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Castro K, Muradyan V, Flota P, Guanzon J, Poole N, Urrutia H, Eivers E. Drosophila Smad2 degradation occurs independently of linker phosphorylations. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001153. [PMID: 38601902 PMCID: PMC11004797 DOI: 10.17912/micropub.biology.001153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 03/13/2024] [Accepted: 03/22/2024] [Indexed: 04/12/2024]
Abstract
TGF-β signals are important for proliferation, differentiation, and cell fate determination during embryonic development and tissue homeostasis in adults. Drosophila Activin/TGF-β signals are transduced intracellularly when its transcription factor dSmad2 (also called Smad on X or Smox) is C-terminally phosphorylated by pathway receptors. Recently, it has been shown that receptor-activated dSmad2 undergoes bulk degradation, however, the mechanism of how this occurs is unknown. Here we investigated if two putative linker phosphorylation sites are involved in dSmad2 degradation. We demonstrate that degradation of activated-dSmad2 occurs independently of threonine phosphorylation at linker sites 252 and 277. We also show that dSmad2 degradation is not carried out by cellular proteasomes.
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Affiliation(s)
- Kenny Castro
- Biological Sciences, California State University Los Angeles, Los Angeles, California, United States
| | - Volodia Muradyan
- Biological Sciences, California State University Los Angeles, Los Angeles, California, United States
| | - Pablo Flota
- Biological Sciences, California State University Los Angeles, Los Angeles, California, United States
| | - John Guanzon
- Biological Sciences, California State University Los Angeles, Los Angeles, California, United States
| | - Neil Poole
- Biological Sciences, California State University Los Angeles, Los Angeles, California, United States
| | - Hugo Urrutia
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, United States
| | - Edward Eivers
- Biological Sciences, California State University Los Angeles, Los Angeles, California, United States
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2
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Similar sequences but dissimilar biological functions of GDF11 and myostatin. Exp Mol Med 2020; 52:1673-1693. [PMID: 33077875 PMCID: PMC8080601 DOI: 10.1038/s12276-020-00516-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/13/2020] [Accepted: 08/17/2020] [Indexed: 12/27/2022] Open
Abstract
Growth differentiation factor 11 (GDF11) and myostatin (MSTN) are closely related TGFβ family members that are often believed to serve similar functions due to their high homology. However, genetic studies in animals provide clear evidence that they perform distinct roles. While the loss of Mstn leads to hypermuscularity, the deletion of Gdf11 results in abnormal skeletal patterning and organ development. The perinatal lethality of Gdf11-null mice, which contrasts with the long-term viability of Mstn-null mice, has led most research to focus on utilizing recombinant GDF11 proteins to investigate the postnatal functions of GDF11. However, the reported outcomes of the exogenous application of recombinant GDF11 proteins are controversial partly because of the different sources and qualities of recombinant GDF11 used and because recombinant GDF11 and MSTN proteins are nearly indistinguishable due to their similar structural and biochemical properties. Here, we analyze the similarities and differences between GDF11 and MSTN from an evolutionary point of view and summarize the current understanding of the biological processing, signaling, and physiological functions of GDF11 and MSTN. Finally, we discuss the potential use of recombinant GDF11 as a therapeutic option for a wide range of medical conditions and the possible adverse effects of GDF11 inhibition mediated by MSTN inhibitors.
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3
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Wang Z, Lee G, Vuong R, Park JH. Two-factor specification of apoptosis: TGF-β signaling acts cooperatively with ecdysone signaling to induce cell- and stage-specific apoptosis of larval neurons during metamorphosis in Drosophila melanogaster. Apoptosis 2020; 24:972-989. [PMID: 31641960 DOI: 10.1007/s10495-019-01574-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Developmentally regulated programmed cell death (PCD) is one of the key cellular events for precise controlling of neuronal population during postembryonic development of the central nervous system. Previously we have shown that a group of corazonin-producing peptidergic neurons (vCrz) undergo apoptosis in response to ecdysone signaling via ecdysone receptor (EcR)-B isoforms and Ultraspiracle during early phase of metamorphosis. Further utilizing genetic, transgenic, and mosaic analyses, we have found that TGF-β signaling mediated by a glia-produced ligand, Myoglianin, type-I receptor Baboon (particularly Babo-A isoform) and dSmad2, is also required autonomously for PCD of the vCrz neurons. Our studies show that TGF-β signaling is not acting epistatically to EcR or vice versa. We also show that ectopic expression of a constitutively active phosphomimetic form of dSmad2 (dSmad2PM) is capable of inducing premature death of vCrz neurons in larva but not other larval neurons. Intriguingly, the dSmad2PM-mediated killing is completely suppressed by coexpression of a dominant-negative form of EcR (EcRDN), suggesting that EcR function is required for the proapoptotic dSmad2PM function. Based on these data, we suggest that TGF-β and ecdysone signaling pathways act cooperatively to induce vCrz neuronal PCD. We propose that this type of two-factor authentication is a key developmental strategy to ensure the timely PCD of specific larval neurons during metamorphosis.
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Affiliation(s)
- Zixing Wang
- UT-ORNL Graduate School of Genome Science and Technology Program, University of Tennessee, Knoxville, TN, 37996, USA
| | - Gyunghee Lee
- Department of Biochemistry and Cellular and Molecular Biology and NeuroNet Research Center, University of Tennessee, Knoxville, TN, 37996, USA
| | - Richard Vuong
- Undergraduate program in Neuroscience, University of Tennessee, Knoxville, TN, 37996, USA
| | - Jae H Park
- Department of Biochemistry and Cellular and Molecular Biology and NeuroNet Research Center, University of Tennessee, Knoxville, TN, 37996, USA. .,UT-ORNL Graduate School of Genome Science and Technology Program, University of Tennessee, Knoxville, TN, 37996, USA.
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4
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Upadhyay A, Peterson AJ, Kim MJ, O'Connor MB. Muscle-derived Myoglianin regulates Drosophila imaginal disc growth. eLife 2020; 9:e51710. [PMID: 32633716 PMCID: PMC7371420 DOI: 10.7554/elife.51710] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 07/04/2020] [Indexed: 01/05/2023] Open
Abstract
Organ growth and size are finely tuned by intrinsic and extrinsic signaling molecules. In Drosophila, the BMP family member Dpp is produced in a limited set of imaginal disc cells and functions as a classic morphogen to regulate pattern and growth by diffusing throughout imaginal discs. However, the role of TGFβ/Activin-like ligands in disc growth control remains ill-defined. Here, we demonstrate that Myoglianin (Myo), an Activin family member, and a close homolog of mammalian Myostatin (Mstn), is a muscle-derived extrinsic factor that uses canonical dSmad2-mediated signaling to regulate wing size. We propose that Myo is a myokine that helps mediate an allometric relationship between muscles and their associated appendages.
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Affiliation(s)
- Ambuj Upadhyay
- Department of Genetics, Cell Biology and Development University of MinnesotaMinneapolisUnited States
| | - Aidan J Peterson
- Department of Genetics, Cell Biology and Development University of MinnesotaMinneapolisUnited States
| | - Myung-Jun Kim
- Department of Genetics, Cell Biology and Development University of MinnesotaMinneapolisUnited States
| | - Michael B O'Connor
- Department of Genetics, Cell Biology and Development University of MinnesotaMinneapolisUnited States
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5
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Wisotzkey RG, Newfeld SJ. TGF-β Prodomain Alignments Reveal Unexpected Cysteine Conservation Consistent with Phylogenetic Predictions of Cross-Subfamily Heterodimerization. Genetics 2020; 214:447-465. [PMID: 31843757 PMCID: PMC7017013 DOI: 10.1534/genetics.119.302255] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 12/05/2019] [Indexed: 02/07/2023] Open
Abstract
Evolutionary relationships between prodomains in the TGF-β family have gone unanalyzed due to a perceived lack of conservation. We developed a novel approach, identified these relationships, and suggest hypotheses for new regulatory mechanisms in TGF-β signaling. First, a quantitative analysis placed each family member from flies, mice, and nematodes into the Activin, BMP, or TGF-β subfamily. Second, we defined the prodomain and ligand via the consensus cleavage site. Third, we generated alignments and trees from the prodomain, ligand, and full-length sequences independently for each subfamily. Prodomain alignments revealed that six structural features of 17 are well conserved: three in the straitjacket and three in the arm. Alignments also revealed unexpected cysteine conservation in the "LTBP-Association region" upstream of the straitjacket and in β8 of the bowtie in 14 proteins from all three subfamilies. In prodomain trees, eight clusters across all three subfamilies were present that were not seen in the ligand or full-length trees, suggesting prodomain-mediated cross-subfamily heterodimerization. Consistency between cysteine conservation and prodomain clustering provides support for heterodimerization predictions. Overall, our analysis suggests that cross-subfamily interactions are more common than currently appreciated and our predictions generate numerous testable hypotheses about TGF-β function and evolution.
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Affiliation(s)
| | - Stuart J Newfeld
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287-4501
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6
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Farrukh F, Davies E, Berry M, Logan A, Ahmed Z. BMP4/Smad1 Signalling Promotes Spinal Dorsal Column Axon Regeneration and Functional Recovery After Injury. Mol Neurobiol 2019; 56:6807-6819. [PMID: 30924076 PMCID: PMC6728286 DOI: 10.1007/s12035-019-1555-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 03/13/2019] [Indexed: 01/08/2023]
Abstract
Signalling through the BMP4/Smad1 pathway promotes corticospinal tract axon regeneration and functional recovery in mice. However, unlike humans and rats, mice do not cavitate. Here, we investigated if activation of the BMP4/Smad1 pathway promotes axon regeneration and functional recovery in a rat model that cavitates. We show that dorsal root ganglion neurons (DRGN) in injury models, including the non-regenerating dorsal column (DC) and the regenerating sciatic nerve (SN) crush and preconditioning (p) SN + DC (pSN + DC) paradigms, regulate the BMP4/Smad1 signalling pathway. For example, mRNA expression of positive regulators of the BMP4/Smad1 pathway was highly up-regulated whilst negative regulators were significantly down-regulated in DRGN in the regenerating SN and pSN + DC models compared to non-regenerating DC models, matched by concomitant changes in protein expression detected in DRGN by immunohistochemistry. BMP4 peptide promoted significant DRGN survival and disinhibited neurite outgrowth in vitro, whilst AAV-BMP4 delivery in vivo stimulated DC axon regeneration and functional recovery in a model that cavitates. Our results show that activation of the BMP4/Smad1 pathway is a potential therapeutic target in the search for axon regenerative signalling pathways in the CNS.
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Affiliation(s)
- Fatima Farrukh
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Elise Davies
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Martin Berry
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Ann Logan
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Zubair Ahmed
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
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7
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Jordán-Álvarez S, Santana E, Casas-Tintó S, Acebes Á, Ferrús A. The equilibrium between antagonistic signaling pathways determines the number of synapses in Drosophila. PLoS One 2017; 12:e0184238. [PMID: 28892511 PMCID: PMC5593197 DOI: 10.1371/journal.pone.0184238] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 08/21/2017] [Indexed: 12/12/2022] Open
Abstract
The number of synapses is a major determinant of behavior and many neural diseases exhibit deviations in that number. However, how signaling pathways control this number is still poorly understood. Using the Drosophila larval neuromuscular junction, we show here a PI3K-dependent pathway for synaptogenesis which is functionally connected with other previously known elements including the Wit receptor, its ligand Gbb, and the MAPkinases cascade. Based on epistasis assays, we determined the functional hierarchy within the pathway. Wit seems to trigger signaling through PI3K, and Ras85D also contributes to the initiation of synaptogenesis. However, contrary to other signaling pathways, PI3K does not require Ras85D binding in the context of synaptogenesis. In addition to the MAPK cascade, Bsk/JNK undergoes regulation by Puc and Ras85D which results in a narrow range of activity of this kinase to determine normalcy of synapse number. The transcriptional readout of the synaptogenesis pathway involves the Fos/Jun complex and the repressor Cic. In addition, we identified an antagonistic pathway that uses the transcription factors Mad and Medea and the microRNA bantam to down-regulate key elements of the pro-synaptogenesis pathway. Like its counterpart, the anti-synaptogenesis signaling uses small GTPases and MAPKs including Ras64B, Ras-like-a, p38a and Licorne. Bantam downregulates the pro-synaptogenesis factors PI3K, Hiw, Ras85D and Bsk, but not AKT. AKT, however, can suppress Mad which, in conjunction with the reported suppression of Mad by Hiw, closes the mutual regulation between both pathways. Thus, the number of synapses seems to result from the balanced output from these two pathways.
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Affiliation(s)
| | | | | | - Ángel Acebes
- Institute Cajal C.S.I.C., Madrid, Spain
- * E-mail: (AF); (AA)
| | - Alberto Ferrús
- Institute Cajal C.S.I.C., Madrid, Spain
- * E-mail: (AF); (AA)
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8
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Augustin H, McGourty K, Steinert JR, Cochemé HM, Adcott J, Cabecinha M, Vincent A, Halff EF, Kittler JT, Boucrot E, Partridge L. Myostatin-like proteins regulate synaptic function and neuronal morphology. Development 2017; 144:2445-2455. [PMID: 28533206 PMCID: PMC5536874 DOI: 10.1242/dev.152975] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 05/15/2017] [Indexed: 12/27/2022]
Abstract
Growth factors of the TGFβ superfamily play key roles in regulating neuronal and muscle function. Myostatin (or GDF8) and GDF11 are potent negative regulators of skeletal muscle mass. However, expression of myostatin and its cognate receptors in other tissues, including brain and peripheral nerves, suggests a potential wider biological role. Here, we show that Myoglianin (MYO), the Drosophila homolog of myostatin and GDF11, regulates not only body weight and muscle size, but also inhibits neuromuscular synapse strength and composition in a Smad2-dependent manner. Both myostatin and GDF11 affected synapse formation in isolated rat cortical neuron cultures, suggesting an effect on synaptogenesis beyond neuromuscular junctions. We also show that MYO acts in vivo to inhibit synaptic transmission between neurons in the escape response neural circuit of adult flies. Thus, these anti-myogenic proteins act as important inhibitors of synapse function and neuronal growth. Summary: Myostatin-like proteins can modulate neuromuscular synapse strength as well as synaptogenesis beyond neuromuscular junctions, highlighting a key role for these proteins in synapse function and neuronal growth.
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Affiliation(s)
- Hrvoje Augustin
- Institute of Healthy Ageing, and GEE, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK.,Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, Cologne D-50931, Germany
| | - Kieran McGourty
- Institute of Structural and Molecular Biology, University College London, Darwin Building Gower Street, London WC1E 6BT, UK
| | - Joern R Steinert
- MRC Toxicology Unit, Hodgkin Building, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
| | - Helena M Cochemé
- Institute of Healthy Ageing, and GEE, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK.,Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, Cologne D-50931, Germany.,MRC Clinical Sciences Centre, Du Cane Road, London W12 0NN, UK.,Institute of Clinical Sciences, Imperial College London, ICTEM Building, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK
| | - Jennifer Adcott
- Institute of Healthy Ageing, and GEE, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK.,Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, Cologne D-50931, Germany
| | - Melissa Cabecinha
- Institute of Healthy Ageing, and GEE, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Alec Vincent
- Institute of Healthy Ageing, and GEE, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Els F Halff
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
| | - Josef T Kittler
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
| | - Emmanuel Boucrot
- Institute of Structural and Molecular Biology, University College London, Darwin Building Gower Street, London WC1E 6BT, UK
| | - Linda Partridge
- Institute of Healthy Ageing, and GEE, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK .,Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, Cologne D-50931, Germany
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9
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Abstract
Studies in mammals and Drosophila have demonstrated the existence and significance of secreted factors involved in communication between distal organs. In this review, primarily focusing on Drosophila, we examine the known interorgan communication factors and their functions, physiological inducers, and integration in regulating physiology. Moreover, we describe how organ-sensing screens in Drosophila can systematically identify novel conserved interorgan communication factors. Finally, we discuss how interorgan communication enabled and evolved as a result of specialization of organs. Together, we anticipate that future studies will establish a model for metazoan interorgan communication network (ICN) and how it is deregulated in disease.
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Affiliation(s)
- Ilia A Droujinine
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115; ,
| | - Norbert Perrimon
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115; ,
- Howard Hughes Medical Institute, Boston, Massachusetts 02115
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10
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Kashima R, Roy S, Ascano M, Martinez-Cerdeno V, Ariza-Torres J, Kim S, Louie J, Lu Y, Leyton P, Bloch KD, Kornberg TB, Hagerman PJ, Hagerman R, Lagna G, Hata A. Augmented noncanonical BMP type II receptor signaling mediates the synaptic abnormality of fragile X syndrome. Sci Signal 2016; 9:ra58. [PMID: 27273096 DOI: 10.1126/scisignal.aaf6060] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Epigenetic silencing of fragile X mental retardation 1 (FMR1) causes fragile X syndrome (FXS), a common inherited form of intellectual disability and autism. FXS correlates with abnormal synapse and dendritic spine development, but the molecular link between the absence of the FMR1 product FMRP, an RNA binding protein, and the neuropathology is unclear. We found that the messenger RNA encoding bone morphogenetic protein type II receptor (BMPR2) is a target of FMRP. Depletion of FMRP increased BMPR2 abundance, especially that of the full-length isoform that bound and activated LIM domain kinase 1 (LIMK1), a component of the noncanonical BMP signal transduction pathway that stimulates actin reorganization to promote neurite outgrowth and synapse formation. Heterozygosity for BMPR2 rescued the morphological abnormalities in neurons both in Drosophila and in mouse models of FXS, as did the postnatal pharmacological inhibition of LIMK1 activity. Compared with postmortem prefrontal cortex tissue from healthy subjects, the amount of full-length BMPR2 and of a marker of LIMK1 activity was increased in this brain region from FXS patients. These findings suggest that increased BMPR2 signal transduction is linked to FXS and that the BMPR2-LIMK1 pathway is a putative therapeutic target in patients with FXS and possibly other forms of autism.
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Affiliation(s)
- Risa Kashima
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Sougata Roy
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Manuel Ascano
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Veronica Martinez-Cerdeno
- Institute for Pediatric Regenerative Medicine, Department of Pathology, University of California, Davis, Davis, CA 95817, USA. MIND (Medical Investigation of Neurodevelopmental Disorders) Institute, University of California, Davis, Davis, CA 95817, USA
| | - Jeanelle Ariza-Torres
- Institute for Pediatric Regenerative Medicine, Department of Pathology, University of California, Davis, Davis, CA 95817, USA
| | - Sunghwan Kim
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Justin Louie
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Yao Lu
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Patricio Leyton
- Anesthesia and Critical Care, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Kenneth D Bloch
- Anesthesia and Critical Care, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Thomas B Kornberg
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Paul J Hagerman
- Department of Biochemistry and Molecular Medicine, University of California, Davis, Davis, CA 95817, USA
| | - Randi Hagerman
- MIND (Medical Investigation of Neurodevelopmental Disorders) Institute, University of California, Davis, Davis, CA 95817, USA
| | - Giorgio Lagna
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Akiko Hata
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA.
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11
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Lee JH, Momani J, Kim YM, Kang CK, Choi JH, Baek HJ, Kim HW. Effective RNA-silencing strategy of Lv-MSTN/GDF11 gene and its effects on the growth in shrimp, Litopenaeus vannamei. Comp Biochem Physiol B Biochem Mol Biol 2015; 179:9-16. [DOI: 10.1016/j.cbpb.2014.09.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 09/04/2014] [Accepted: 09/12/2014] [Indexed: 11/26/2022]
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12
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Peterson AJ, O'Connor MB. Strategies for exploring TGF-β signaling in Drosophila. Methods 2014; 68:183-93. [PMID: 24680699 PMCID: PMC4057889 DOI: 10.1016/j.ymeth.2014.03.016] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 03/14/2014] [Accepted: 03/17/2014] [Indexed: 02/06/2023] Open
Abstract
The TGF-β pathway is an evolutionarily conserved signal transduction module that mediates diverse biological processes in animals. In Drosophila, both the BMP and Activin branches are required for viability. Studies rooted in classical and molecular genetic approaches continue to uncover new developmental roles for TGF-β signaling. We present an overview of the secreted ligands, transmembrane receptors and cellular Smad transducer proteins that compose the core pathway in Drosophila. An assortment of tools have been developed to conduct tissue-specific loss- and gain-of-function experiments for these pathway components. We discuss the deployment of these reagents, with an emphasis on appropriate usage and limitations of the available tools. Throughout, we note reagents that are in need of further improvement or development, and signaling features requiring further study. A general theme is that comparison of phenotypes for ligands, receptors, and Smads can be used to map tissue interactions, and to separate canonical and non-canonical signaling activities. Core TGF-β signaling components are subject to multiple layers of regulation, and are coupled to context-specific inputs and outputs. In addition to fleshing out how TGF-β signaling serves the fruit fly, we anticipate that future studies will uncover new regulatory nodes and modes and will continue to advance paradigms for how TGF-β signaling regulates general developmental processes.
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Affiliation(s)
- Aidan J Peterson
- Department of Genetics, Cell Biology & Development, 6-160 Jackson Hall, 321 Church St SE, University of Minnesota, Minneapolis, MN 55455, United States
| | - Michael B O'Connor
- Department of Genetics, Cell Biology & Development, 6-160 Jackson Hall, 321 Church St SE, University of Minnesota, Minneapolis, MN 55455, United States.
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13
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Marmion RA, Jevtic M, Springhorn A, Pyrowolakis G, Yakoby N. The Drosophila BMPRII, wishful thinking, is required for eggshell patterning. Dev Biol 2012; 375:45-53. [PMID: 23274688 DOI: 10.1016/j.ydbio.2012.12.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 10/13/2012] [Accepted: 12/13/2012] [Indexed: 10/27/2022]
Abstract
The Drosophila eggshell is an elaborate structure that is derived from a monolayer of follicular epithelium surrounding the developing oocyte within the female ovary. The bone morphogenetic protein (BMP) signaling pathway is essential for controlling the patterning and morphogenesis of the eggshell. During oogenesis, the roles of patterning and morphogenesis by the BMP type I receptor thickveins (tkv) have been studied extensively. However, signaling through this pathway requires both type I and II receptors, and the latter has yet to be established in oogenesis. We focus on wishful thinking (wit), the Drosophila homolog to the mammalian BMP type II receptor, BMPRII. We found that wit is expressed dynamically in the FCs of D. melanogaster in an evolutionary conserved pattern. The expression patterns are highly correlated with the dynamics of the BMP signaling, which is consistent with our finding that wit is a target of BMP signaling. Furthermore, we established that WIT is necessary for BMP signaling, and loss of WIT is associated with cell autonomous loss of BMP responses. Of importance, we demonstrated that perturbations in WIT led to changes in eggshell morphologies in domains that are patterned by BMP signaling. Previous studies have shown a role for WIT in BMP signaling during neurogenesis; however, our results reveal a role for WIT in epithelial cells' development.
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Affiliation(s)
- Robert A Marmion
- Department of Biology and Center for Computational and Integrative Biology, Rutgers, The State University of NJ, Camden, NJ, USA
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14
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De Santis C, Wade NM, Jerry DR, Preston NP, Glencross BD, Sellars MJ. Growing backwards: an inverted role for the shrimp ortholog of vertebrate myostatin and GDF11. ACTA ACUST UNITED AC 2011; 214:2671-7. [PMID: 21795562 DOI: 10.1242/jeb.056374] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Myostatin (MSTN) and growth differentiation factor-11 (GDF11) are closely related proteins involved in muscle cell growth and differentiation as well as neurogenesis of vertebrates. Both MSTN and GDF11 negatively regulate their functions. Invertebrates possess a single ortholog of the MSTN/GDF11 family. In order to understand the role of MSTN/GDF11 in crustaceans, the gene ortholog was identified and characterized in the penaeid shrimp Penaeus monodon. The overall protein sequence and specific functional sites were highly conserved with other members of the MSTN/GDF11 family. Gene transcripts of pmMstn/Gdf11, assessed by real-time PCR, were detected in a variety of tissue types and were actively regulated in muscle across the moult cycle. To assess phenotypic function in shrimp, pmMstn/Gdf11 gene expression was downregulated by tail-muscle injection of sequence-specific double-stranded RNA. Shrimp with reduced levels of pmMstn/Gdf11 transcripts displayed a dramatic slowing in growth rate compared with control groups. Findings from this study place the MSTN/GDF11 gene at the centre of growth regulation in shrimp, but suggest that, compared with higher vertebrates, this gene has an opposite role in invertebrates such as shrimp, where levels of gene expression may positively regulate growth.
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Affiliation(s)
- Christian De Santis
- Aquaculture Genetics Research Program, School of Marine and Tropical Biology, James Cook University, Townsville, QLD 4811, Australia
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Awasaki T, Huang Y, O'Connor MB, Lee T. Glia instruct developmental neuronal remodeling through TGF-β signaling. Nat Neurosci 2011; 14:821-3. [PMID: 21685919 PMCID: PMC3337551 DOI: 10.1038/nn.2833] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Accepted: 04/11/2011] [Indexed: 11/14/2022]
Abstract
Neural circuits are remodeled in response to developmental and environmental cues. Here we show that glia secrets Myoglianin, a TGF-β ligand, to instruct developmental neural remodeling in Drosophila. Glial Myoglianin up-regulates neuronal expression of an ecdysone nuclear receptor that triggers neurite remodeling following the late-larval ecdysone peak. This observation reveals that glia orchestrate developmental neural remodeling not only via engulfment of unwanted neurites but also through enabling neuron remodeling.
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Affiliation(s)
- Takeshi Awasaki
- Department of Neurobiology, University of Massachusetts, Worcester, Massachusetts, USA.
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Drosophila TIEG is a modulator of different signalling pathways involved in wing patterning and cell proliferation. PLoS One 2011; 6:e18418. [PMID: 21494610 PMCID: PMC3072976 DOI: 10.1371/journal.pone.0018418] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 03/07/2011] [Indexed: 11/19/2022] Open
Abstract
Acquisition of a final shape and size during organ development requires a
regulated program of growth and patterning controlled by a complex genetic
network of signalling molecules that must be coordinated to provide positional
information to each cell within the corresponding organ or tissue. The mechanism
by which all these signals are coordinated to yield a final response is not well
understood. Here, I have characterized the Drosophila ortholog
of the human TGF-β Inducible Early Gene 1 (dTIEG). TIEG are zinc-finger
proteins that belong to the Krüppel-like factor (KLF) family and were
initially identified in human osteoblasts and pancreatic tumor cells for the
ability to enhance TGF-β response. Using the developing wing of
Drosophila as “in vivo” model, the dTIEG
function has been studied in the control of cell proliferation and patterning.
These results show that dTIEG can modulate Dpp signalling. Furthermore, dTIEG
also regulates the activity of JAK/STAT pathway suggesting a conserved role of
TIEG proteins as positive regulators of TGF-β signalling and as mediators of
the crosstalk between signalling pathways acting in a same cellular context.
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Hu X, Guo H, He Y, Wang S, Zhang L, Wang S, Huang X, Roy SW, Lu W, Hu J, Bao Z. Molecular characterization of Myostatin gene from Zhikong scallop Chlamys farreri (Jones et Preston 1904). Genes Genet Syst 2011; 85:207-18. [PMID: 21041979 DOI: 10.1266/ggs.85.207] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The scallop is an economically important sea food prized for its large and delicious adductor muscle. Studying the molecular basis of scallop muscle growth is important for both scallop breeding and our understanding of muscle mass regulation in bivalve. Myostatin (MSTN) is a conserved negative regulator of muscle growth and development. Here we report the MSTN gene from Zhikong scallop (Chlamys farreri Jones et Preston 1904). The C. farreri MSTN consists of 11651 nucleotides encoding 457 amino acids. The gene has a 3-exon/2-intron structure that is conserved with vertebrate homologs. The exons are 586, 380 and 408 bp in length, respectively, and separated by introns of 5086 and 1518 bp. The protein sequence contains characteristic conserved residues including a cleavage motif of proteolysis (RXXR) and nine cysteines. Three transcription initiation sites were found at 62, 146, and 296 bp upstream of the translation start codon ATG. In silico analysis of the promoter region identified a TATA-box and several muscle-specific regulatory elements including COMP, MEF2s, MTBFs and E-boxes. Minisatellite DNA was found in intron 1. By fluorescence in situ hybridization (FISH), the gene was mapped to the long arm of a pair of middle subtelocentric chromosome. Quantitative analysis of MSTN transcripts in embryos/larvae indicated high expression level in gastrulae and limited expression at other stages. In adult scallops, MSTN is predominantly expressed in striated muscle, with different expression levels in other tissues. Our data provide valuable genomic and expression information which will aid the further study on scallop MSTN function and MSTN evolution.
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Affiliation(s)
- Xiaoli Hu
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, China
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Saina M, Technau U. Characterization of myostatin/gdf8/11 in the starlet sea anemone Nematostella vectensis. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2009; 312:780-8. [PMID: 19533681 DOI: 10.1002/jez.b.21304] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The signaling molecule Myostatin, a member of the TGF-beta superfamily, is crucially involved in the control of muscle growth and development in triploblastic organisms. A homolog to vertebrate myostatin and gdf8/11 was isolated from a diploblastic cnidarian, the starlet sea anemone Nematostella vectensis. Here we provide a detailed characterization of the Nematostella myostatin/gdf8/11 gene and show the first analysis of gene expression in adult polyps. This analysis revealed that myostatin/gdf8/11 is expressed in the mesenteries, which are endodermal folds, and weakly in the body wall endoderm, but largely excluded from the areas of muscle formation, the retractor and the parietal muscle. Contrary to this, in vertebrates the muscle growth inhibitor myostatin is expressed in the muscle tissue. We therefore hypothesize that myostatin/gdf8/11 in Nematostella is involved in regulating nonmuscle cell differentiation, possibly by repressing muscle differentiation.
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Affiliation(s)
- Michael Saina
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
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Jensen PA, Zheng X, Lee T, O’Connor MB. The Drosophila Activin-like ligand Dawdle signals preferentially through one isoform of the Type-I receptor Baboon. Mech Dev 2009; 126:950-7. [PMID: 19766717 PMCID: PMC2798586 DOI: 10.1016/j.mod.2009.09.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Revised: 08/31/2009] [Accepted: 09/05/2009] [Indexed: 11/17/2022]
Abstract
How TGF-beta-type ligands achieve signaling specificity during development is only partially understood. Here, we show that Dawdle, one of four Activin-type ligands in Drosophila, preferentially signals through Babo(c), one of three isoforms of the Activin Type-I receptor that are expressed during development. In cell culture, Dawdle signaling is active in the presence of the Type-II receptor Punt but not Wit, demonstrating that the Type-II receptor also contributes to the specificity of the signaling complex. During development, different larval tissues express unique combinations of these receptors, and ectopic expression of Babo(c) in a tissue where it is not normally expressed at high levels can make that tissue sensitive to Dawdle signaling. These results reveal a mechanism by which distinct cell types can discriminate between different Activin-type signals during development as a result of differential expression of Type-I receptor isoforms.
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Affiliation(s)
- Philip A. Jensen
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN 55455
| | - Xiaoyan Zheng
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Tzumin Lee
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Michael B. O’Connor
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN 55455
- HHMI, University of Minnesota, Minneapolis, MN 55455
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Abstract
Transforming growth factor beta (TGFbeta) pathways are implicated in metazoan development, adult homeostasis and disease. TGFbeta ligands signal via receptor serine/threonine kinases that phosphorylate, and activate, intracellular Smad effectors as well as other signaling proteins. Oligomeric Smad complexes associate with chromatin and regulate transcription, defining the biological response of a cell to TGFbeta family members. Signaling is modulated by negative-feedback regulation via inhibitory Smads. We review here the mechanisms of TGFbeta signal transduction in metazoans and emphasize events crucial for embryonic development.
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Pentek J, Parker L, Wu A, Arora K. Follistatin preferentially antagonizes activin rather than BMP signaling inDrosophila. Genesis 2009; 47:261-73. [DOI: 10.1002/dvg.20486] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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22
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Ng J. TGF-beta signals regulate axonal development through distinct Smad-independent mechanisms. Development 2008; 135:4025-35. [PMID: 19004854 DOI: 10.1242/dev.028209] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Proper nerve connections form when growing axons terminate at the correct postsynaptic target. Here I show that Transforming growth factor beta (TGFbeta) signals regulate axon growth. In most contexts, TGFbeta signals are tightly linked to Smad transcriptional activity. Although known to exist, how Smad-independent pathways mediate TGFbeta responses in vivo is unclear. In Drosophila mushroom body (MB) neurons, loss of the TGFbeta receptor Baboon (Babo) results in axon overextension. Conversely, misexpression of constitutively active Babo results in premature axon termination. Smad activity is not required for these phenotypes. This study shows that Babo signals require the Rho GTPases Rho1 and Rac, and LIM kinase1 (LIMK1), which regulate the actin cytoskeleton. Contrary to the well-established receptor activation model, in which type 1 receptors act downstream of type 2 receptors, this study shows that the type 2 receptors Wishful thinking (Wit) and Punt act downstream of the Babo type 1 receptor. Wit and Punt regulate axon growth independently, and interchangeably, through LIMK1-dependent and -independent mechanisms. Thus, novel TGFbeta receptor interactions control non-Smad signals and regulate multiple aspects of axonal development in vivo.
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Affiliation(s)
- Julian Ng
- MRC Centre for Developmental Neurobiology, New Hunt's House, Guy's Campus, King's College London, SE1 1UL, UK.
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Covi JA, Kim HW, Mykles DL. Expression of alternatively spliced transcripts for a myostatin-like protein in the blackback land crab, Gecarcinus lateralis. Comp Biochem Physiol A Mol Integr Physiol 2008; 150:423-30. [DOI: 10.1016/j.cbpa.2008.04.608] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2008] [Revised: 04/24/2008] [Accepted: 04/30/2008] [Indexed: 01/17/2023]
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TGFbeta signaling in Tribolium: vertebrate-like components in a beetle. Dev Genes Evol 2008; 218:203-13. [PMID: 18392881 DOI: 10.1007/s00427-007-0179-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2007] [Accepted: 08/23/2007] [Indexed: 02/01/2023]
Abstract
The cytokines of the TGFbeta superfamily are highly conserved in evolution and elicit a diverse range of cellular responses in all metazoa. In Drosophila, the signaling pathways of the two TGFbeta subfamilies, Activins and Bone Morphogenetic Proteins (BMPs), have been well studied. To address the question of whether the findings from Drosophila are representative of insects in general, we analyzed the components of TGFbeta-signaling present in the genome of the beetle Tribolium castaneum. We were able to identify orthologs of the BMPs Decapentaplegic and Glass bottom boat, of the Activins Activinbeta and Dawdle, as well as orthologs of the less well-known ligands Myoglianin and Maverick, together with orthologs of all TGFbeta receptors and cytoplasmic signal transducers present in Drosophila. This indicates that the diversity of TGFbeta signaling components is generally well conserved between Drosophila and Tribolium. However, the genome of the beetle-and of the bee Apis mellifera-lacks an ortholog of the Drosophila BMP Screw but does contain a vertebrate-like BMP10 homolog which is not found in Drosophila. Concerning BMP inhibitors, Tribolium displays an even more vertebrate-like ensemble of components. We found two orthologs of the vertebrate DAN family, Dan and Gremlin, and show embryonic expression of a vertebrate-like BAMBI ortholog, all of which are absent in Drosophila. This suggests that Tribolium might have retained a more ancestral composition of TGFbeta signaling components and that TGFbeta signaling underwent considerable change in the Drosophila lineage. Tribolium is an excellent model to study the function of these ancestral signaling components in insects.
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25
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The BMP ligand Gbb gates the expression of synaptic homeostasis independent of synaptic growth control. Neuron 2008; 56:109-23. [PMID: 17920019 DOI: 10.1016/j.neuron.2007.08.006] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2007] [Revised: 06/03/2007] [Accepted: 07/08/2007] [Indexed: 11/20/2022]
Abstract
Inhibition of postsynaptic glutamate receptors at the Drosophila NMJ initiates a compensatory increase in presynaptic release termed synaptic homeostasis. BMP signaling is necessary for normal synaptic growth and stability. It remains unknown whether BMPs have a specific role during synaptic homeostasis and, if so, whether BMP signaling functions as an instructive retrograde signal that directly modulates presynaptic transmitter release. Here, we demonstrate that the BMP receptor (Wit) and ligand (Gbb) are necessary for the rapid induction of synaptic homeostasis. We also provide evidence that both Wit and Gbb have functions during synaptic homeostasis that are separable from NMJ growth. However, further genetic experiments demonstrate that Gbb does not function as an instructive retrograde signal during synaptic homeostasis. Rather, our data indicate that Wit and Gbb function via the downstream transcription factor Mad and that Mad-mediated signaling is continuously required during development to confer competence of motoneurons to express synaptic homeostasis.
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26
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Du R, An XR, Chen YF, Qin J. Some Motifs Were Important for Myostatin Transcriptional Regulation in Sheep (Ovis aries). BMB Rep 2007; 40:547-53. [PMID: 17669271 DOI: 10.5483/bmbrep.2007.40.4.547] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Many motifs along the 1.2 kb myostatin promoter (MSTNpro) in sheep have been found by the MatInspecter program in our recent study. To further verify the role of the motifs and better understand the transcriptional regulation mechanism of the myostatin gene in sheep, the reporter gene EGFP (enhanced green fluorescent protein) was selected and the wild-type (W) vector MSTNPro(W)-EGFP or motif-mutational (M) vector MSTNPro(M)-EGFP were constructed. The transcriptional regulation activities were analyzed by detecting the fluorescence strength of EGFP in C2C12 myoblasts transfected with the vectors. The results showed that E-box (E) 3, E4, E5 and E7, particularly E3, E5 and E7, had important effects on the activity of the 1.2 kb sheep myostatin promoter. In addition, we also detected several other important motifs such as MTBF (muscle-specific Mt binding factor), MEF2 (myocyte enhancer factor 2), GRE (glucocorticoid response elements) and PRE (progesterone response elements) along the sheep myostatin promoter by the mutational analysis.
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Affiliation(s)
- Rong Du
- State Key Laboratory for Agrobiotechnology, College of Biological Science, China Agricultural University, Beijing, 100094, P.R. China
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Parker L, Ellis JE, Nguyen MQ, Arora K. The divergent TGF-β ligand Dawdle utilizes an activin pathway to influence axon guidance inDrosophila. Development 2006; 133:4981-91. [PMID: 17119022 DOI: 10.1242/dev.02673] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Axon guidance is regulated by intrinsic factors and extrinsic cues provided by other neurons, glia and target muscles. Dawdle (Daw), a divergent TGF-β superfamily ligand expressed in glia and mesoderm, is required for embryonic motoneuron pathfinding in Drosophila. In dawmutants, ISNb and SNa axons fail to extend completely and are unable to innervate their targets. We find that Daw initiates an activin signaling pathway via the receptors Punt and Baboon (Babo) and the signal-transducer Smad2. Furthermore, mutations in these signaling components display similar axon guidance defects. Cell-autonomous disruption of receptor signaling suggests that Babo is required in motoneurons rather than in muscles or glia. Ectopic ligand expression can rescue the daw phenotype, but has no deleterious effects. Our results indicate that Daw functions in a permissive manner to modulate or enable the growth cone response to other restricted guidance cues,and support a novel role for activin signaling in axon guidance.
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Affiliation(s)
- Louise Parker
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA 92697-2300, USA
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