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Buchser, W. J.

Publications and source records attributed to Buchser, W. J..

2 recordsLinked to original sources

Mitochondrial Phenotypes Distinguish Pathogenic MFN2 Mutations by Pooled Functional Genomics Screen

Most human genetic variation is classified as VUS - variants of uncertain significance. While advances in genome editing have allowed innovation in pooled screening platforms, many screens deal with relatively simple readouts (viability, fluorescence) and cannot identify the complex cellular phenotypes that underlie most human diseases. In this paper, we present a generalizable functional genomics platform that combines high-content imaging, machine learning, and microraft isolation in a new method termed "Raft-Seq". We highlight the efficacy of our platform by showing its ability to distinguish pathogenic point mutations of the mitochondrial regulator MFN2, even when the cellular phenotype is subtle. We also show that our platform achieves its efficacy using multiple cellular features, which can be configured on-the-fly. Raft-Seq enables a new way to perform pooled screening on sets of mutations in biologically relevant cells, with the ability to physically capture any cell with a perturbed phenotype and expand it clonally, directly from the primary screen. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=121 SRC="FIGDIR/small/434746v2_ufig1.gif" ALT="Figure 1"> View larger version (46K): org.highwire.dtl.DTLVardef@c774b4org.highwire.dtl.DTLVardef@bee63corg.highwire.dtl.DTLVardef@fd7099org.highwire.dtl.DTLVardef@eb7d87_HPS_FORMAT_FIGEXP M_FIG C_FIG Here, we address the need to evaluate the impact of numerous genetic variants. This manuscript depicts the methods of using machine learning on a biologically relevant phenotype to predict specific point mutations, followed by physically capturing those mutated cells.

genomics

Modulating Intra-Nuclear LC3 with Small Molecules Rescues Cells from a Docetaxel-Induced Phenotype

Nucleus-associated autophagy has been described as a cellular metabolic response by which nuclear material is actively degraded. This degradation occurs after stress, such as nuclear damage or the onset of tumorigenesis. Here we describe a nucleus-associated autophagic process distinct from other forms of selective autophagy in human cell lines. We found that although nuclear localization of MAP1LC3B (LC3) is not dependent on particular nuclear importins, knockdown of nuclear importins, which causes nuclear stress, can induce a nuclear autophagic response. Our characterization of this autophagic phenomenon was facilitated by chemical modulation of the process via two compounds discovered previously in a high content analysis. These small molecules bidirectionally regulate nuclear LC3 in human renal, pancreatic, and bladder cell lines. One molecule (NSC31762 or DTEP) enhances nuclear LC3 puncta and increases lysosomal targeting of LC3. This compound also decreases the nuclear envelope protein LaminB1. Another molecule (NSC279895 or DIHI) reduces the nuclear localization of LC3. Finally, we applied these chemical tools in the setting of mitotic-disruptor induced nuclear stress. The compound DIHI, shown to reduce nuclear autophagic puncta, diminished the mitotic disruptor effect. These new tools will allow for deeper exploration of nucleus-associated autophagies, and could serve as proof-of-principle in guiding new therapies for diseases involving nuclear stress.

molecular biology