Ras signaling and its effector RREB1 are required for the dissociation of MEE cells in palatogenesis

Cleft palate is one of the major congenital craniofacial birth defects. The etiology underlying the pathogenesis of cleft palate has largely remained unelucidated. Dissociation of the medial edge epithelium (MEE) at the contacting region of palatal shelves and subsequent migration or apoptosis of MEE cells is required for the proper MEE removal. Ras Responsive Element Binding Protein 1 (RREB1), a RAS transcriptional effector, has recently been shown to play a crucial role in developmental EMT, in which loss of epithelial characteristics is an initial step, during mid-gastrulation of embryonic development. Interestingly, the involvement of RREB1 in cleft palate has been indicated in humans. Here, we demonstrated that pan-Ras inhibitor prevents the dissociation of MEE during palatal fusion. Rreb1 is expressed in the palatal epithelium during palatal fusion, and knockdown of Rreb1 in palatal organ culture resulted in palatal fusion defects by inhibiting the dissociation of MEE cells. Our present findings provide evidence that RREB1-mediated Ras signaling is required during palatal fusion. Aberrant RREB1-mediated Ras signaling might be involved in the pathogenesis of cleft palate.

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Pathogenesis of cleft palate in TGF-beta3 knockout mice

Development ◽

10.1242/dev.126.17.3869 ◽

1999 ◽

Vol 126 (17) ◽

pp. 3869-3879 ◽

Cited By ~ 3

Author(s):

Y. Taya ◽

S. O'Kane ◽

M.W. Ferguson

Keyword(s):

Organ Culture ◽

Cleft Palate ◽

Transforming Growth Factor ◽

Outer Cell ◽

Complete Disappearance ◽

Surface Receptors ◽

Palatal Fusion ◽

Medial Edge

We previously reported that mutation of the transforming growth factor-beta3 (TGF-beta3) gene caused cleft palate in homozygous null (−/−) mice. TGF-beta3 is normally expressed in the medial edge epithelial (MEE) cells of the palatal shelf. In the present study, we investigated the mechanisms by which TGF-beta3 deletions caused cleft palate in 129 × CF-1 mice. For organ culture, palatal shelves were dissected from embryonic day 13.5 (E13.5) mouse embryos. Palatal shelves were placed singly or in pairs on Millipore filters and cultured in DMEM/F12 medium. Shelves were placed in homologous (+/+ vs +/+, −/− vs −/−, +/− vs +/−) or heterologous (+/+ vs −/−, +/− vs −/−, +/+ vs +/−) paired combinations and examined by macroscopy and histology. Pairs of −/− and −/− shelves failed to fuse over 72 hours of culture whereas pairs of +/+ (wild-type) and +/+ or +/− (heterozygote) and +/−, as well as +/+ and −/− shelves, fused within the first 48 hour period. Histological examination of the fused +/+ and +/+ shelves showed complete disappearance of the midline epithelial seam whereas −/− and +/+ shelves still had some seam remnants. In order to investigate the ability of TGF-beta family members to rescue the fusion between −/− and −/− palatal shelves in vitro, either recombinant human (rh) TGF-beta1, porcine (p) TGF-beta2, rh TGF-beta3, rh activin, or p inhibin was added to the medium in different concentrations at specific times and for various periods during the culture. In untreated organ culture −/− palate pairs completely failed to fuse, treatment with TGF-beta3 induced complete palatal fusion, TGF-beta1 or TGF-beta2 near normal fusion, but activin and inhibin had no effect. We investigated ultrastructural features of the surface of the MEE cells using SEM to compare TGF-beta3-null embryos (E 12. 5-E 16.5) with +/+ and +/− embryos in vivo and in vitro. Up to E13.5 and after E15.5, structures resembling short rods were observed in both +/+ and −/− embryos. Just before fusion, at E14.5, a lot of filopodia-like structures appeared on the surface of the MEE cells in +/+ embryos, however, none were observed in −/− embryos, either in vivo or in vitro. With TEM these filopodia are coated with material resembling proteoglycan. Interestingly, addition of TGF-beta3 to the culture medium which caused fusion between the −/− palatal shelves also induced the appearance of these filopodia on their MEE surfaces. TGF-beta1 and TGF-beta2 also induced filopodia on the −/− MEE but to a lesser extent than TGF-beta3 and additionally induced lamellipodia on their cell surfaces. These results suggest that TGF-beta3 may regulate palatal fusion by inducing filopodia on the outer cell membrane of the palatal medial edge epithelia prior to shelf contact. Exogenous recombinant TGF-beta3 can rescue fusion in −/− palatal shelves by inducing such filopodia, illustrating that the effects of TGF-beta3 are transduced by cell surface receptors which raises interesting potential therapeutic strategies to prevent and treat embryonic cleft palate.

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The transcription factor Rreb1 regulates epithelial architecture and invasiveness in gastrulating mouse embryos

10.1101/2020.11.12.379578 ◽

2020 ◽

Author(s):

Sophie M. Morgani ◽

Jie Su ◽

Jennifer Nichols ◽

Joan Massagué ◽

Anna-Katerina Hadjantonakis

Keyword(s):

Transcription Factor ◽

Ras Signaling ◽

Zinc Finger Transcription Factor ◽

Cell Behaviors ◽

Disease States ◽

Element Binding Protein ◽

Cardiovascular Defects ◽

Responsive Element ◽

Mutant Cells ◽

Shed Light

AbstractRas-responsive element-binding protein 1 (Rreb1) is a zinc-finger transcription factor downstream of RAS signaling. Rreb1 has been implicated in cancer but little is known about its role in mammalian non-disease states. Here, we found that Rreb1 is essential for mouse embryonic development. Loss of Rreb1 led to a reduction in the expression of vasculogenesis factors, cardiovascular defects and embryonic lethality. During gastrulation, the absence of Rreb1 also resulted in the upregulation of cytoskeleton-associated genes, a change in the organization of F-ACTIN and adherens junctions within the pluripotent epiblast, and perturbed epithelial architecture characterized by irregular tissue folding and abnormal accumulations of cells. Moreover, Rreb1 mutant cells ectopically exited the epiblast epithelium through the underlying basement membrane, paralleling cell behaviors observed during metastasis. Thus, disentangling the function of Rreb1 in development could shed light on its role in cancer and other diseases involving loss of epithelial integrity.

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Far Upstream Element Binding Protein Plays a Crucial Role in Embryonic Development, Hematopoiesis, and Stabilizing Myc Expression Levels

American Journal Of Pathology ◽

10.1016/j.ajpath.2015.10.028 ◽

2016 ◽

Vol 186 (3) ◽

pp. 701-715 ◽

Cited By ~ 17

Author(s):

Weixin Zhou ◽

Yang Jo Chung ◽

Edgardo R. Parrilla Castellar ◽

Ying Zheng ◽

Hye-Jung Chung ◽

...

Keyword(s):

Embryonic Development ◽

Crucial Role ◽

Binding Protein ◽

Expression Levels ◽

Element Binding Protein ◽

Upstream Element

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The transcription factor Rreb1 regulates epithelial architecture, invasiveness and vasculogenesis in early mouse embryos

eLife ◽

10.7554/elife.64811 ◽

2021 ◽

Vol 10 ◽

Author(s):

Sophie M Morgani ◽

Jie Su ◽

Jennifer Nichols ◽

Joan Massagué ◽

Anna-Katerina Hadjantonakis

Keyword(s):

Transcription Factor ◽

Ras Signaling ◽

Cell Behaviors ◽

Disease States ◽

Element Binding Protein ◽

Cardiovascular Defects ◽

Early Mouse ◽

Responsive Element ◽

Mutant Cells ◽

Shed Light

Ras-responsive element-binding protein 1 (Rreb1) is a zinc-finger transcription factor acting downstream of RAS signaling. Rreb1 has been implicated in cancer and Noonan-like RASopathies. However, little is known about its role in mammalian non-disease states. Here, we show that Rreb1 is essential for mouse embryonic development. Loss of Rreb1 led to a reduction in the expression of vasculogenic factors, cardiovascular defects and embryonic lethality. During gastrulation, the absence of Rreb1 also resulted in the upregulation of cytoskeleton-associated genes, a change in the organization of F-ACTIN and adherens junctions within the pluripotent epiblast, and perturbed epithelial architecture. Moreover, Rreb1 mutant cells ectopically exited the epiblast epithelium through the underlying basement membrane, paralleling cell behaviors observed during metastasis. Thus, disentangling the function of Rreb1 in development should shed light on its role in cancer and other diseases involving loss of epithelial integrity.

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Crucial role for Ser133-phosphorylated form of cyclic AMP-responsive element binding protein signaling in the differentiation and survival of neural progenitors under chronic cerebral hypoperfusion

Neuroscience ◽

10.1016/j.neuroscience.2009.05.004 ◽

2009 ◽

Vol 162 (2) ◽

pp. 525-536 ◽

Cited By ~ 23

Author(s):

N. Miyamoto ◽

R. Tanaka ◽

N. Zhang ◽

H. Shimura ◽

M. Onodera ◽

...

Keyword(s):

Cyclic Amp ◽

Crucial Role ◽

Binding Protein ◽

Neural Progenitors ◽

Chronic Cerebral Hypoperfusion ◽

Cerebral Hypoperfusion ◽

Protein Signaling ◽

Phosphorylated Form ◽

Element Binding Protein ◽

Responsive Element

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Cleavage of cyclic AMP-responsive element-binding protein H aggravates myocardial hypoxia reperfusion injury in a hepatocyte–myocardial cell co-culture system

Journal of International Medical Research ◽

10.1177/0300060520904835 ◽

2020 ◽

Vol 48 (5) ◽

pp. 030006052090483

Author(s):

Zehao Jin ◽

Ye Chen ◽

Xiaochun Weng ◽

Anwu Huang ◽

Shuang Lin ◽

...

Keyword(s):

Cyclic Amp ◽

Myocardial Ischemia ◽

Reperfusion Injury ◽

Acute Phase ◽

Proinflammatory Cytokines ◽

Acute Phase Response ◽

Culture System ◽

Element Binding Protein ◽

Myocardial Hypoxia ◽

Responsive Element

Objective This study aimed to determine whether proinflammatory cytokines have an effect on myocardial cells (MCs) and hepatocytes during myocardial ischemia to induce cyclic AMP-responsive element-binding protein H (CREBH) cleavage, activate the acute phase response in the liver, and cause a superimposed injury in MCs. Methods In this study, a hepatocyte–MC transwell co-culture system was used to investigate the relationship between myocardial hypoxia/reperfusion injury and CREBH cleavage. MCs and hepatocytes of neonatal rats were obtained from the ventricles and livers of Sprague–Dawley rats, respectively. MCs were inoculated into the lower chamber of transwell chambers for 12 hours under hypoxia. Levels of the endoplasmic reticulum stress protein glucose-regulated protein 78 in MCs, CREBH in hepatocytes, inflammatory factor (tumor necrosis factor-α and interleukin-6) levels, and cell viability were evaluated. The effect of CREBH knockdown was also studied using a CREBH-specific short hairpin RNA (Ad-CREBHi). Results We found that proinflammatory cytokines affect MCs and hepatocytes during myocardial ischemia to induce CREBH cleavage, activate the acute phase response in the liver, and cause superimposed injury in MCs. Conclusions Expression of CREBH aggravates myocardial injury during myocardial ischemia.

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Iron-responsive element-binding protein. Phosphorylation by protein kinase C.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)74258-6 ◽

1993 ◽

Vol 268 (36) ◽

pp. 27363-27370

Author(s):

R S Eisenstein ◽

P T Tuazon ◽

K L Schalinske ◽

S A Anderson ◽

J A Traugh

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Protein Phosphorylation ◽

Binding Protein ◽

Iron Responsive Element ◽

Kinase C ◽

Element Binding Protein ◽

Responsive Element

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Iron regulates the activity of the iron-responsive element binding protein without changing its rate of synthesis or degradation.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)35789-2 ◽

1992 ◽

Vol 267 (34) ◽

pp. 24466-24470 ◽

Cited By ~ 6

Author(s):

C.K. Tang ◽

J Chin ◽

J.B. Harford ◽

R.D. Klausner ◽

T.A. Rouault

Keyword(s):

Binding Protein ◽

Iron Responsive Element ◽

Element Binding Protein ◽

Responsive Element

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An IRP-like protein from Plasmodium falciparum binds to a mammalian iron-responsive element

Blood ◽

10.1182/blood.v98.8.2555 ◽

2001 ◽

Vol 98 (8) ◽

pp. 2555-2562 ◽

Cited By ~ 26

Author(s):

Mark Loyevsky ◽

Timothy LaVaute ◽

Charles R. Allerson ◽

Robert Stearman ◽

Olakunle O. Kassim ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Regulatory Protein ◽

Protein S ◽

Fold Increase ◽

Binding Activity ◽

Mobility Shift ◽

Iron Responsive Element ◽

Element Binding Protein ◽

Responsive Element ◽

Electrophoretic Mobility Shift Assays

Abstract This study cloned and sequenced the complementary DNA (cDNA) encoding of a putative malarial iron responsive element-binding protein (PfIRPa) and confirmed its identity to the previously identified iron-regulatory protein (IRP)–like cDNA from Plasmodium falciparum. Sequence alignment showed that the plasmodial sequence has 47% identity with human IRP1. Hemoglobin-free lysates obtained from erythrocyte-stage P falciparum contain a protein that binds a consensus mammalian iron-responsive element (IRE), indicating that a protein(s) with iron-regulatory activity was present in the lysates. IRE-binding activity was found to be iron regulated in the electrophoretic mobility shift assays. Western blot analysis showed a 2-fold increase in the level of PfIRPa in the desferrioxamine-treated cultures versus control or iron-supplemented cells. Malarial IRP was detected by anti-PfIRPa antibody in the IRE-protein complex fromP falciparum lysates. Immunofluorescence studies confirmed the presence of PfIRPa in the infected red blood cells. These findings demonstrate that erythrocyte P falciparum contains an iron-regulated IRP that binds a mammalian consensus IRE sequence, raising the possibility that the malaria parasite expresses transcripts that contain IREs and are iron-dependently regulated.

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