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Dagliyan, O.

Publications and source records attributed to Dagliyan, O..

2 recordsLinked to original sources

Development of a protocol utilizing single-cell analysis for the differentiation of human iPSCs into SOX6+ midbrain dopaminergic neurons.

Parkinsons disease (PD) is characterized by the progressive loss of midbrain dopaminergic (mDA) neurons, leading to severe debilitating motor impairment. Recent single-cell analyses have revealed that specific mDA subpopulations, such as SOX6 AGTR1 neurons, are most vulnerable to degeneration. Current human pluripotent stem cell differentiation protocols fail to selectively generate these subtypes. Here, we describe a multiomic-guided strategy that enriches SOX6+ mDA neurons by combining enhancing Sonic Hedgehog agonism with prolonged Wnt activation. This approach accelerates floor plate specification, increases expression of mDA developmental markers, and substantially increases the yield of SOX6 mature mDA neurons compared to prior attempts. Following intrastriatal transplantation into hemiparkinsonian mice, these cells restored motor function in approximately 4 months and generated grafts containing SOX6 A9-like neurons. Our work thus establishes a reproducible differentiation platform for generating the PD-susceptible mDA subtype, providing a foundation for precision disease modelling and subtype-targeted cell replacement therapies.

cell biology↗

Rational design and implementation of a chemically inducible hetero-trimerization system

Chemically inducible dimerization (CID) uses a small molecule to induce binding of two different proteins. CID tools exemplified by the FKBP/FRB/rapamycin system have been widely employed to probe molecular events inside and outside cells. While various CID tools are available, chemically inducible trimerization (CIT) has not been developed, due to inherent challenges in designing or identifying a chemical that simultaneously binds three proteins with high affinity and target specificity. Nevertheless, by introducing a third recruitable component, CIT could enable versatile applications. Here, we devised the CIT by rationally splitting FRB and FKBP. Based on cellular and structural datasets, select split pairs of FRB or FKBP underwent efficient trimerization with full length FKBP or FRB, respectively, upon addition of rapamycin. We also demonstrated its potential for cellular applications by rapidly inducing tri-organellar plasma membrane-ER-mitochondria junctions, and by perturbing intended membrane lipids exclusively at the plasma membrane-ER membrane contact sites. By conferring one additional condition to what is achievable with CID, CIT expands the types of manipulation in single live cells, to address cell biology questions otherwise intractable, and engineer cell functions for future synthetic biology applications.

cell biology↗