lo 3. PcG in adult stem cells

What is the INK4A-ARF locus?

The CDKN2A locus that encodes INK4A/ARF genes, which are key targets of PcG in regulating cell cycle.

How does BMI1 (PCGF4) affect hematopoietic stem cells?

BMI1 mediates enhanced self-renewal of hematopoietic stem cells.

What is the role of BMI1 in neural stem cells?

BMI1 is required for neural stem cell self-renewal.

What is the primary mechanism for BMI1 function in HSCs and NSCs?

It represses the CDKN2A locus (Ink4a and Arf).

What is the role of PRC1 in intestinal stem cells (ISCs)?

PRC1 loss depletes ISC population and prevents regeneration of intestinal crypt.

Is PRC2 essential in intestinal stem cells?

No, PRC2 is not essential in ISCs but is essential in cell fate decision between secretory cells and other cell types.

What is the PRC2 phenotype in intestinal stem cells dependent on?

The CDKN2A locus.

What is the PRC1 phenotype in intestinal stem cells independent of?

The CDKN2A locus.

What genes does PRC1 repress in intestinal stem cells?

Cell fate transcription factors (Zic family genes).

What defines intestinal stem cells?

They are defined by Lgr5 expression.

What happens to hair follicle stem cells when PRC1 (Ring1a/b) is lost?

Arrested hair follicle growth and defective Lgr5+ HFSC differentiation.

What is the consequence of Ring1a/b loss in hair follicle stem cells?

Upregulation of non-lineage genes.

What happens in Bmi1-null mice in terms of enamel production?

Defective enamel production due to fewer stem cells from upregulation of Ink4a/Arf and upregulation of Hox genes.

How does BMI1 overexpression affect age-related anemia?

It reduces age-related anemia and attenuates age-related HSC function decline.

What is the role of PRC1 in epidermal stem cells?

PRC1 fine-tunes gene repression and activation to safeguard skin development and stem cell specification.

What happens when EED is knocked out in hematopoietic cells?

Thymic and splenic atrophy, pale bone marrow, hematopoietic dysplasia.

What happens when Jarid2 is knocked out in interfollicular epidermis and hair follicles?

Defective epidermal thickness and delayed hair cycle.

What is the effect of PHF19 loss in hematopoietic cells?

High penetrance of splenomegaly, upregulation of retinoic acid pathway, downregulation of Myc network.

What does PRC1 loss in different stem cell compartments activate?

A common transcriptional program with cell type-dependent outcomes.

What is the role of PRC1 in incisors?

Ring1a/b loss causes defective enamel and dentin formation with reduced proliferation of mesenchymal transit amplifying cel