Growth Differentiation Factor-9 Signaling Is Mediated by the Type I Receptor, Activin Receptor-Like Kinase 5

Growth differentiation factor-8 (GDF-8) has been recently shown to be expressed in human granulosa cells, and the mature form of GDF-8 protein can be detected in the follicular fluid. However, the biological function and significance of this growth factor in the human ovary remains to be determined. Here, we investigated the effects of GDF-8 on steroidogenic enzyme expression and the potential mechanisms of action in luteinized human granulosa cells. We demonstrated that treatment with GDF-8 did not affect the mRNA levels of P450 side-chain cleavage enzyme and 3β-hydroxysteroid dehydrogenase, whereas it significantly down-regulated steroidogenic acute regulatory protein (StAR) expression and decreased progesterone production. The suppressive effect of GDF-8 on StAR expression was abolished by the inhibition of the TGF-β type I receptor. In addition, treatment with GDF-8 activated both Smad2/3 and ERK1/2 signaling pathways. Furthermore, knockdown of activin receptor-like kinase 5 reversed the effects of GDF-8 on Smad2/3 phosphorylation and StAR expression. The inhibition of Smad3 or ERK1/2 signaling pathways attenuated the GDF-8-induced down-regulation of StAR and production of progesterone. Interestingly, the concentrations of GDF-8 were negatively correlated with those of progesterone in human follicular fluid. These results indicate a novel autocrine function of GDF-8 to down-regulate StAR expression and decrease progesterone production in luteinized human granulosa cells, most likely through activin receptor-like kinase 5-mediated Smad3 and ERK1/2 signaling pathways. Our findings suggest that granulosa cells might play a critical role in the regulation of progesterone production to prevent premature luteinization during the final stage of folliculogenesis.

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Activin receptor-like kinase-2 inhibits activin signaling by blocking the binding of activin to its type II receptor

Journal of Endocrinology ◽

10.1677/joe-07-0281 ◽

2007 ◽

Vol 195 (1) ◽

pp. 95-103 ◽

Cited By ~ 19

Author(s):

Nina Renlund ◽

Francis H O’Neill ◽

LiHua Zhang ◽

Yisrael Sidis ◽

Jose Teixeira

Keyword(s):

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Underlying Mechanism ◽

Luciferase Reporter ◽

Type I ◽

Type Ii ◽

Activin Receptor ◽

Activin Signaling ◽

Endogenous Expression ◽

Receptor Like Kinase

Activin receptor-like kinase-2 (Alk2) has been shown to be a promiscuous type I receptor for the transforming growth factor β (TGFβ) family of growth and differentiation factors, such as activin, bone morphogenetic proteins, and Müllerian inhibiting substance (MIS). We have studied the putative role of Alk2 in activin signaling using MA-10 cells, a mouse transformed Leydig cell line, in which endogenous expression of cytochrome P450 c17 hydroxylase/C17–20 lyase mRNA is inhibited by both MIS and activin A. Overexpression of Alk2 in MA-10 cells inhibited the activation of the activin-responsive CAGA-luciferase reporter and, conversely, transfection of siRNA for Alk2 increased the response. In contrast, overexpression of the MIS type II receptor in MA-10 cells increased the activin-mediated induction of CAGA-luciferase approximately fivefold, which we hypothesized occurs by MIS type II receptor sequestering endogenous Alk2. Binding experiments with 125I-labeled activin show that the underlying mechanism of Alk2-mediated inhibition of activin signaling involves Alk2 blocking the access of activin to its type II receptor, which we show can bind Alk2 in the absence of ligand. These results show that the complement of other type I receptors in addition to the ligand-specific type I receptor can provide an important mechanism for modulating cell-specific responses to members of the TGFβ family.

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The Expression of Activin Receptor-Like Kinase 1 (ACVRL1/ALK1) in Hippocampal Arterioles Declines During Progression of Alzheimer’s Disease

Cerebral Cortex Communications ◽

10.1093/texcom/tgaa031 ◽

2020 ◽

Vol 1 (1) ◽

Author(s):

Kelley E Anderson ◽

Thomas A Bellio ◽

Emily Aniskovich ◽

Stephanie L Adams ◽

Jan Krzysztof Blusztajn ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Blood Vessels ◽

Pyramidal Neurons ◽

Brain Parenchyma ◽

Amyloid Angiopathy ◽

Type I ◽

Clinical Dementia Rating ◽

Activin Receptor ◽

Receptor Like Kinase

Abstract Cerebral amyloid angiopathy (CAA) in Alzheimer’s disease (AD)—deposition of beta amyloid (Aβ) within the walls of cerebral blood vessels—typically accompanies Aβ buildup in brain parenchyma and causes abnormalities in vessel structure and function. We recently demonstrated that the immunoreactivity of activin receptor-like kinase 1 (ALK1), the type I receptor for circulating BMP9/BMP10 (bone morphogenetic protein) signaling proteins, is reduced in advanced, but not early stages of AD in CA3 pyramidal neurons. Here we characterize vascular expression of ALK1 in the context of progressive AD pathology accompanied by amyloid angiopathy in postmortem hippocampi using immunohistochemical methods. Hippocampal arteriolar wall ALK1 signal intensity was 35% lower in AD patients (Braak and Braak Stages IV and V [BBIV-V]; clinical dementia rating [CDR1-2]) as compared with subjects with early AD pathologic changes but either cognitively intact or with minimal cognitive impairment (BBIII; CDR0-0.5). The intensity of Aβ signal in arteriolar walls was similar in all analyzed cases. These data suggest that, as demonstrated previously for specific neuronal populations, ALK1 expression in blood vessels is also vulnerable to the AD pathophysiologic process, perhaps related to CAA. However, cortical arterioles may remain responsive to the ALK1 ligands, such as BMP9 and BMP10 in early and moderate AD.

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Targeting tumour vasculature by inhibiting activin receptor-like kinase (ALK)1 function

Biochemical Society Transactions ◽

10.1042/bst20160093 ◽

2016 ◽

Vol 44 (4) ◽

pp. 1142-1149 ◽

Cited By ~ 23

Author(s):

Amaya García de Vinuesa ◽

Matteo Bocci ◽

Kristian Pietras ◽

Peter ten Dijke

Keyword(s):

Growth Factor ◽

Transforming Growth Factor Beta ◽

Transforming Growth Factor ◽

New Combination ◽

Current Status ◽

Human Antibody ◽

Type I ◽

Activin Receptor ◽

Alternative Pathways ◽

Receptor Like Kinase

Angiogenesis is a hallmark of cancer and is now a validated therapeutic target in the clinical setting. Despite the initial success, anti-angiogenic compounds impinging on the vascular endothelial growth factor (VEGF) pathway display limited survival benefits in patients and resistance often develops due to activation of alternative pathways. Thus, finding and validating new targets is highly warranted. Activin receptor-like kinase (ALK)1 is a transforming growth factor beta (TGF-β) type I receptor predominantly expressed in actively proliferating endothelial cells (ECs). ALK1 has been shown to play a pivotal role in regulating angiogenesis by binding to bone morphogenetic protein (BMP)9 and 10. Two main pharmacological inhibitors, an ALK1-Fc fusion protein (Dalantercept/ACE-041) and a fully human antibody against the extracellular domain of ALK1 (PF-03446962) are currently under clinical development. Herein, we briefly recapitulate the role of ALK1 in blood vessel formation and the current status of the preclinical and clinical studies on inhibition of ALK1 signalling as an anti-angiogenic strategy. Future directions in terms of new combination regimens will also be presented.

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The activin receptor-like kinase 6 Booroola mutation enhances suppressive effects of bone morphogenetic protein 2 (BMP2), BMP4, BMP6 and growth and differentiation factor-9 on FSH release from ovine primary pituitary cell cultures

Journal of Endocrinology ◽

10.1677/joe-07-0148 ◽

2007 ◽

Vol 196 (2) ◽

pp. 251-261 ◽

Cited By ~ 16

Author(s):

Julia M Young ◽

Jennifer L Juengel ◽

Kenneth G Dodds ◽

Mhairi Laird ◽

Peter K Dearden ◽

...

Keyword(s):

Cell Cultures ◽

Transforming Growth Factor ◽

Direct Action ◽

Pituitary Cell ◽

Bone Morphogenetic Protein 2 ◽

Pituitary Cells ◽

Activin Receptor ◽

Differentiation Factor ◽

Receptor Like Kinase

Bone morphogenetic proteins (BMPs) have been shown to influence the regulation of FSH synthesis and secretion at the level of the pituitary. Primary pituitary cells were harvested and cultured from Booroola ewes homozygous for a mutation in activin receptor-like kinase 6 (ALK6) also known as BMP receptor IB (BMPRIB), and from wild-type (WT) ewes to determine if the mutation caused alterations in FSH secretion in vitro. The cells were collected 24 h following induction of luteolysis and cultured for 72 h prior to being challenged for 24 h with BMP2, BMP4, BMP6, growth and differentiation factor-9 (GDF9), transforming growth factor-β 1, activin-A and GnRH. The levels of FSH and LH were measured by RIA and then compared with the untreated controls. Primary pituitary cell cultures from Booroola ewes secreted less FSH than WT cells in the presence of BMP2, BMP4 and BMP6. These BMPs did not affect the FSH stores within the cells, or the levels of LH released. GDF9 appeared to act in a BMP-like manner by suppressing FSH secretion. The ALK6 receptor however, was not found to co-localise with gonadotroph cells in either Booroola or WT pituitary tissues. These findings imply that the increased sensitivity of Booroola cells to BMP2, BMP4, BMP6 and GDF9 cannot be due to the direct action of the ALK6 mutant Booroola receptor in the cells that synthesise FSH.

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Transforming Growth Factor β (TGFβ) Signaling via Differential Activation of Activin Receptor-like Kinases 2 and 5 during Cardiac Development

Journal of Biological Chemistry ◽

10.1074/jbc.m209668200 ◽

2002 ◽

Vol 277 (51) ◽

pp. 50183-50189 ◽

Cited By ~ 11

Author(s):

Simone M. Ward ◽

Jay S. Desgrosellier ◽

Xiaoli Zhuang ◽

Joey V. Barnett ◽

Jonas B. Galper

Keyword(s):

Promoter Activity ◽

Transforming Growth Factor ◽

Cardiac Development ◽

Transforming Growth Factor Β ◽

Type I ◽

In Ovo ◽

Activin Receptor ◽

Atrial Cells ◽

Tgfβ Receptors ◽

Receptor Like Kinase

Little is known regarding factors that induce parasympathetic responsiveness during cardiac development. We demonstrated previously that in atrial cells cultured from chicks 14 daysin ovo, transforming growth factor β (TGFβ) decreased parasympathetic inhibition of beat rate by the muscarinic agonist, carbamylcholine, by 5-fold and decreased expression of Gαi2. Here in atrial cells 5 daysin ovo,TGFβ increased carbamylcholine inhibition of beat rate 2.5-fold and increased expression of Gαi2. TGFβ also stimulated Gαi2mRNA expression and promoter activity at day 5 while inhibiting them at day 14in ovo. Over the same time course expression of type I TGFβ receptors, chick activin receptor-like kinase 2 and 5 increased with a 2.3-fold higher increase in activin receptor-like kinase 2. Constitutively active activin receptor-like kinase 2 inhibited Gαi2promoter activity, whereas constitutively active activin receptor-like kinase 5 stimulated Gαi2promoter activity independent of embryonic age. In 5-day atrial cells, TGFβ stimulated the p3TP-lux reporter, which is downstream of activin receptor-like kinase 5 and had no effect on the activity of the pVent reporter, which is downstream of activin receptor-like kinase 2. In 14-day cells, TGFβ stimulated both pVent and p3TP-lux. Thus TGFβ exerts opposing effects on parasympathetic response and Gαi2expression by activating different type I TGFβ receptors at distinct stages during cardiac development.

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Role and Regulation of Nodal/Activin Receptor-Like Kinase 7 Signaling Pathway in the Control of Ovarian Follicular Atresia

Molecular Endocrinology ◽

10.1210/me.2005-0446 ◽

2006 ◽

Vol 20 (10) ◽

pp. 2469-2482 ◽

Cited By ~ 32

Author(s):

Hongmei Wang ◽

Jin-Yi Jiang ◽

Cheng Zhu ◽

Chun Peng ◽

Benjamin K. Tsang

Keyword(s):

Granulosa Cell ◽

Granulosa Cells ◽

Cell Apoptosis ◽

Nuclear Translocation ◽

Type I ◽

Follicular Atresia ◽

Down Regulation ◽

Activin Receptor ◽

Receptor Like Kinase ◽

Induced Apoptosis

Abstract Although the role of the TGF β superfamily members in the regulation of ovarian folliculogenesis has been extensively studied, their involvement in follicular atresia is not well understood. In the present study, we have demonstrated for the first time that Nodal, a member of the TGF β superfamily, is involved in promoting follicular atresia as evidenced by the following: 1) colocalization of Nodal and its type I receptor Activin receptor-like kinase 7 (ALK7) proteins in the granulosa cells was only observed in atretic antral follicles, whereas they were present in theca cells and granulosa cells of healthy follicles, respectively; 2) addition of recombinant Nodal or overexpression of Nodal by adenoviral infection induced apoptosis of otherwise healthy granulosa cells; 3) constitutively active ALK7 (ALK7-ca) overexpression mimicked the function of Nodal in the induction of granulosa cell apoptosis. Furthermore, overexpression of Nodal or ALK7-ca increased phosphorylation and nuclear translocation of Smad2, decreased X-linked inhibitor of apoptotic proteins (Xiap) expression at both mRNA and protein level and phospho-Akt content, as well as triggered mitochondrial release of death proteins Smac/DIABLO, Omi/HtrA2, and cytochrome c in the granulosa cells. Dominant-negative Smad2 significantly attenuated ALK7-ca-induced down-regulation of Xiap and thus rescued granulosa cells from undergoing apoptosis. In addition, whereas up-regulation of Xiap significantly attenuated ALK7-ca-induced apoptosis, down-regulation of Xiap sensitized granulosa cells to ALK7-ca-induced apoptosis. Furthermore, ALK7-ca-induced apoptosis was significantly attenuated by forced expression of activated Akt, and Akt rescued granulosa cells from undergoing apoptosis via proteasome-mediated ALK7 degradation. Taken together, Nodal plays an atretogenic role in the ovary where it induces granulosa cell apoptosis through activation of Smad2, down-regulation of the key survival molecules Xiap and phospho-Akt, as well as the activation of mitochondrial death pathway.

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SB-431542 Is a Potent and Specific Inhibitor of Transforming Growth Factor-β Superfamily Type I Activin Receptor-Like Kinase (ALK) Receptors ALK4, ALK5, and ALK7

Molecular Pharmacology ◽

10.1124/mol.62.1.65 ◽

2002 ◽

Vol 62 (1) ◽

pp. 65-74 ◽

Cited By ~ 1101

Author(s):

Gareth J. Inman ◽

Francisco J. Nicolás ◽

James F. Callahan ◽

John D. Harling ◽

Laramie M. Gaster ◽

...

Keyword(s):

Growth Factor ◽

Transforming Growth Factor ◽

Specific Inhibitor ◽

Transforming Growth Factor Β ◽

Type I ◽

Activin Receptor ◽

Receptor Like Kinase

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Hormonal regulation of expression of growth differentiation factor-9 receptor type I and II genes in the bovine ovarian follicle

Reproduction ◽

10.1530/rep.1.00885 ◽

2006 ◽

Vol 131 (3) ◽

pp. 545-553 ◽

Cited By ~ 24

Author(s):

Barana C Jayawardana ◽

Takashi Shimizu ◽

Hiromi Nishimoto ◽

Etsushi Kaneko ◽

Masafumi Tetsuka ◽

...

Keyword(s):

Mrna Expression ◽

Hormonal Regulation ◽

Ovarian Follicle ◽

Calf Serum ◽

Type I ◽

Mrna Levels ◽

Regulation Of Expression ◽

Differentiation Factor ◽

Growth Differentiation Factor 9 ◽

Alk 5

Growth differentiation factor-9 (GDF-9) and bone morphogenetic proteins (BMPs) are crucial factors in follicular growth and development. GDF-9 and BMPs initiate signaling by assembling type I (ALK-3, ALK-5 and ALK-6) and type II (BMPRII) receptors. However, the mechanism regulating the expression of these receptors in the process of bovine follicle development is still unknown. The aim of the present study was to clarify the involvement of receptor systems for GDF-9 and BMPs in follicular selection by examining the effects of FSH and estradiol-17β (E2) on the regulation of BMPRII, ALK-3, ALK-5 and ALK-6 mRNA expression in bovine granulosa cells (GCs). To observe mRNA expression during follicular development, follicles were obtained from heifers and classified into two groups: pre-selection follicles (PRFs) (an average of 7.7 mm follicles with low E2) and post-selection follicles (POFs) (an average of 15 mm follicles with high E2). Theca layer cells (TCs) and GCs were harvested from aspirated follicles. For in vitro studies, GCs were obtained from bovine follicles of 4–7 mm diameter and cultured in Dulbecco’s modified Eagle’s/F12 (DMEM/F-12) medium with 10% fetal calf serum for 24 h. The medium was then replaced with serum-free DMEM/F-12 supplemented with different doses of E2 (1, 10, 100 ng/ml) or FSH (1, 5, 10 ng/ml) or combinations of 1 ng/ml of E2 with different FSH doses. Total RNA was extracted and the mRNA expression of BMPRII, ALK-3, ALK-5 and ALK-6 was estimated by the quantitative real-time PCR method using a LightCycler. BMPRII and ALK-5 expression was significantly higher in the GCs of POFs than in those of PRFs, whereas ALK-3 expression was significantly lower in the GCs of POFs than in those of PRFs. There was no difference in ALK-6 expression in GCs between PRFs and POFs. The expression of BMPRII, ALK-5, ALK-3 and ALK-6 genes in the TCs was not significantly different between PRFs and POFs. Treatment of GCs with E2 alone increased BMPRII mRNA expression at a concentration of 100 ng/ml and ALK-5 mRNA expression at 10 ng/ml. BMPRII and ALK-5 mRNA levels were up-regulated by the combination of E2 (1 ng/ml) and FSH (5 ng/ml). On the other hand, FSH alone down-regulated the expression of BMPRII and ALK-5 in GCs. The results of the present study provide the first evidence that FSH and E2 regulate the expression of BMPRII and ALK-5 genes in bovine GCs. Thus, our data suggest that the GDF-9/BMPRII/ALK-5 system may be critically involved in the process of selection of bovine follicles.

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Activin B Induces Noncanonical SMAD1/5/8 Signaling via BMP Type I Receptors in Hepatocytes: Evidence for a Role in Hepcidin Induction by Inflammation in Male Mice

Endocrinology ◽

10.1210/en.2015-1747 ◽

2016 ◽

Vol 157 (3) ◽

pp. 1146-1162 ◽

Cited By ~ 54

Author(s):

Susanna Canali ◽

Amanda B. Core ◽

Kimberly B. Zumbrennen-Bullough ◽

Maria Merkulova ◽

Chia-Yu Wang ◽

...

Keyword(s):

Cell Types ◽

Similar Degree ◽

Type I ◽

Activin Receptor ◽

Hepcidin Expression ◽

Morphogenetic Protein ◽

Low Concentrations ◽

Receptor Like Kinase ◽

Anemia Of Inflammation

Abstract Induction of the iron regulatory hormone hepcidin contributes to the anemia of inflammation. Bone morphogenetic protein 6 (BMP6) signaling is a central regulator of hepcidin expression in the liver. Recently, the TGF-β/BMP superfamily member activin B was implicated in hepcidin induction by inflammation via noncanonical SMAD1/5/8 signaling, but its mechanism of action and functional significance in vivo remain uncertain. Here, we show that low concentrations of activin B, but not activin A, stimulate prolonged SMAD1/5/8 signaling and hepcidin expression in liver cells to a similar degree as canonical SMAD2/3 signaling, and with similar or modestly reduced potency compared with BMP6. Activin B stimulates hepcidin via classical activin type II receptors ACVR2A and ACVR2B, noncanonical BMP type I receptors activin receptor-like kinase 2 and activin receptor-like kinase 3, and SMAD5. The coreceptor hemojuvelin binds to activin B and facilitates activin B-SMAD1/5/8 signaling. Activin B-SMAD1/5/8 signaling has some selectivity for hepatocyte-derived cells and is not enabled by hemojuvelin in other cell types. Liver activin B mRNA expression is up-regulated in multiple mouse models of inflammation associated with increased hepcidin and hypoferremia, including lipopolysaccharide, turpentine, and heat-killed Brucella abortus models. Finally, the activin inhibitor follistatin-315 blunts hepcidin induction by lipopolysaccharide or B. abortus in mice. Our data elucidate a novel mechanism for noncanonical SMAD activation and support a likely functional role for activin B in hepcidin stimulation during inflammation in vivo.

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