Conditionally Stabilized dCas9 Activator for Controlling Gene Expression in Human Cell Reprogramming and
Diego Balboa1, Jere Weltner1, Solja Eurola1
1Research Programs Unit, Molecular Neurology, Biomedicum Stem Cell Center, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland.
Stem Cell Reports
|September 10, 2015
Summary
CRISPR gene activators can reprogram cells by controlling pluripotency genes. A chemically controlled version enables precise manipulation of human pluripotent stem cell differentiation.
Area of Science:
- Molecular Biology
- Gene Regulation
- Stem Cell Biology
Background:
- CRISPR/Cas9 technology offers precise genome editing capabilities.
- Gene expression can be modulated using deactivated Cas9 (dCas9) fused to regulatory domains.
- Controlling pluripotency and differentiation is crucial for regenerative medicine.
Purpose of the Study:
- To develop and characterize a dCas9-based activator for human gene expression.
- To investigate the use of this activator for cell reprogramming and differentiation.
- To create a chemically inducible dCas9 activator system.
Main Methods:
- Fusion of dCas9 with VP16 activator domains to enhance gene activation.
- Targeting the OCT4 promoter with guide RNAs for reprogramming.
- Engineering a chemically controllable dCas9 activator using DHFR destabilization domain.
- Inducing endodermal differentiation of pluripotent stem cells.
Main Results:
- The dCas9-VP16 activator efficiently induced pluripotency genes in human cells.
- Transgenic OCT4 was successfully replaced using the dCas9 activator for cell reprogramming.
- A chemically controllable dCas9 activator was successfully generated.
- The destabilized dCas9 activator controlled endodermal differentiation of stem cells.
Conclusions:
- dCas9-based activators are effective tools for controlling gene expression in human cells.
- This technology enables efficient cell reprogramming and precise control over stem cell differentiation.
- Chemically inducible systems offer enhanced control for therapeutic applications.
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