximity-labeling and RNAi-based experiments, we identified the BAG6-RNF126 pathway as contributing to the clearance of a subset of these substrates. Applying a tile-based approach to a model cytosolic protein, we uncovered strong potential degrons, including a C-terminal degron degraded in part in a BAG6- and RNF126-dependent manner. Modeling supports that this degron can be accommodated by BAG6. Together, our findings add to the growing body of evidence implicating the BAG6-RNF126 pathway as a key mediator of cytosolic protein quality control.

molecular biology↗

Oligogenic effects of 16p11.2 copy number variation on craniofacial development

A copy number variant (CNV) of 16p11.2, which encompasses 30 genes, is associated with developmental and psychiatric disorders, head size and body mass. The genetic mechanisms that underlie these associations are not understood. To elucidate the effects of genes on development, we exploited the quantitative effects of CNV on craniofacial structure in humans and model organisms. We show that reciprocal deletion and duplication of 16p11.2 have characteristic "mirror" effects on craniofacial features that are conserved in human, rat and mouse. By testing gene dosage effects on the shape of the mandible in zebrafish, we show that the distribution of effects for all individual genes is consistent with that of the CNV, and some combinations have non-additive effects. Our results suggest that, at minimum, one third of genes within the 16p11.2 region influence craniofacial development, and the facial gestalt of each CNV represents a product of 30 dosage effects. HighlightsO_LIReciprocal CNVs of 16p11.2 have mirror effects on craniofacial structure. Copy number is associated with a positive effect on nasal and mandibular regions and a negative effect on frontal regions of the face. C_LIO_LIEffects of CNV on craniofacial development in human are well conserved in rat and mouse models of 16p11.2 deletion and duplication. C_LIO_LI7/30 genes each independently have significant effects on the shape of the mandible in zebrafish; these include SPN, C16orf54, SEZ6L2, ASPHD1, TAOK2, INO80E and FAM57B. Others (MAPK3, MVP, KCTD13) have detectable effects only in combination. C_LIO_LIOverexpression of 30 genes individually showed a distribution of effects that was skewed in the same direction as that of the full duplication, suggesting that specific facial features represent the net of all individual effects combined. C_LI

genetics↗

Quantification of autism recurrence risk by direct assessment of paternal sperm mosaicism

De novo genetic mutations represent a major contributor to pediatric disease, including autism spectrum disorders (ASD), congenital heart disease, and muscular dystrophies1,2, but there are currently no methods to prevent or predict them. These mutations are classically thought to occur either at low levels in progenitor cells or at the time of fertilization1,3 and are often assigned a low risk of recurrence in siblings4,5. Here, we directly assess the presence of de novo mutations in paternal sperm and discover abundant, germline-restricted mosaicism. From a cohort of ASD cases, employing single molecule genotyping, we found that four out of 14 fathers were germline mosaic for a putatively causative mutation transmitted to the affected child. Three of these were enriched or exclusively present in sperm at high allelic fractions (AF; 7-15%); and one was recurrently transmitted to two additional affected children, representing clinically actionable information. Germline mosaicism was further assessed by deep (>90x) whole genome sequencing of four paternal sperm samples, which detected 12/355 transmitted de novo single nucleotide variants that were mosaic above 2% AF, and more than two dozen additional, non-transmitted mosaic variants in paternal sperm. Our results demonstrate that germline mosaicism is an underestimated phenomenon, which has important implications for clinical practice and in understanding the basis of human disease. Genetic analysis of sperm can assess individualized recurrence risk following the birth of a child with a de novo disease, as well as the risk in any male planning to have children.

genetics↗

Paternally inherited noncoding structural variants contribute to autism

The genetic architecture of autism spectrum disorder (ASD) is known to consist of contributions from gene-disrupting de novo mutations and common variants of modest effect. We hypothesize that the unexplained heritability of ASD also includes rare inherited variants with intermediate effects. We investigated the genome-wide distribution and functional impact of structural variants (SVs) through whole genome analysis ([≥]30X coverage) of 3,169 subjects from 829 families affected by ASD. Genes that are intolerant to inactivating variants in the exome aggregation consortium (ExAC) were depleted for SVs in parents, specifically within fetal-brain promoters, UTRs and exons. Rare paternally-inherited SVs that disrupt promoters or UTRs were over-transmitted to probands (P = 0.0013) and not to their typically-developing siblings. Recurrent functional noncoding deletions implicate the gene LEO1 in ASD. Protein-coding SVs were also associated with ASD (P = 0.0025). Our results establish that rare inherited SVs predispose children to ASD, with differing contributions from each parent.

genomics↗