Differentiation: the selective potentiation of chromatin domains

Development ◽  
1998 ◽  
Vol 125 (23) ◽  
pp. 4749-4755 ◽  
Author(s):  
J.A. Kramer ◽  
J.R. McCarrey ◽  
D. Djakiew ◽  
S.A. Krawetz

Potentiation is requisite for the expression of our genome. It is the mechanism of opening chromatin domains to render genes accessible to tissue-specific and ubiquitous transacting-factors that enables transcription. The results presented in this study demonstrate that modulation of stage- and cell-type-specific gene expression during mammalian spermatogenesis involves selective potentiation of testis-expressed genes that reverses their repressive state when present in the spermatogonial stem cell. This directly contrasts hematopoiesis, which acts to selectively restrict lineage potential during differentiation from its permissive stem cell. These results are key to understanding how differentiative pathways are controlled and cellular phenotypes determined. A window to their modulation is presented.


2020 ◽  
Author(s):  
Jonathan Lenz ◽  
Robert Liefke ◽  
Julianne Funk ◽  
Samuel Shoup ◽  
Andrea Nist ◽  
...  

AbstractThe generation of lineage-specific gene expression programmes that alter proliferation capacity, metabolic profile and cell type-specific functions during differentiation from multipotent stem cells to specialised cell types is crucial for development. During differentiation gene expression programmes are dynamically modulated by a complex interplay between sequence-specific transcription factors, associated cofactors and epigenetic regulators. Here, we study U-shaped (Ush), a multi-zinc finger protein that maintains the multipotency of stem cell-like hemocyte progenitors during Drosophila hematopoiesis. Using genomewide approaches we reveal that Ush binds to promoters and enhancers and that it controls the expression of three gene classes that encode proteins relevant to stem cell-like functions and differentiation: cell cycle regulators, key metabolic enzymes and proteins conferring specific functions of differentiated hemocytes. We employ complementary biochemical approaches to characterise the molecular mechanisms of Ush-mediated gene regulation. We uncover distinct Ush isoforms one of which binds the Nucleosome Remodeling and Deacetylation (NuRD) complex using an evolutionary conserved peptide motif. Remarkably, the Ush/NuRD complex specifically contributes to the repression of lineage-specific genes but does not impact the expression of cell cycle regulators or metabolic genes. This reveals a mechanism that enables specific and concerted modulation of functionally related portions of a wider gene expression programme. Finally, we use genetic assays to demonstrate that Ush and NuRD regulate enhancer activity during hemocyte differentiation in vivo and that both cooperate to suppress the differentiation of lamellocytes, a highly specialised blood cell type. Our findings reveal that Ush coordinates proliferation, metabolism and cell type-specific activities by isoform-specific cooperation with an epigenetic regulator.



BMC Urology ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Laura E Pascal ◽  
Eric W Deutsch ◽  
David S Campbell ◽  
Martin Korb ◽  
Lawrence D True ◽  
...  


PLoS Genetics ◽  
2021 ◽  
Vol 17 (2) ◽  
pp. e1009318
Author(s):  
Jonathan Lenz ◽  
Robert Liefke ◽  
Julianne Funk ◽  
Samuel Shoup ◽  
Andrea Nist ◽  
...  

The generation of lineage-specific gene expression programmes that alter proliferation capacity, metabolic profile and cell type-specific functions during differentiation from multipotent stem cells to specialised cell types is crucial for development. During differentiation gene expression programmes are dynamically modulated by a complex interplay between sequence-specific transcription factors, associated cofactors and epigenetic regulators. Here, we study U-shaped (Ush), a multi-zinc finger protein that maintains the multipotency of stem cell-like hemocyte progenitors during Drosophila hematopoiesis. Using genomewide approaches we reveal that Ush binds to promoters and enhancers and that it controls the expression of three gene classes that encode proteins relevant to stem cell-like functions and differentiation: cell cycle regulators, key metabolic enzymes and proteins conferring specific functions of differentiated hemocytes. We employ complementary biochemical approaches to characterise the molecular mechanisms of Ush-mediated gene regulation. We uncover distinct Ush isoforms one of which binds the Nucleosome Remodeling and Deacetylation (NuRD) complex using an evolutionary conserved peptide motif. Remarkably, the Ush/NuRD complex specifically contributes to the repression of lineage-specific genes but does not impact the expression of cell cycle regulators or metabolic genes. This reveals a mechanism that enables specific and concerted modulation of functionally related portions of a wider gene expression programme. Finally, we use genetic assays to demonstrate that Ush and NuRD regulate enhancer activity during hemocyte differentiation in vivo and that both cooperate to suppress the differentiation of lamellocytes, a highly specialised blood cell type. Our findings reveal that Ush coordinates proliferation, metabolism and cell type-specific activities by isoform-specific cooperation with an epigenetic regulator.



PLoS Genetics ◽  
2020 ◽  
Vol 16 (4) ◽  
pp. e1008661 ◽  
Author(s):  
Hasthi Ram ◽  
Sudeep Sahadevan ◽  
Nittaya Gale ◽  
Monica Pia Caggiano ◽  
Xiulian Yu ◽  
...  




2018 ◽  
Vol 9 (1) ◽  
Author(s):  
Takashi Ikeda ◽  
Takafusa Hikichi ◽  
Hisashi Miura ◽  
Hirofumi Shibata ◽  
Kanae Mitsunaga ◽  
...  




2019 ◽  
Author(s):  
Igor Mačinković ◽  
Ina Theofel ◽  
Tim Hundertmark ◽  
Kristina Kovač ◽  
Stephan Awe ◽  
...  

Abstract CoREST has been identified as a subunit of several protein complexes that generate transcriptionally repressive chromatin structures during development. However, a comprehensive analysis of the CoREST interactome has not been carried out. We use proteomic approaches to define the interactomes of two dCoREST isoforms, dCoREST-L and dCoREST-M, in Drosophila. We identify three distinct histone deacetylase complexes built around a common dCoREST/dRPD3 core: A dLSD1/dCoREST complex, the LINT complex and a dG9a/dCoREST complex. The latter two complexes can incorporate both dCoREST isoforms. By contrast, the dLSD1/dCoREST complex exclusively assembles with the dCoREST-L isoform. Genome-wide studies show that the three dCoREST complexes associate with chromatin predominantly at promoters. Transcriptome analyses in S2 cells and testes reveal that different cell lineages utilize distinct dCoREST complexes to maintain cell-type-specific gene expression programmes: In macrophage-like S2 cells, LINT represses germ line-related genes whereas other dCoREST complexes are largely dispensable. By contrast, in testes, the dLSD1/dCoREST complex prevents transcription of germ line-inappropriate genes and is essential for spermatogenesis and fertility, whereas depletion of other dCoREST complexes has no effect. Our study uncovers three distinct dCoREST complexes that function in a lineage-restricted fashion to repress specific sets of genes thereby maintaining cell-type-specific gene expression programmes.



2020 ◽  
Vol 87 (9) ◽  
pp. S60-S61
Author(s):  
Jiebiao Wang ◽  
Bernie Devlin ◽  
Kathryn Roeder


Sign in / Sign up

Export Citation Format

Share Document