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Li L, Zhang N, Beati SAH, De Las Heras Chanes J, di Pietro F, Bellaiche Y, Müller HAJ, Großhans J. Kinesin-1 patterns Par-1 and Rho signaling at the cortex of syncytial embryos of Drosophila. J Cell Biol 2024; 223:e202206013. [PMID: 37955925 PMCID: PMC10641515 DOI: 10.1083/jcb.202206013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 03/23/2023] [Accepted: 10/18/2023] [Indexed: 11/14/2023] Open
Abstract
The cell cortex of syncytial Drosophila embryos is patterned into cap and intercap regions by centrosomes, specific sets of proteins that are restricted to their respective regions by unknown mechanisms. Here, we found that Kinesin-1 is required for the restriction of plus- and minus-ends of centrosomal and non-centrosomal microtubules to the cap region, marked by EB1 and Patronin/Shot, respectively. Kinesin-1 also directly or indirectly restricts proteins and Rho signaling to the intercap, including the RhoGEF Pebble, Dia, Myosin II, Capping protein-α, and the polarity protein Par-1. Furthermore, we found that Par-1 is required for cap restriction of Patronin/Shot, and vice versa Patronin, for Par-1 enrichment at the intercap. In summary, our data support a model that Kinesin-1 would mediate the restriction of centrosomal and non-centrosomal microtubules to a region close to the centrosomes and exclude Rho signaling and Par-1. In addition, mutual antagonistic interactions would refine and maintain the boundary between cap and intercap and thus generate a distinct cortical pattern.
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Affiliation(s)
- Long Li
- Department of Biology, Philipps University, Marburg, Germany
| | - Na Zhang
- Department of Biology, Philipps University, Marburg, Germany
| | - Seyed Amir Hamze Beati
- Division of Developmental Genetics, Institute for Biology, University of Kassel, Kassel, Germany
| | - Jose De Las Heras Chanes
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR 3215, Inserm U934, Genetics and Developmental Biology , Paris, France
| | - Florencia di Pietro
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR 3215, Inserm U934, Genetics and Developmental Biology , Paris, France
| | - Yohanns Bellaiche
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR 3215, Inserm U934, Genetics and Developmental Biology , Paris, France
| | - Hans-Arno J Müller
- Division of Developmental Genetics, Institute for Biology, University of Kassel, Kassel, Germany
| | - Jörg Großhans
- Department of Biology, Philipps University, Marburg, Germany
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2
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Mariano NC, Rusin SF, Nasa I, Kettenbach AN. Inducible Protein Degradation as a Strategy to Identify Phosphoprotein Phosphatase 6 Substrates in RAS-Mutant Colorectal Cancer Cells. Mol Cell Proteomics 2023; 22:100614. [PMID: 37392812 PMCID: PMC10400926 DOI: 10.1016/j.mcpro.2023.100614] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 06/13/2023] [Accepted: 06/28/2023] [Indexed: 07/03/2023] Open
Abstract
Protein phosphorylation is an essential regulatory mechanism that controls most cellular processes, including cell cycle progression, cell division, and response to extracellular stimuli, among many others, and is deregulated in many diseases. Protein phosphorylation is coordinated by the opposing activities of protein kinases and protein phosphatases. In eukaryotic cells, most serine/threonine phosphorylation sites are dephosphorylated by members of the Phosphoprotein Phosphatase (PPP) family. However, we only know for a few phosphorylation sites which specific PPP dephosphorylates them. Although natural compounds such as calyculin A and okadaic acid inhibit PPPs at low nanomolar concentrations, no selective chemical PPP inhibitors exist. Here, we demonstrate the utility of endogenous tagging of genomic loci with an auxin-inducible degron (AID) as a strategy to investigate specific PPP signaling. Using Protein Phosphatase 6 (PP6) as an example, we demonstrate how rapidly inducible protein degradation can be employed to identify dephosphorylation sites and elucidate PP6 biology. Using genome editing, we introduce AID-tags into each allele of the PP6 catalytic subunit (PP6c) in DLD-1 cells expressing the auxin receptor Tir1. Upon rapid auxin-induced degradation of PP6c, we perform quantitative mass spectrometry-based proteomics and phosphoproteomics to identify PP6 substrates in mitosis. PP6 is an essential enzyme with conserved roles in mitosis and growth signaling. Consistently, we identify candidate PP6c-dependent dephosphorylation sites on proteins implicated in coordinating the mitotic cell cycle, cytoskeleton, gene expression, and mitogen-activated protein kinase (MAPK) and Hippo signaling. Finally, we demonstrate that PP6c opposes the activation of large tumor suppressor 1 (LATS1) by dephosphorylating Threonine 35 (T35) on Mps One Binder (MOB1), thereby blocking the interaction of MOB1 and LATS1. Our analyses highlight the utility of combining genome engineering, inducible degradation, and multiplexed phosphoproteomics to investigate signaling by individual PPPs on a global level, which is currently limited by the lack of tools for specific interrogation.
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Affiliation(s)
- Natasha C Mariano
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Scott F Rusin
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA; Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA; Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA.
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3
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Mariano NC, Rusin SF, Nasa I, Kettenbach AN. Inducible protein degradation as a strategy to identify Phosphoprotein Phosphatase 6 substrates in RAS-mutant colorectal cancer cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.25.534211. [PMID: 36993243 PMCID: PMC10055397 DOI: 10.1101/2023.03.25.534211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Protein phosphorylation is an essential regulatory mechanism that controls most cellular processes, including cell cycle progression, cell division, and response to extracellular stimuli, among many others, and is deregulated in many diseases. Protein phosphorylation is coordinated by the opposing activities of protein kinases and protein phosphatases. In eukaryotic cells, most serine/threonine phosphorylation sites are dephosphorylated by members of the Phosphoprotein Phosphatase (PPP) family. However, we only know for a few phosphorylation sites which specific PPP dephosphorylates them. Although natural compounds such as calyculin A and okadaic acid inhibit PPPs at low nanomolar concentrations, no selective chemical PPP inhibitors exist. Here, we demonstrate the utility of endogenous tagging of genomic loci with an auxin-inducible degron (AID) as a strategy to investigate specific PPP signaling. Using Protein Phosphatase 6 (PP6) as an example, we demonstrate how rapidly inducible protein degradation can be employed to identify dephosphorylation SITES and elucidate PP6 biology. Using genome editing, we introduce AID-tags into each allele of the PP6 catalytic subunit (PP6c) in DLD-1 cells expressing the auxin receptor Tir1. Upon rapid auxin-induced degradation of PP6c, we perform quantitative mass spectrometry-based proteomics and phosphoproteomics to identify PP6 substrates in mitosis. PP6 is an essential enzyme with conserved roles in mitosis and growth signaling. Consistently, we identify candidate PP6c-dependent phosphorylation sites on proteins implicated in coordinating the mitotic cell cycle, cytoskeleton, gene expression, and mitogen-activated protein kinase (MAPK) and Hippo signaling. Finally, we demonstrate that PP6c opposes the activation of large tumor suppressor 1 (LATS1) by dephosphorylating Threonine 35 (T35) on Mps One Binder (MOB1), thereby blocking the interaction of MOB1 and LATS1. Our analyses highlight the utility of combining genome engineering, inducible degradation, and multiplexed phosphoproteomics to investigate signaling by individual PPPs on a global level, which is currently limited by the lack of tools for specific interrogation.
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4
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Ferree PL, Xing M, Zhang JQ, Di Talia S. Structure-function analysis of Cdc25 Twine degradation at the Drosophila maternal-to-zygotic transition. Fly (Austin) 2022; 16:111-117. [PMID: 35227166 PMCID: PMC8890428 DOI: 10.1080/19336934.2022.2043095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Downregulation of protein phosphatase Cdc25Twine activity is linked to remodelling of the cell cycle during the Drosophila maternal-to-zygotic transition (MZT). Here, we present a structure-function analysis of Cdc25Twine. We use chimeras to show that the N-terminus regions of Cdc25Twine and Cdc25String control their differential degradation dynamics. Deletion of different regions of Cdc25Twine reveals a putative domain involved in and required for its rapid degradation during the MZT. Notably, a very similar domain is present in Cdc25String and deletion of the DNA replication checkpoint results in similar dynamics of degradation of both Cdc25String and Cdc25Twine. Finally, we show that Cdc25Twine degradation is delayed in embryos lacking the left arm of chromosome III. Thus, we propose a model for the differential regulation of Cdc25 at the Drosophila MZT.
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Affiliation(s)
- Patrick L Ferree
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
| | - Maggie Xing
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
| | - Jenny Q Zhang
- Department of Surgery, Alpert Medical School, Brown University, Providence, RI, USA
| | - Stefano Di Talia
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
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5
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Liu B, Zhao H, Wu K, Großhans J. Temporal Gradients Controlling Embryonic Cell Cycle. BIOLOGY 2021; 10:biology10060513. [PMID: 34207742 PMCID: PMC8228447 DOI: 10.3390/biology10060513] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/05/2021] [Accepted: 06/07/2021] [Indexed: 12/17/2022]
Abstract
Simple Summary Embryonic cells sense temporal gradients of regulatory signals to determine whether and when to proceed or remodel the cell cycle. Such a control mechanism is allowed to accurately link the cell cycle with the developmental program, including cell differentiation, morphogenesis, and gene expression. The mid-blastula transition has been a paradigm for timing in early embryogenesis in frog, fish, and fly, among others. It has been argued for decades now if the events associated with the mid-blastula transition, i.e., the onset of zygotic gene expression, remodeling of the cell cycle, and morphological changes, are determined by a control mechanism or by absolute time. Recent studies indicate that multiple independent signals and mechanisms contribute to the timing of these different processes. Here, we focus on the mechanisms for cell cycle remodeling, specifically in Drosophila, which relies on gradual changes of the signal over time. We discuss pathways for checkpoint activation, decay of Cdc25 protein levels, as well as depletion of deoxyribonucleotide metabolites and histone proteins. The gradual changes of these signals are linked to Cdk1 activity by readout mechanisms involving thresholds. Abstract Cell proliferation in early embryos by rapid cell cycles and its abrupt pause after a stereotypic number of divisions present an attractive system to study the timing mechanism in general and its coordination with developmental progression. In animals with large eggs, such as Xenopus, zebrafish, or Drosophila, 11–13 very fast and synchronous cycles are followed by a pause or slowdown of the cell cycle. The stage when the cell cycle is remodeled falls together with changes in cell behavior and activation of the zygotic genome and is often referred to as mid-blastula transition. The number of fast embryonic cell cycles represents a clear and binary readout of timing. Several factors controlling the cell cycle undergo dynamics and gradual changes in activity or concentration and thus may serve as temporal gradients. Recent studies have revealed that the gradual loss of Cdc25 protein, gradual depletion of free deoxyribonucleotide metabolites, or gradual depletion of free histone proteins impinge on Cdk1 activity in a threshold-like manner. In this review, we will highlight with a focus on Drosophila studies our current understanding and recent findings on the generation and readout of these temporal gradients, as well as their position within the regulatory network of the embryonic cell cycle.
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Affiliation(s)
- Boyang Liu
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan 250012, China; (B.L.); (H.Z.); (K.W.)
- Key Laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan 250012, China
- Shandong Key Laboratory of Reproductive Medicine, Jinan 250012, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Jinan 250012, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan 250012, China
| | - Han Zhao
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan 250012, China; (B.L.); (H.Z.); (K.W.)
- Key Laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan 250012, China
- Shandong Key Laboratory of Reproductive Medicine, Jinan 250012, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Jinan 250012, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan 250012, China
| | - Keliang Wu
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan 250012, China; (B.L.); (H.Z.); (K.W.)
- Key Laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan 250012, China
- Shandong Key Laboratory of Reproductive Medicine, Jinan 250012, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Jinan 250012, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan 250012, China
| | - Jörg Großhans
- Department of Biology, Philipps University, 35043 Marburg, Germany
- Correspondence:
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Shindo Y, Amodeo AA. Excess histone H3 is a competitive Chk1 inhibitor that controls cell-cycle remodeling in the early Drosophila embryo. Curr Biol 2021; 31:2633-2642.e6. [PMID: 33848457 DOI: 10.1016/j.cub.2021.03.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 02/08/2021] [Accepted: 03/10/2021] [Indexed: 12/31/2022]
Abstract
The DNA damage checkpoint is crucial to protect genome integrity.1,2 However, the early embryos of many metazoans sacrifice this safeguard to allow for rapid cleavage divisions that are required for speedy development. At the mid-blastula transition (MBT), embryos switch from rapid cleavage divisions to slower, patterned divisions with the addition of gap phases and acquisition of DNA damage checkpoints. The timing of the MBT is dependent on the nuclear-to-cytoplasmic (N/C ratio)3-7 and the activation of the checkpoint kinase, Chk1.8-17 How Chk1 activity is coupled to the N/C ratio has remained poorly understood. Here, we show that dynamic changes in histone H3 availability in response to the increasing N/C ratio control Chk1 activity and thus time the MBT in the Drosophila embryo. We show that excess H3 in the early cycles interferes with cell-cycle slowing independent of chromatin incorporation. We find that the N-terminal tail of H3 acts as a competitive inhibitor of Chk1 in vitro and reduces Chk1 activity in vivo. Using a H3-tail mutant that has reduced Chk1 inhibitor activity, we show that the amount of available Chk1 sites in the H3 pool controls the dynamics of cell-cycle progression. Mathematical modeling quantitatively supports a mechanism where titration of H3 during early cleavage cycles regulates Chk1-dependent cell-cycle slowing. This study defines Chk1 regulation by H3 as a key mechanism that coordinates cell-cycle remodeling with developmental progression.
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Affiliation(s)
- Yuki Shindo
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA; Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA
| | - Amanda A Amodeo
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA; Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA.
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Control of Cell Growth and Proliferation by the Tribbles Pseudokinase: Lessons from Drosophila. Cancers (Basel) 2021; 13:cancers13040883. [PMID: 33672471 PMCID: PMC7923445 DOI: 10.3390/cancers13040883] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/09/2021] [Accepted: 02/14/2021] [Indexed: 12/13/2022] Open
Abstract
Simple Summary Tribbles pseudokinases represent a sub-branch of the CAMK (Ca2+/calmodulin-dependent protein kinase) subfamily and are associated with disease-associated signaling pathways associated with various cancers, including melanoma, lung, liver, and acute leukemia. The ability of this class of molecules to regulate cell proliferation was first recognized in the model organism Drosophila and the fruit fly genetic model and continues to provide insight into the molecular mechanism by which this family of adapter molecules regulates both normal development and disease associated with corruption of their proper regulation and function. Abstract The Tribbles (Trib) family of pseudokinase proteins regulate cell growth, proliferation, and differentiation during normal development and in response to environmental stress. Mutations in human Trib isoforms (Trib1, 2, and 3) have been associated with metabolic disease and linked to leukemia and the formation of solid tumors, including melanomas, hepatomas, and lung cancers. Drosophila Tribbles (Trbl) was the first identified member of this sub-family of pseudokinases and shares a conserved structure and similar functions to bind and direct the degradation of key mediators of cell growth and proliferation. Common Trib targets include Akt kinase (also known as protein kinase B), C/EBP (CAAT/enhancer binding protein) transcription factors, and Cdc25 phosphatases, leading to the notion that Trib family members stand athwart multiple pathways modulating their growth-promoting activities. Recent work using the Drosophila model has provided important insights into novel facets of conserved Tribbles functions in stem cell quiescence, tissue regeneration, metabolism connected to insulin signaling, and tumor formation linked to the Hippo signaling pathway. Here we highlight some of these recent studies and discuss their implications for understanding the complex roles Tribs play in cancers and disease pathologies.
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Liu M, Liu A, Wang J, Zhang Y, Li Y, Su Y, Zhu AJ. Competition between two phosphatases fine-tunes Hedgehog signaling. J Cell Biol 2020; 220:211641. [PMID: 33373452 PMCID: PMC7774589 DOI: 10.1083/jcb.202010078] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/26/2020] [Accepted: 12/02/2020] [Indexed: 12/29/2022] Open
Abstract
Hedgehog (Hh) signaling is essential for embryonic development and adult homeostasis. How its signaling activity is fine-tuned in response to fluctuated Hh gradient is less known. Here, we identify protein phosphatase V (PpV), the catalytic subunit of protein phosphatase 6, as a homeostatic regulator of Hh signaling. PpV is genetically upstream of widerborst (wdb), which encodes a regulatory subunit of PP2A that modulates high-level Hh signaling. We show that PpV negatively regulates Wdb stability independent of phosphatase activity of PpV, by competing with the catalytic subunit of PP2A for Wdb association, leading to Wdb ubiquitination and subsequent proteasomal degradation. Thus, regulated Wdb stability, maintained through competition between two closely related phosphatases, ensures graded Hh signaling. Interestingly, PpV expression is regulated by Hh signaling. Therefore, PpV functions as a Hh activity sensor that regulates Wdb-mediated PP2A activity through feedback mechanisms to maintain Hh signaling homeostasis.
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Affiliation(s)
- Min Liu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China,Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Aiguo Liu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China,Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Jie Wang
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China
| | - Yansong Zhang
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China
| | - Yajuan Li
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China
| | - Ying Su
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China,Correspondence to Ying Su:
| | - Alan Jian Zhu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China,Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China,Alan Jian Zhu:
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Liu B, Gregor I, Müller HA, Großhans J. Fluorescence fluctuation analysis reveals PpV dependent Cdc25 protein dynamics in living embryos. PLoS Genet 2020; 16:e1008735. [PMID: 32251417 PMCID: PMC7162543 DOI: 10.1371/journal.pgen.1008735] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 04/16/2020] [Accepted: 03/25/2020] [Indexed: 12/21/2022] Open
Abstract
The protein phosphatase Cdc25 is a key regulator of the cell cycle by activating Cdk-cyclin complexes. Cdc25 is regulated by its expression levels and post-translational mechanisms. In early Drosophila embryogenesis, Cdc25/Twine drives the fast and synchronous nuclear cycles. A pause in the cell cycle and the remodeling to a more generic cell cycle mode with a gap phase are determined by Twine inactivation and destruction in early interphase 14, in response to zygotic genome activation. Although the pseudokinase Tribbles contributes to the timely degradation of Twine, Twine levels are controlled by additional yet unknown post-translational mechanisms. Here, we apply a non-invasive method based on fluorescence fluctuation analysis (FFA) to record the absolute concentration profiles of Twine with minute-scale resolution in single living embryos. Employing this assay, we found that Protein phosphatase V (PpV), the homologue of the catalytic subunit of human PP6, ensures appropriately low Twine protein levels at the onset of interphase 14. PpV controls directly or indirectly the phosphorylation of Twine at multiple serine and threonine residues as revealed by phosphosite mapping. Mutational analysis confirmed that these sites are involved in control of Twine protein dynamics, and cell cycle remodeling is delayed in a fraction of the phosphosite mutant embryos. Our data reveal a novel mechanism for control of Twine protein levels and their significance for embryonic cell cycle remodeling.
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Affiliation(s)
- Boyang Liu
- Fachbereich Biologie (FB17), Philipps-Universität Marburg, Marburg, Germany
- Institut für Entwicklungsbiochemie, Universitätsmedizin, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Ingo Gregor
- Drittes Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen, Germany
| | - H.-Arno Müller
- Fachgebiet Entwicklungsgenetik, Institut für Biologie, Universität Kassel, Kassel, Germany
| | - Jörg Großhans
- Fachbereich Biologie (FB17), Philipps-Universität Marburg, Marburg, Germany
- Institut für Entwicklungsbiochemie, Universitätsmedizin, Georg-August-Universität Göttingen, Göttingen, Germany
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