Biology subjects

Pozner, T.

Publications and source records attributed to Pozner, T..

3 recordsLinked to original sources

bioRxiv2025

A new NHGRI Sample Repository for Human Genetic Research collection of induced pluripotent stem cell lines.

We describe here a new NHGRI Sample Repository for Human Genetic Research collection of induced pluripotent stem cell (iPSC) lines reprogrammed from whole blood derived peripheral blood mononuclear cells (PBMCs). PBMCs were reprogrammed using Sendai viral vectors carrying transcription factors OCT4, SOX2, KLF4, and c-MYC. All iPSC lines exhibit a normal karyotype, express common stemness and pluripotency markers, and demonstrate the ability to differentiate into cell types representing all three germ layers. This iPSC collection (n=7) will have accompanying public, near telomere to telomere genomic data through the Human Pangenome Reference Consortium, and provides an invaluable new in vitro resource for studying common genetic and genomic variation and its functional implications.

cell biology↗

bioRxiv2025

New iPSC resource with long-read whole genome sequencing characterizations for enhanced in vitro modeling

Here we present a new iPSC resource of apparently healthy subject biospecimens available to the research community through the National Institute of General Medical Sciences Human Genetic Cell Repository (NIGMS Repository). This resource includes five iPSCs and matched parental cell lines with accompanying publicly available, HiFi whole-genome sequencing data. Structural variant (SV) and single nucleotide variant (SNV) concordance between iPSC and parental lines was generally high; however, we found a notable reduction in concordance between the iPSC reprogrammed with retroviral reprogramming and its parental line consistent with previous work showing newer Sendai approaches to be more robust in preserving genomic integrity. This iPSC resource additionally includes pharmacogenomic and human leukocyte antigen (HLA) gene annotations as well as a set of user-friendly, web-based search tools to visualize and explore SVs and SNVs. This new resource is designed to offer a highly characterized set of in vitro models for research into cell-type specific functional characterization of genetic, genomic and pharmacogenomic variation. More generally, these renewable biospecimens and genomic data search tools are available to the scientific community to support high-quality and reproducible biomedical research.

genomics↗

bioRxiv2023

Human iPSC 4R tauopathy model uncovers modifiers of tau propagation

Tauopathies are age-associated neurodegenerative diseases whose mechanistic underpinnings remain elusive, partially due to lack of appropriate human models. Current human induced pluripotent stem cell (hiPSC)-derived neurons express very low levels of 4-repeat (4R)-tau isoforms that are normally expressed in adult brain. Here, we engineered new iPSC lines to express 4R-tau and 4R-tau carrying the P301S MAPT mutation when differentiated into neurons. 4R-P301S neurons display progressive Tau inclusions upon seeding with Tau fibrils and recapitulate features of tauopathy phenotypes, including shared transcriptomic signatures, autophagic body accumulation, and impaired neuronal activity. A CRISPRi screen of genes associated with Tau pathobiology identified over 500 genetic modifiers of Tau-seeding-induced Tau propagation, including retromer VPS29 and the UFMylation cascade as top modifiers. In AD brains, the UFMylation cascade is altered in neurofibrillary-tangle-bearing neurons. Inhibiting the UFMylation cascade suppressed seeding-induced Tau propagation. This model provides a powerful platform to identify novel therapeutic strategies for 4R tauopathy.

neuroscience↗