Role of the basic helix-loop-helix protein ITF2 in the hormonal regulation of Sertoli cell differentiation

Abstract Inhibitor of DNA binding (Id) proteins function as inhibitors of members of the basic helix-loop-helix family of transcription factors and have been demonstrated to play an important role in regulating lymphopoiesis. However, the role of these proteins in regulation of myelopoiesis is currently unclear. In this study, we have investigated the role of Id1 and Id2 in the regulation of granulopoiesis. Id1 expression was initially up-regulated during early granulopoiesis, which was then followed by a decrease in expression during final maturation. In contrast, Id2 expression was up-regulated in terminally differentiated granulocytes. In order to determine whether Id expression plays a critical role in regulating granulopoiesis, Id1 and Id2 were ectopically expressed in CD34+ cells by retroviral transduction. Our experiments demonstrate that constitutive expression of Id1 inhibits eosinophil development, whereas in contrast neutrophil differentiation was modestly enhanced. Constitutive Id2 expression accelerates final maturation of both eosinophils and neutrophils, whereas inhibition of Id2 expression blocks differentiation of both lineages. Transplantation of β2-microglobulin-/- nonobese diabetic severe combined immunodeficient (NOD/SCID) mice with CD34+ cells ectopically expressing Id1 resulted in enhanced neutrophil development, whereas ectopic expression of Id2 induced both eosinophil and neutrophil development. These data demonstrate that both Id1 and Id2 play a critical, although differential role in granulopoiesis.

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An Examination of the Role of Transcriptional and Posttranscriptional Regulation in Rhabdomyosarcoma

Stem Cells International ◽

10.1155/2017/2480375 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Alexander J. Hron ◽

Atsushi Asakura

Keyword(s):

Skeletal Muscle ◽

Soft Tissue ◽

Posttranscriptional Regulation ◽

Progenitor Cell ◽

Treatment Options ◽

Soft Tissue Tumors ◽

Basic Helix Loop Helix ◽

Helix Loop Helix ◽

Bhlh Proteins

Rhabdomyosarcoma (RMS) is an aggressive family of soft tissue tumors that most commonly manifests in children. RMS variants express several skeletal muscle markers, suggesting myogenic stem or progenitor cell origin of RMS. In this review, the roles of both recently identified and well-established microRNAs in RMS are discussed and summarized in a succinct, tabulated format. Additionally, the subtypes of RMS are reviewed along with the involvement of basic helix-loop-helix (bHLH) proteins, Pax proteins, and microRNAs in normal and pathologic myogenesis. Finally, the current and potential future treatment options for RMS are outlined.

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The homeodomain-containing gene Xdbx inhibits neuronal differentiation in the developing embryo

Development ◽

10.1242/dev.127.13.2945 ◽

2000 ◽

Vol 127 (13) ◽

pp. 2945-2954 ◽

Cited By ~ 1

Author(s):

A.A. Gershon ◽

J. Rudnick ◽

L. Kalam ◽

K. Zimmerman

Keyword(s):

Neuronal Differentiation ◽

Normal Development ◽

Early Embryo ◽

Neural Plate ◽

Neural Progenitors ◽

Expression Domain ◽

Basic Helix Loop Helix ◽

Helix Loop Helix ◽

Early Neurogenesis

The development of the vertebrate nervous system depends upon striking a balance between differentiating neurons and neural progenitors in the early embryo. Our findings suggest that the homeodomain-containing gene Xdbx regulates this balance by maintaining neural progenitor populations within specific regions of the neuroectoderm. In posterior regions of the Xenopus embryo, Xdbx is expressed in a bilaterally symmetric stripe that lies at the middle of the mediolateral axis of the neural plate. This stripe of Xdbx expression overlaps the expression domain of the proneural basic/helix-loop-helix-containing gene, Xash3, and is juxtaposed to the expression domains of Xenopus Neurogenin related 1 and N-tubulin, markers of early neurogenesis in the embryo. Xdbx overexpression inhibits neuronal differentiation in the embryo and when co-injected with Xash3, Xdbx inhibits the ability of Xash3 to induce ectopic neurogenesis. One role of Xdbx during normal development may therefore be to restrict spatially neuronal differentiation within the neural plate, possibly by altering the neuronal differentiation function of Xash3.

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Opposing effects of the basic helix-loop-helix transcription factor SCL on erythroid and monocytic differentiation

Blood ◽

10.1182/blood.v87.1.102.102 ◽

1996 ◽

Vol 87 (1) ◽

pp. 102-111 ◽

Cited By ~ 59

Author(s):

T Hoang ◽

E Paradis ◽

G Brady ◽

F Billia ◽

K Nakahara ◽

...

Keyword(s):

Aminolevulinic Acid ◽

Single Cells ◽

Hematopoietic Cells ◽

Erythroid Differentiation ◽

Mrna Levels ◽

Monocytic Differentiation ◽

Basic Helix Loop Helix ◽

Helix Loop Helix ◽

Opposing Effects

Abstract The SCL gene (also called Tal-1 or TCL5) was identified because of its association with chromosomal translocations in childhood T-cell lymphoid leukemias. SCL codes for a basic helix-loop-helix (bHLH) factor that can function as a transcriptional activator or repressor. In the adult, SCL expression is restricted to hematopoietic cells and tissues, but its function in the process of lineage commitment is unknown. The present study was designed to address the role of SCL in hematopoietic cell differentiation. SCL expression was determined in primary hematopoietic cells through the screening of cDNA samples obtained by reverse transcription-polymerase chain reaction (RT-PCR) from single cells at different stages of differentiation. SCL RNA expression was highest in bipotential and committed erythroid precursors and diminished with subsequent maturation to proerythroblasts and normoblasts. In contrast, SCL mRNA was low to undetectable in precursors of granulocytes and monocytes and their maturing progeny. The same pattern of expression was observed after erythroid or monocytic differentiation of a bipotent cell line, TF-1, in that SCL mRNA levels remained elevated during erythroid differentiation and were downregulated with monocytic differentiation. Accordingly, TF-1 was chosen as a model to investigate the functional significance of this divergent pattern of SCL expression in the two lineages. Four independent clones stably transfected with an SCL expression vector exhibited enhanced spontaneous and delta-aminolevulinic acid-induced erythroid differentiation as measured by glycophorin expression and hemoglobinization, consistent with the view that SCL is a positive regulator of erythroid differentiation. Furthermore, constitutive SCL expression interfered with monocytic differentiation, as assessed by the generation of adherent cells and the expression of Fc gamma RII in response to TPA. These results suggest that the downregulation of SCL may be required for monocytic differentiation.

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Retraction Note: Impact of high-fat feeding on basic helix–loop–helix transcription factors controlling enteroendocrine cell differentiation

International Journal of Obesity ◽

10.1038/ijo.2016.118 ◽

2016 ◽

Vol 40 (9) ◽

pp. 1468-1468

Author(s):

Y Sakar ◽

F A Duca ◽

B Langelier ◽

F Devime ◽

H Blottiere ◽

...

Keyword(s):

Transcription Factors ◽

Cell Differentiation ◽

High Fat ◽

Enteroendocrine Cell ◽

Basic Helix Loop Helix ◽

Helix Loop Helix ◽

Fat Feeding

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Role of mammalian Y chromosome in sex determination

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1988.0114 ◽

1988 ◽

Vol 322 (1208) ◽

pp. 63-72 ◽

Cited By ~ 34

Keyword(s):

Cell Differentiation ◽

Sex Determination ◽

Y Chromosome ◽

Sertoli Cell ◽

Sertoli Cells ◽

Sex Reversal ◽

Testicular Development ◽

Chimeric Mouse ◽

Embryonic Gonad

It has long been assumed that the mammalian Y chromosome either encodes, or controls the production of, a diffusible testis-determining molecule, exposure of the embryonic gonad to this molecule being all that is required to divert it along the testicular pathway. My recent finding that Sertoli cells in XX ↔ XY chimeric mouse testes are exclusively XY has led me to propose a new model in which the Y acts cell-autonomously to bring about Sertoli-cell differentiation. I have suggested that all other aspects of foetal testicular development are triggered by the Sertoli cells without further Y-chromosome involvement. This model thus equates mammalian sex determination with Sertoli-cell determination. Examples of natural and experimentally induced sex reversal are discussed in the context of this model.

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