The transcription factor dHAND is a downstream effector of BMPs in sympathetic neuron specification

Development ◽  
2000 ◽  
Vol 127 (18) ◽  
pp. 4073-4081 ◽  
Author(s):  
M.J. Howard ◽  
M. Stanke ◽  
C. Schneider ◽  
X. Wu ◽  
H. Rohrer

The dHAND basic helix-loop-helix transcription factor is expressed in neurons of sympathetic ganglia and has previously been shown to induce the differentiation of catecholaminergic neurons in avian neural crest cultures. We now demonstrate that dHAND expression is sufficient to elicit the generation of ectopic sympathetic neurons in vivo. The expression of the dHAND gene is controlled by bone morphogenetic proteins (BMPs), as suggested by BMP4 overexpression in vivo and in vitro, and by noggin-mediated inhibition of BMP function in vivo. The timing of dHAND expression in sympathetic ganglion primordia, together with the induction of dHAND expression in response to Phox2b implicate a role for dHAND as transcriptional regulator downstream of Phox2b in BMP-induced sympathetic neuron differentiation.

Development ◽  
1995 ◽  
Vol 121 (8) ◽  
pp. 2361-2371
Author(s):  
A.K. Hall ◽  
S.E. MacPhedran

Adult rat sympathetic neurons can possess specific neuropeptides utilized as cotransmitters along with norepinephrine, but the factors that regulate their expression remain unknown. 60% of adult rat superior cervical ganglion (SCG) neurons express neuropeptide Y (NPY) in vivo. To determine whether the restricted expression was an intrinsic property of sympathetic ganglia, we examined if embryonic sympathetic precursors gave rise to NPY immunoreactive (-IR) neurons in vitro. After one week in culture, 60% of neurons derived from the E14.5 rat SCG were NPY-IR. Thus, ganglia isolated before peripheral target contact or preganglionic innervation were capable of regulating NPY expression both in the number of neurons with NPY and in the developmental timing of NPY expression. To determine if the restricted expression of NPY was a reflection of neuroblasts committed to an NPY fate, SCG precursors were labeled with a replication incompetent retrovirus carrying lacZ, and NPY expression in lacZ-labeled clones examined after one week. Two thirds of neuronal clones obtained were uniformly NPY-IR; that is, all neurons in a clone either possessed or lacked NPY. One-third of the neuronal clones were mixed and contained both neurons with and without NPY. We provide a novel demonstration that both lineage and environmental cues contribute to neuropeptide phenotype.


2021 ◽  
pp. 1-9
Author(s):  
Huei-Ying Chen ◽  
Joseph F. Bohlen ◽  
Brady J. Maher

Transcription factor 4 (TCF4, also known as ITF2 or E2-2) is a type I basic helix-loop-helix transcription factor. Autosomal dominant mutations in TCF4 cause Pitt-Hopkins syndrome (PTHS), a rare syndromic form of autism spectrum disorder. In this review, we provide an update on the progress regarding our understanding of TCF4 function at the molecular, cellular, physiological, and behavioral levels with a focus on phenotypes and therapeutic interventions. We examine upstream and downstream regulatory networks associated with TCF4 and discuss a range of in vitro and in vivo data with the aim of understanding emerging TCF4-specific mechanisms relevant for disease pathophysiology. In conclusion, we provide comments about exciting future avenues of research that may provide insights into potential new therapeutic targets for PTHS.


2001 ◽  
Vol 21 (2) ◽  
pp. 524-533 ◽  
Author(s):  
E. Claire Roberts ◽  
Richard W. Deed ◽  
Toshiaki Inoue ◽  
John D. Norton ◽  
Andrew D. Sharrocks

ABSTRACT The Id subfamily of helix-loop-helix (HLH) proteins plays a fundamental role in the regulation of cellular proliferation and differentiation. The major mechanism by which Id proteins are thought to inhibit differentiation is through interaction with other HLH proteins and inhibition of their DNA-binding activity. However, Id proteins have also been shown to interact with other proteins involved in regulating cellular proliferation and differentiation, suggesting a more widespread regulatory function. In this study we demonstrate functional interactions between Id proteins and members of the Pax-2/-5/-8 subfamily of paired-domain transcription factors. Members of the Pax transcription factor family have key functions in regulating several developmental processes exemplified by B lymphopoiesis, in which Pax-5 plays an essential role. Id proteins bind to Pax proteins in vitro and in vivo. Binding occurs through the paired DNA-binding domain of the Pax proteins and results in the disruption of DNA-bound complexes containing Pax-2, Pax-5, and Pax-8. In vivo, Id proteins modulate the transcriptional activity mediated by Pax-5 complexes on the B-cell-specific mb-1 promoter. Our results therefore demonstrate a novel facet of Id function in regulating cellular differentiation by functionally antagonizing the action of members of the Pax transcription factor family.


2018 ◽  
Vol 3 ◽  
pp. 125 ◽  
Author(s):  
Laura J.A. Hardwick ◽  
Anna Philpott

The proneural basic-helix-loop-helix (bHLH) transcription factor Ascl1 is a master regulator of neurogenesis in both central and peripheral nervous systems in vivo, and is a central driver of neuronal reprogramming in vitro. Over the last three decades, assaying primary neuron formation in Xenopus embryos in response to transcription factor overexpression has contributed to our understanding of the roles and regulation of proneural proteins like Ascl1, with homologues from different species usually exhibiting similar functional effects. Here we demonstrate that the mouse Ascl1 protein is twice as active as the Xenopus protein in inducing neural-β-tubulin expression in Xenopus embryos, despite there being little difference in protein accumulation or ability to undergo phosphorylation, two properties known to influence Ascl1 function. This superior activity of the mouse compared to the Xenopus protein is dependent on the presence of the non-conserved N terminal region of the protein, and indicates species-specific regulation that may necessitate care when interpreting results in cross-species experiments.


2010 ◽  
Vol 30 (11) ◽  
pp. 2737-2749 ◽  
Author(s):  
Emmanuelle Huillard ◽  
Léa Ziercher ◽  
Olivier Blond ◽  
Michael Wong ◽  
Jean-Christophe Deloulme ◽  
...  

ABSTRACT Genetic programs that govern neural stem/progenitor cell (NSC) proliferation and differentiation are dependent on extracellular cues and a network of transcription factors, which can be regulated posttranslationally by phosphorylation. However, little is known about the kinase-dependent pathways regulating NSC maintenance and oligodendrocyte development. We used a conditional knockout approach to target the murine regulatory subunit (beta) of protein kinase casein kinase 2 (CK2β) in embryonic neural progenitors. Loss of CK2β leads to defects in proliferation and differentiation of embryonic NSCs. We establish CK2β as a key positive regulator for the development of oligodendrocyte precursor cells (OPCs), both in vivo and in vitro. We show that CK2β directly interacts with the basic helix-loop-helix (bHLH) transcription factor Olig2, a critical modulator of OPC development, and activates the CK2-dependent phosphorylation of its serine-threonine-rich (STR) domain. Finally, we reveal that the CK2-targeted STR domain is required for the oligodendroglial function of Olig2. These findings suggest that CK2 may control oligodendrogenesis, in part, by regulating the activity of the lineage-specific transcription factor Olig2. Thus, CK2β appears to play an essential and uncompensated role in central nervous system development.


Development ◽  
1998 ◽  
Vol 125 (23) ◽  
pp. 4791-4801
Author(s):  
M. Geissen ◽  
S. Heller ◽  
D. Pennica ◽  
U. Ernsberger ◽  
H. Rohrer

Sympathetic ganglia are composed of noradrenergic and cholinergic neurons. The differentiation of cholinergic sympathetic neurons is characterized by the expression of choline acetyltransferase (ChAT) and vasoactive intestinal peptide (VIP), induced in vitro by a subfamily of cytokines, including LIF, CNTF, GPA, OSM and cardiotrophin-1 (CT-1). To interfere with the function of these neuropoietic cytokines in vivo, antisense RNA for gp130, the common signal-transducing receptor subunit for neuropoietic cytokines, was expressed in chick sympathetic neurons, using retroviral vectors. A strong reduction in the number of VIP-expressing cells, but not of cells expressing ChAT or the adrenergic marker tyrosine hydroxylase (TH), was observed. These results reveal a physiological role of neuropoietic cytokines for the control of VIP expression during the development of cholinergic sympathetic neurons.


1998 ◽  
Vol 18 (12) ◽  
pp. 6930-6938 ◽  
Author(s):  
I. Aksan ◽  
C. R. Goding

ABSTRACT The development of melanocytes, which are pigment-producing cells responsible for skin, hair, and eye color, is absolutely dependent on the action of the microphthalmia basic helix-loop-helix–leucine zipper (bHLH-LZ) transcription factor (Mi); mice lacking a functional Mi protein are entirely devoid of pigment cells. Mi has been shown to activate transcription of the tyrosinase,TRP-1, TRP-2, and QNR-71 genes through specific E-box elements, most notably the highly conserved M box. We investigated the mechanism which enables Mi to be recruited specifically to a restricted subset of E boxes in target promoters while being prevented from binding E-box elements in other promoters. We show both in vitro and in vivo that the presence of a T residue flanking a CATGTG E box is an essential determinant of the ability of Mi to bind DNA, and we successfully predict that the CATGTG E box from the P gene would not bind Mi. In contrast, no specific requirement for the sequences flanking a CACGTG E box was observed, and no binding to an atypical E box in the c-Kit promoter was detected. The relevance of these observations to the control of melanocyte-specific gene expression was highlighted by the fact that the E-box elements located in thetyrosinase, TRP-1, TRP-2, andQNR-71 promoters without exception possess a 5′ flanking T residue which is entirely conserved between species as diverse as man and turtle. The ability of Mi to discriminate between different E-box motifs provides a mechanism to restrict the repertoire of genes which are likely to be regulated by Mi and provides insight into the ability of bHLH-LZ transcription factors to achieve the specificity required for the precise coordination of transcription during development.


2005 ◽  
Vol 83 (4) ◽  
pp. 535-547 ◽  
Author(s):  
Gareth N Corry ◽  
D Alan Underhill

To date, the majority of the research regarding eukaryotic transcription factors has focused on characterizing their function primarily through in vitro methods. These studies have revealed that transcription factors are essentially modular structures, containing separate regions that participate in such activities as DNA binding, protein–protein interaction, and transcriptional activation or repression. To fully comprehend the behavior of a given transcription factor, however, these domains must be analyzed in the context of the entire protein, and in certain cases the context of a multiprotein complex. Furthermore, it must be appreciated that transcription factors function in the nucleus, where they must contend with a variety of factors, including the nuclear architecture, chromatin domains, chromosome territories, and cell-cycle-associated processes. Recent examinations of transcription factors in the nucleus have clarified the behavior of these proteins in vivo and have increased our understanding of how gene expression is regulated in eukaryotes. Here, we review the current knowledge regarding sequence-specific transcription factor compartmentalization within the nucleus and discuss its impact on the regulation of such processes as activation or repression of gene expression and interaction with coregulatory factors.Key words: transcription, subnuclear localization, chromatin, gene expression, nuclear architecture.


Oncogenesis ◽  
2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Xin Huang ◽  
Yichao Hou ◽  
Xiaoling Weng ◽  
Wenjing Pang ◽  
Lidan Hou ◽  
...  

AbstractExploring novel anticancer drugs to optimize the efficacy may provide a benefit for the treatment of colorectal cancer (CRC). Disulfiram (DSF), as an antialcoholism drug, is metabolized into diethyldithiocarbamate-copper complex (CuET) in vivo, which has been reported to exert the anticancer effects on various tumors in preclinical studies. However, little is known about whether CuET plays an anti-cancer role in CRC. In this study, we found that CuET had a marked effect on suppressing CRC progression both in vitro and in vivo by reducing glucose metabolism. Mechanistically, using RNA-seq analysis, we identified ALDH1A3 as a target gene of CuET, which promoted cell viability and the capacity of clonal formation and inhibited apoptosis in CRC cells. MicroRNA (miR)-16-5p and 15b-5p were shown to synergistically regulate ALDH1A3, which was negatively correlated with both of them and inversely correlated with the survival of CRC patients. Notably, using co-immunoprecipitation followed with mass spectrometry assays, we identified PKM2 as a direct downstream effector of ALDH1A3 that stabilized PKM2 by reducing ubiquitination. Taken together, we disclose that CuET treatment plays an active role in inhibiting CRC progression via miR-16-5p and 15b-5p/ALDH1A3/PKM2 axis–mediated aerobic glycolysis pathway.


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