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Cheng, l.

Publications and source records attributed to Cheng, l..

2 recordsLinked to original sources

POGZ controls embryonic stem cell self-renewal and pluripotency by association with esBAF and HP1

POGZ, which encodes a multi-domain transcription factor, has been found frequently mutated in neurodevelopmental disorders, particularly autism spectrum disorder (ASD) and intellectual disability (ID). However, little is known about its functions in embryonic stem cells (ESCs) and in transcriptional regulation. Here, we show that POGZ plays key roles in the maintenance of ESCs by association with the SWI-SNF (BAF) chromatin remodeler complex and heterochromatin protein 1 (HP1) proteins. Loss of POGZ induces differentiation of ESCs, likely by up-regulation of primitive endoderm and mesoderm lineage genes and by down-regulation of pluripotency-related and cell cycle genes. Genome-wide binding analysis shows that POGZ is primarily localized to gene promoter and enhancer regions where POGZ is required to maintain an open chromatin. Regulation of chromatin under control of POGZ depends on esBAF complex. Furthermore, there is an extensive overlap of POGZ and OCT4 peaks genome-wide, and both factors interact with each other. We propose that POGZ is an important pluripotency-associated factor, and its absence causes failure to maintain a proper ESC-specific chromatin state and transcriptional circuitry, which eventually leads to loss of ESC phenotype. Our work provides important insights into the roles of POGZ in the maintenance of ESC identity as well as regulation of transcription, which will be useful for understanding the etiology of neurodevelopmental disorders by POGZ mutation.

developmental biology

HTT silencing delays onset and slows progression of Huntington disease like phenotype: Monitoring with a novel neurovascular biomarker

Huntingtons disease (HD) is a dominantly inherited, fatal neurodegenerative disorder caused by a CAG expansion in the Huntingtin (HTT) gene, coding for pathologic mutant HTT protein (mHTT). Because of its gain-of-function mechanism and monogenic etiology, strategies to lower HTT are being actively investigated as disease-modifying therapies. Most approaches are currently targeted at the manifest HD stage, when clinical outcomes are used to evaluate the effectiveness of therapy. However, as almost 50% of striatal volume has been lost at the time of onset of manifest HD it would be preferable to begin therapy in the premanifest period. An unmet challenge is how to evaluate therapeutic efficacy before the presence of clinical symptoms as outcome measures. To address this, we have been developing more sensitive biomarkers such as functional neuroimaging with the goal of identifying noninvasive biomarkers that provide insight into the best time to introduce HTT-lowering treatment. In this study, we mapped the temporal trajectories of arteriolar cerebral blood volumes (CBVa) using inflow-based vascular-space-occupancy (iVASO) MRI technique in an HD mouse model. Significantly elevated CBVa was evident in premanifest zQ175 HD mice prior to motor deficits and striatal atrophy, recapitulating altered CBVa in human premanifest HD. CRISPR/Cas9-mediated non-allele-specific HTT silencing in striatal neurons restored altered CBVa in premanifest zQ175 mice, delayed onset of striatal atrophy, and slowed the progression of motor phenotype and brain pathology. This study showed the potential of CBVa as a noninvasive fMRI biomarker for premanifest HD clinical trials and demonstrates long-term benefits of introducing an HTT lowering treatment in the premanifest HD.

neuroscience