Carboxypeptidase E Independently Changes Microtubule Glutamylation, Dendritic Branching, and Neuronal Migration

Neuronal migration and dendritogenesis are dependent on dynamic changes to the microtubule (MT) network. Among various factors that regulate MT dynamics and stability, post-translational modifications (PTMs) of MTs play a critical role in conferring specificity of regulatory protein binding to MTs. Thus, it is important to understand the regulation of PTMs during brain development as multiple developmental processes are dependent on MTs. In this study, we identified that carboxypeptidase E (CPE) changes tubulin polyglutamylation, a major PTM in the brain, and we examine the impact of CPE-mediated changes to polyglutamylation on cortical neuron migration and dendrite morphology. We show, for the first time, that overexpression of CPE increases the level of polyglutamylated α-tubulin while knockdown decreases the level of polyglutamylation. We also demonstrate that CPE-mediated changes to polyglutamylation are dependent on the CPE zinc-binding motif and that this motif is necessary for CPE action on p150Glued localization. However, overexpression of a CPE mutant that does not increase MT glutamylation mimics the effects of overexpression of wild type CPE on dendrite branching. Furthermore, although overexpression of wild type CPE does not alter cortical neuron migration, overexpression of the mutant may act in a dominant-negative manner as it decreases the number of neurons that reach the cortical plate (CP), as we previously reported for CPE knockdown. Overall, our data suggest that CPE changes MT glutamylation and redistribution of p150Glued and that this function of CPE is independent of its role in shaping dendrite development but plays a partial role in regulating cortical neuron migration.

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Cortical Neuron Migration and Dendrite Morphology are Regulated by Carboxypeptidase E

Cerebral Cortex ◽

10.1093/cercor/bhy155 ◽

2018 ◽

Vol 29 (7) ◽

pp. 2890-2903 ◽

Cited By ~ 2

Author(s):

Chen Liang ◽

Damien Carrel ◽

Anton Omelchenko ◽

Hyuck Kim ◽

Aashini Patel ◽

...

Keyword(s):

Brain Development ◽

Cortical Neuron ◽

Neuronal Migration ◽

Brain Function ◽

Neurocognitive Disorders ◽

Dendrite Morphology ◽

Neuron Migration ◽

Binding Partner ◽

Carboxypeptidase E ◽

Early Brain Development

Abstract Higher brain function relies on proper development of the cerebral cortex, including correct positioning of neurons and dendrite morphology. Disruptions in these processes may result in various neurocognitive disorders. Mutations in the CPE gene, which encodes carboxypeptidase E (CPE), have been linked to depression and intellectual disability. However, it remains unclear whether CPE is involved in early brain development and in turn contributes to the pathophysiology of neurocognitive disorders. Here, we investigate the effects of CPE knockdown on early brain development and explore the functional significance of the interaction between CPE and its binding partner p150Glued. We demonstrate that CPE is required for cortical neuron migration and dendrite arborization. Furthermore, we show that expression of CPE-C10 redistributes p150Glued from the centrosome and that disruption of CPE interaction with p150Glued leads to abnormal neuronal migration and dendrite morphology, suggesting that a complex between CPE and p150Glued is necessary for proper neurodevelopment.

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146. MACROPHAGES ARE ESSENTIAL FOR MAINTENANCE OF EARLY PREGNANCY THROUGH REGULATION OF CORPUS LUTEUM FUNCTION

Reproduction Fertility and Development ◽

10.1071/srb09abs146 ◽

2009 ◽

Vol 21 (9) ◽

pp. 64

Author(s):

A. S. Care ◽

M. J. Jasper ◽

W. V. Ingman ◽

S. A. Robertson

Keyword(s):

Corpus Luteum ◽

Early Pregnancy ◽

Ovarian Tissue ◽

Critical Role ◽

Fetal Loss ◽

Wild Type ◽

Tissue Remodelling ◽

Serum Progesterone ◽

Implantation Sites ◽

The Impact

Macrophages are abundant within the ovary, and have been identified in the corpus luteum (CL) of most species studied, including in rodents and human. Through their secretory products, macrophages are thought to be involved in ovarian tissue remodelling, including luteinization, and in regulating steroidogenesis [1, 2]. Macrophages co-cultured with granulosa or luteal cells act to stimulate progesterone secretion [3]. To determine the impact of macrophage ablation during early pregnancy, we utilised the macrophage specific CD11b-DTR diphtheria toxin receptor (DTR) transgenic mouse to cause transient systemic ablation of macrophages via the administration of DT (25 ng/g). The effects of macrophage ablation during the pre-implantation phase of pregnancy were evaluated and implantation sites were counted. Ablation of macrophages on day 1 pc (n=13 wild-type; n=9 CD11b-DTR) or day 4 pc (n=6 CD11b-DTR; n=9 wild-type) caused complete pregnancy loss in all DT-treated CD11b-DTR mice, while wild-type mice maintained viable pregnancies [mean ± SEM implantation sites = 5.0 ± 1.4 (day 1 treated), and 6.0 ± 1.9 (day 4 treated)]. Serum progesterone was analysed 24 h following macrophage ablation. A single DT injection on day 3 pc significantly reduced serum progesterone (P4) levels [n=7 wild-type P4 (ng/ml)= 29.6 ± 3.3; n=8 CD11b-DTR = 11.1 ± 2.1]. The administration of exogenous P4 (2 mg) on each of day 4-7 pc prevented fetal loss in DT-treated CD11b-DTR mice (n=6; implantation sites = 7.8 ± 1.6), while no pregnancies remained viable in DT-treated mice administered vehicle only (n=9). In conclusion, luteal insufficiency appears to be the cause of pregnancy failure following macrophage ablation. These data indicate a critical role for macrophages in corpus luteum function in early pregnancy.

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Dynein activating adaptor BICD2 controls radial migration of upper-layer cortical neurons in vivo

Acta Neuropathologica Communications ◽

10.1186/s40478-019-0827-y ◽

2019 ◽

Vol 7 (1) ◽

Cited By ~ 3

Author(s):

Lena Will ◽

Sybren Portegies ◽

Jasper van Schelt ◽

Merel van Luyk ◽

Dick Jaarsma ◽

...

Keyword(s):

Cortical Neuron ◽

Cortical Neurons ◽

Cortical Development ◽

Adaptor Protein ◽

Cortical Plate ◽

Neuron Migration ◽

Knock Out ◽

Radial Migration

Abstract For the proper organization of the six-layered mammalian neocortex it is required that neurons migrate radially from their place of birth towards their designated destination. The molecular machinery underlying this neuronal migration is still poorly understood. The dynein-adaptor protein BICD2 is associated with a spectrum of human neurological diseases, including malformations of cortical development. Previous studies have shown that knockdown of BICD2 interferes with interkinetic nuclear migration in radial glial progenitor cells, and that Bicd2-deficient mice display an altered laminar organization of the cerebellum and the neocortex. However, the precise in vivo role of BICD2 in neocortical development remains unclear. By comparing cell-type specific conditional Bicd2 knock-out mice, we found that radial migration in the cortex predominantly depends on BICD2 function in post-mitotic neurons. Neuron-specific Bicd2 cKO mice showed severely impaired radial migration of late-born upper-layer neurons. BICD2 depletion in cortical neurons interfered with proper Golgi organization, and neuronal maturation and survival of cortical plate neurons. Single-neuron labeling revealed a specific role of BICD2 in bipolar locomotion. Rescue experiments with wildtype and disease-related mutant BICD2 constructs revealed that a point-mutation in the RAB6/RANBP2-binding-domain, associated with cortical malformation in patients, fails to restore proper cortical neuron migration. Together, these findings demonstrate a novel, cell-intrinsic role of BICD2 in cortical neuron migration in vivo and provide new insights into BICD2-dependent dynein-mediated functions during cortical development.

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Structural analysis of phosphorylation-associated interactions of MCC to Scribble PDZ domains

10.1101/501064 ◽

2018 ◽

Author(s):

Sofia Caria ◽

Bryce Z Stewart ◽

Patrick O Humbert ◽

Marc Kvansakul

Keyword(s):

Cell Polarity ◽

Posttranslational Modifications ◽

Adaptor Protein ◽

Structural Basis ◽

Binding Motif ◽

Pdz Domains ◽

Wild Type ◽

Ligand Interactions ◽

Direct Cell ◽

The Impact

Scribble is a crucial adaptor protein that plays a pivotal role during establishment and control of cell polarity, impacting many physiological processes ranging from cell migration to immunity and organization of tissue architecture. Scribble harbors a leucine-rich repeat domain and four PDZ domains, which mediate most of Scribbles interactions with other proteins. It has become increasingly clear that posttranslational modifications substantially impact Scribble-ligand interactions, with phosphorylation being a major modulator of binding to Scribble. To better understand how Scribble PDZ domains direct cell polarity signalling and how phosphorylation impacts this process, we investigated Scribble interactions with MCC (mutated in colorectal cancer). We systematically evaluated the ability of all four individual Scribble PDZ domains to bind the PDZ-binding motif (PBM) of wild-type MCC as well as MCC phosphorylated at the -1 Ser position. We show that Scribble PDZ1 and PDZ3 are the major interactors with MCC, and that modifications to Ser at the -1 position in the MCC PBM only has a modest effect on binding to Scribble PDZ domains. We then examined the structural basis for these observations by determining the crystal structures of Scribble PDZ1 domain bound to both the wild-type MCC PBM as well as phosphorylated MCC. Our structures indicated that phospho-Ser at the -1 position in MCC is not involved in major contacts with Scribble PDZ1, and in conjunction with our affinity measurements suggest that the impact of phosphorylation at the -1 position of MCC extends beyond a simple modulation of the affinity for Scribble PDZ domains.

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Defective Extraembryonic Angiogenesis in Mice Lacking LBP-1a, a Member of the grainyhead Family of Transcription Factors

Molecular and Cellular Biology ◽

10.1128/mcb.24.16.7113-7129.2004 ◽

2004 ◽

Vol 24 (16) ◽

pp. 7113-7129 ◽

Cited By ~ 22

Author(s):

Vishwas Parekh ◽

Amy McEwen ◽

Virginia Barbour ◽

Yutaka Takahashi ◽

Jerold E. Rehg ◽

...

Keyword(s):

Intrauterine Growth Retardation ◽

Critical Role ◽

Binding Motif ◽

Structural Genes ◽

Wild Type ◽

Transcription Factor Family ◽

Differentiation Markers ◽

Trophoblast Differentiation ◽

Intrauterine Growth ◽

Normal Placenta

ABSTRACT LBP-1a and CP2 are ubiquitously expressed members of the grainyhead transcription factor family, sharing significant sequence homology, a common DNA binding motif, and modulating a range of key regulatory and structural genes. We have reported previously that CP2-null mice are viable with no obvious abnormality. LBP-1a provides redundant function in this context. We show here that mice lacking LBP-1a expression develop intrauterine growth retardation at embryonic day 10.5, culminating in death 1 day later. No focal intraembryonic cause for this CP2-independent defect is evident. In contrast, a significant reduction in the thickness of the labyrinthine layer of the placenta is observed in LBP-1a−/− animals. However, expression of trophoblast differentiation markers is unperturbed in this context, and complementation studies utilizing tetraploid wild-type cells failed to rescue or ameliorate the LBP-1a−/− phenotype, excluding a primary trophoblast defect. An explanation for these observations is provided by the prominent angiogenic defect observed in the mutant placentas. LBP-1a−/− allantoic blood vessels fail to penetrate deeply and branch into the complex embryonic vasculature characteristic of the normal placenta. Interestingly, a similar defect in angiogenesis is observed in the yolk sac vasculature, primary endothelial cell-lined capillary tubes, although present, failed to connect into a characteristic intricate vascular network. Collectively, these results demonstrate that LBP-1a plays a critical role in the regulation of extraembryonic angiogenesis.

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The Laryngeal Epithelium in Reflux

Perspectives on Voice and Voice Disorders ◽

10.1044/vvd21.3.112 ◽

2011 ◽

Vol 21 (3) ◽

pp. 112-117 ◽

Cited By ~ 2

Author(s):

Elizabeth Erickson-Levendoski ◽

Mahalakshmi Sivasankar

Keyword(s):

Laryngopharyngeal Reflux ◽

Critical Role ◽

Structure And Function ◽

Laryngeal Disease ◽

Health And Disease ◽

And Function ◽

The Impact

The epithelium plays a critical role in the maintenance of laryngeal health. This is evident in that laryngeal disease may result when the integrity of the epithelium is compromised by insults such as laryngopharyngeal reflux. In this article, we will review the structure and function of the laryngeal epithelium and summarize the impact of laryngopharyngeal reflux on the epithelium. Research investigating the ramifications of reflux on the epithelium has improved our understanding of laryngeal disease associated with laryngopharyngeal reflux. It further highlights the need for continued research on the laryngeal epithelium in health and disease.

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Subtle Impact of Akt1 and Akt3 on Exploratory Behavior in Gene Targeted Mice

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000218 ◽

2015 ◽

Vol 223 (3) ◽

pp. 173-180 ◽

Cited By ~ 1

Author(s):

Christina Leibrock ◽

Michael Hierlmeier ◽

Undine E. Lang ◽

Florian Lang

Keyword(s):

Forced Swimming Test ◽

Open Field Test ◽

Wild Type ◽

Average Speed ◽

Closed Area ◽

Light Area ◽

Swimming Test ◽

The Impact ◽

Center Area ◽

Dark Transition

Abstract. The present study explored the impact of Akt1 and Akt3 on behavior. Akt1 (akt1-/-) and Akt3 (akt3-/-) knockout mice were compared to wild type (wt) mice. The akt1-/- mice, akt3-/- mice, and wt mice were similar in most parameters of the open-field test. However, the distance traveled in the center area was slightly but significantly less in akt3-/- mice than in wt mice. In the light/dark transition test akt1-/- mice had significantly lower values than wt mice and akt3-/- mice for distance traveled, number of rearings, rearing time in the light area, as well as time spent and distance traveled in the entrance area. They were significantly different from akt3-/- mice in the distance traveled, visits, number of rearings, rearing time in the light area, as well as time spent, distance traveled, number of rearings, and rearing time in the entrance area. In the O-maze the time spent, and the visits to open arms, as well as the number of protected and unprotected headdips were significantly less in akt1-/- mice than in wt mice, whereas the time spent in closed arms was significantly more in akt1-/- mice than in wt mice. Protected and unprotected headdips were significantly less in akt3-/- mice than in wt mice. In closed area, akt3-/- mice traveled a significantly larger distance at larger average speed than akt1-/- mice. No differences were observed between akt1-/- mice, akt3-/- mice and wt-type mice in the time of floating during the forced swimming test. In conclusion, akt1-/- mice and less so akt3-/ mice display subtle changes in behavior.

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The lung–gut axis during viral respiratory infections: the impact of gut dysbiosis on secondary disease outcomes

Mucosal Immunology ◽

10.1038/s41385-020-00361-8 ◽

2021 ◽

Author(s):

Valentin Sencio ◽

Marina Gomes Machado ◽

François Trottein

Keyword(s):

Gut Microbiota ◽

Bacterial Infections ◽

Respiratory Infections ◽

Critical Role ◽

Good Health ◽

Disease Outcomes ◽

And Function ◽

Viral Respiratory Infections ◽

The Impact ◽

Viral Respiratory

AbstractBacteria that colonize the human gastrointestinal tract are essential for good health. The gut microbiota has a critical role in pulmonary immunity and host’s defense against viral respiratory infections. The gut microbiota’s composition and function can be profoundly affected in many disease settings, including acute infections, and these changes can aggravate the severity of the disease. Here, we discuss mechanisms by which the gut microbiota arms the lung to control viral respiratory infections. We summarize the impact of viral respiratory infections on the gut microbiota and discuss the potential mechanisms leading to alterations of gut microbiota’s composition and functions. We also discuss the effects of gut microbial imbalance on disease outcomes, including gastrointestinal disorders and secondary bacterial infections. Lastly, we discuss the potential role of the lung–gut axis in coronavirus disease 2019.

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Methionine Diet Evoked Hyperhomocysteinemia Causes Hippocampal Alterations, Metabolomics Plasma Changes and Behavioral Pattern in Wild Type Rats

International Journal of Molecular Sciences ◽

10.3390/ijms22094961 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4961

Author(s):

Maria Kovalska ◽

Eva Baranovicova ◽

Dagmar Kalenska ◽

Anna Tomascova ◽

Marian Adamkov ◽

...

Keyword(s):

Morphological Changes ◽

Brain Area ◽

Critical Role ◽

Cerebrovascular Diseases ◽

Behavioral Pattern ◽

Cell Physiology ◽

Male Wistar Rats ◽

High Level ◽

Hippocampal Alterations ◽

The Impact

L-methionine, an essential amino acid, plays a critical role in cell physiology. High intake and/or dysregulation in methionine (Met) metabolism results in accumulation of its intermediate(s) or breakdown products in plasma, including homocysteine (Hcy). High level of Hcy in plasma, hyperhomocysteinemia (hHcy), is considered to be an independent risk factor for cerebrovascular diseases, stroke and dementias. To evoke a mild hHcy in adult male Wistar rats we used an enriched Met diet at a dose of 2 g/kg of animal weight/day in duration of 4 weeks. The study contributes to the exploration of the impact of Met enriched diet inducing mild hHcy on nervous tissue by detecting the histo-morphological, metabolomic and behavioural alterations. We found an altered plasma metabolomic profile, modified spatial and learning memory acquisition as well as remarkable histo-morphological changes such as a decrease in neurons’ vitality, alterations in the morphology of neurons in the selective vulnerable hippocampal CA 1 area of animals treated with Met enriched diet. Results of these approaches suggest that the mild hHcy alters plasma metabolome and behavioural and histo-morphological patterns in rats, likely due to the potential Met induced changes in “methylation index” of hippocampal brain area, which eventually aggravates the noxious effect of high methionine intake.

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NLRP7 Promotes Choriocarcinoma Growth and Progression through the Establishment of an Immunosuppressive Microenvironment

Cancers ◽

10.3390/cancers13122999 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2999

Author(s):

Deborah Reynaud ◽

Roland Abi Nahed ◽

Nicolas Lemaitre ◽

Pierre-Adrien Bolze ◽

Wael Traboulsi ◽

...

Keyword(s):

Immune Response ◽

Tumor Cells ◽

Major Gene ◽

Critical Role ◽

Orthotopic Model ◽

Independent Manner ◽

Maternal Immune Response ◽

The Impact

The inflammatory gene NLRP7 is the major gene responsible for recurrent complete hydatidiform moles (CHM), an abnormal pregnancy that can develop into gestational choriocarcinoma (CC). However, the role of NLRP7 in the development and immune tolerance of CC has not been investigated. Three approaches were employed to define the role of NLRP7 in CC development: (i) a clinical study that analyzed human placenta and sera collected from women with normal pregnancies, CHM or CC; (ii) an in vitro study that investigated the impact of NLRP7 knockdown on tumor growth and organization; and (iii) an in vivo study that used two CC mouse models, including an orthotopic model. NLRP7 and circulating inflammatory cytokines were upregulated in tumor cells and in CHM and CC. In tumor cells, NLRP7 functions in an inflammasome-independent manner and promoted their proliferation and 3D organization. Gravid mice placentas injected with CC cells invalidated for NLRP7, exhibited higher maternal immune response, developed smaller tumors, and displayed less metastases. Our data characterized the critical role of NLRP7 in CC and provided evidence of its contribution to the development of an immunosuppressive maternal microenvironment that not only downregulates the maternal immune response but also fosters the growth and progression of CC.

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