Serum response element associated transcription factors in mouse embryos: Serum response factor, YY1, and PEA3 factor

Growth factor regulation of c-fos proto-oncogene transcription is mediated by a 20-bp region of dyad symmetry, termed the serum response element. The inner core of this element binds a 67-kDa phosphoprotein, the serum response factor (SRF), that is thought to play a pivotal role in the c-fos transcriptional response. To investigate the mechanism by which SRF regulates c-fos expression, we generated polyclonal anti-SRF antibodies and used these antibodies to analyze the biochemical properties of SRF. These studies indicate that the synthesis of SRF is transient, occurring within 30 min to 4 h after serum stimulation of quiescent fibroblasts. Newly synthesized SRF is transported to the nucleus, where it is increasingly modified by phosphorylation during progression through the cell cycle. Within 2 h of serum stimulation, differentially modified forms of SRF can be distinguished on the basis of the ability to bind a synthetic serum response element. SRF protein exhibits a half-life of greater than 12 h and is predominantly nuclear, with no change occurring in its localization upon serum stimulation. We find that the induction of SRF synthesis is regulated at the transcriptional level and that cytoplasmic SRF mRNA is transiently expressed with somewhat delayed kinetics compared with c-fos mRNA expression. These features of SRF expression suggest a model whereby newly synthesized SRF functions in the shutoff of c-fos transcription.

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Structural and dynamic changes of the serum response element and the core domain of serum response factor induced by their association

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2009.11.032 ◽

2010 ◽

Vol 391 (1) ◽

pp. 203-208 ◽

Cited By ~ 6

Author(s):

Josef Štěpánek ◽

Vladimír Kopecký ◽

Alberto Mezzetti ◽

Pierre-Yves Turpin ◽

Denise Paulin ◽

...

Keyword(s):

Serum Response Factor ◽

Response Factor ◽

Serum Response Element ◽

Dynamic Changes ◽

Response Element ◽

Core Domain ◽

The Core ◽

Serum Response

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YY1 facilitates the association of serum response factor with the c-fos serum response element.

Molecular and Cellular Biology ◽

10.1128/mcb.15.11.5975 ◽

1995 ◽

Vol 15 (11) ◽

pp. 5975-5982 ◽

Cited By ~ 57

Author(s):

S Natesan ◽

M Gilman

Keyword(s):

Protein Interactions ◽

Structural Changes ◽

Serum Response Factor ◽

Response Factor ◽

Protein Protein Interactions ◽

Serum Response Element ◽

Response Element ◽

General Role ◽

A Site ◽

Serum Response

YY1 is a multifunctional transcription factor that acts as an activator or repressor in different contexts. YY1 binds to multiple sites in the mouse c-fos promoter, inducing at each site a sharp DNA bend. Binding of YY1 to a site situated between the cyclic AMP response element (CRE) and the TATA box bends the DNA in a way that interferes with the interaction of proteins bound at the CRE and TATA elements, resulting in repression of transcription. Here, we show that binding of YY1 to a different site in the c-fos promoter has a different result. Binding of YY1 to the c-fos serum response element (SRE) enhances the binding of serum response factor (SRF). This enhancement requires the binding of YY1 to SRE DNA. YY1 and SRF can cooccupy the SRE at least transiently. In the region of overlapping contact, YY1 contacts DNA in the major groove, while SRF contacts DNA in the minor groove. YY1 also enhances the association of SRF with the SRE in transfected insect cells. Thus, although YY1 induces similar structural changes in DNA at different binding sites, it can have distinct local effects on protein-DNA and protein-protein interactions. These data support a general role for YY1 in the building of highly organized promoter complexes.

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Mechanism of binding of serum response factor to serum response element

FEBS Journal ◽

10.1111/j.1742-4658.2005.04724.x ◽

2005 ◽

Vol 272 (12) ◽

pp. 3105-3119 ◽

Cited By ~ 6

Author(s):

Alexis Huet ◽

Ara Parlakian ◽

Marie-Claire Arnaud ◽

Jean-Marie Glandières ◽

Pierre Valat ◽

...

Keyword(s):

Serum Response Factor ◽

Response Factor ◽

Serum Response Element ◽

Response Element ◽

Serum Response

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Neurokinin B Induces c-fos Transcription via Protein Kinase C and Activation of Serum Response Factor and Elk-1 in Immortalized GnRH Neurons

Endocrinology ◽

10.1210/en.2014-1263 ◽

2014 ◽

Vol 155 (10) ◽

pp. 3909-3919 ◽

Cited By ~ 7

Author(s):

Christine A. Glidewell-Kenney ◽

Crystal Trang ◽

Paul P. Shao ◽

Navarre Gutierrez-Reed ◽

Adaku M. Uzo-Okereke ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Serum Response Factor ◽

Response Factor ◽

Gnrh Neuron ◽

Serum Response Element ◽

Neurokinin B ◽

Response Element ◽

Kinase C ◽

Serum Response

Abstract Mutations in neurokinin B (NKB) and its receptor, NK3R, were identified in human patients with hypogonadotropic hypogonadism, a disorder characterized by lack of puberty and infertility. Further studies have suggested that NKB acts at the level of the hypothalamus to control GnRH neuron activity, either directly or indirectly. We recently reported that treatment with senktide, a NK3R agonist, induced GnRH secretion and expression of c-fos mRNA in GT1-7 cells. Here, we map the responsive region in the murine c-fos promoter to between −400 and −200 bp, identify the signal transducer and activator of transcription (STAT) (−345) and serum response element (−310) sites as required for induction, a modulatory role for the Ets site (−318), and show that induction is protein kinase C dependent. Using gel shift and Gal4 assays, we further show that phosphorylation of Elk-1 leads to binding to DNA in complex with serum response factor at serum response element and Ets sites within the c-fos promoter. Thus, we determine molecular mechanisms involved in NKB regulation of c-fos induction, which may play a role in modulation of GnRH neuron activation.

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Characterization of SAP-1, a protein recruited by serum response factor to the c-fos serum response element

Cell ◽

10.1016/0092-8674(92)90194-h ◽

1992 ◽

Vol 68 (3) ◽

pp. 597-612 ◽

Cited By ~ 312

Author(s):

Stephen Dalton ◽

Richard Treisman

Keyword(s):

Serum Response Factor ◽

Response Factor ◽

Serum Response Element ◽

Response Element ◽

Serum Response

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A growth factor-induced kinase phosphorylates the serum response factor at a site that regulates its DNA-binding activity.

Molecular and Cellular Biology ◽

10.1128/mcb.13.10.6260 ◽

1993 ◽

Vol 13 (10) ◽

pp. 6260-6273 ◽

Cited By ~ 176

Author(s):

V M Rivera ◽

C K Miranti ◽

R P Misra ◽

D D Ginty ◽

R H Chen ◽

...

Keyword(s):

Growth Factor ◽

Serum Response Factor ◽

Critical Role ◽

Response Factor ◽

Serum Response Element ◽

Response Element ◽

Ribosomal S6 Kinase ◽

Serum Response

A signaling pathway by which growth factors may induce transcription of the c-fos proto-oncogene has been characterized. Growth factor stimulation of quiescent fibroblasts activates a protein kinase cascade that leads to the rapid and transient phosphorylation of the serum response factor (SRF), a regulator of c-fos transcription. The in vivo kinetics of SRF phosphorylation and dephosphorylation parallel the activation and subsequent repression of c-fos transcription, suggesting that this phosphorylation event plays a critical role in the control of c-fos expression. The ribosomal S6 kinase pp90rsk, a growth factor-inducible kinase, phosphorylates SRF in vitro at serine 103, the site that becomes newly phosphorylated upon growth factor stimulation in vivo. Phosphorylation of serine 103 significantly enhances the affinity and rate with which SRF associates with its binding site, the serum response element, within the c-fos promoter. These results suggest a model in which the growth factor-induced phosphorylation of SRF at serine 103 contributes to the activation of c-fos transcription by facilitating the formation of an active transcription complex at the serum response element.

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Net-b, a Ras-insensitive factor that forms ternary complexes with serum response factor on the serum response element of the fos promoter.

Molecular and Cellular Biology ◽

10.1128/mcb.17.10.5667 ◽

1997 ◽

Vol 17 (10) ◽

pp. 5667-5678 ◽

Cited By ~ 18

Author(s):

A Giovane ◽

P Sobieszczuk ◽

A Ayadi ◽

S M Maira ◽

B Wasylyk

Keyword(s):

Ternary Complex ◽

Serum Response Factor ◽

Splice Variants ◽

Ternary Complexes ◽

Response Factor ◽

Serum Response Element ◽

Response Element ◽

Serum Response ◽

Ras Signalling ◽

Low Serum

The Ras signalling pathway targets transcription factors such as the ternary complex factors that are recruited by the serum response factor to form complexes on the serum response element (SRE) of the fos promoter. We have identified a new ternary complex factor, Net-b. We report the features of the net gene and show that it produces several splice variants, net-b and net-c. net-b RNA and protein are expressed in a variety of tissues and cell lines. net-c RNA is expressed at low levels, and the protein was not detected, raising the possibility that it is a cryptic splice variant. We have studied the composition of ternary complexes that form on the SRE of the fos promoter with extracts from fibroblasts (NIH 3T3) cultured under various conditions and pre-B cells (70Z/3) before and after differentiation with lipopolysaccharide (LPS). The fibroblast complexes contain mainly Net-b followed by Sap1 and Elk1. Net-b complexes, as well as Sap1 and Elk1, are induced by epidermal growth factor (EGF) stimulation of cells cultured in low serum. Pre-B-cell complexes contain mainly Sap1, with less of Net-b and little of Elk1. There is little change upon LPS-induced differentiation compared to the increase with EGF in fibroblasts. We have also found that Net-b is a nuclear protein that constitutively represses transcription. Net-b is not activated by Ras signalling, in contrast to Net, Sap1a, and Elk1. We have previously reported that down-regulation of Net proteins with antisense RNA increases SRE activity. The increase in SRE activity is observed at low serum levels and is even greater after serum stimulation, showing that the SRE is under negative regulation by Net proteins and the level of repression increases during induction. Net-b, the predominant factor in ternary complexes in fibroblasts, may both keep the activity of the SRE low in the absence of strong inducing conditions and rapidly shut the activity off after stimulation.

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