scholarly journals α-TubK40me3 is required for neuronal polarization and migration by promoting microtubule formation

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xuan Xie ◽  
Shaogang Wang ◽  
Mingyi Li ◽  
Lei Diao ◽  
Xingyu Pan ◽  
...  
Keyword(s):  
Neuronal Migration ◽  
Neuronal Development ◽  
Critical Role ◽  
Post Translational Modification ◽  
Mouse Cerebral Cortex ◽  
Microtubule Formation ◽  
And Migration ◽  
Neuronal Polarization ◽  
Microtubule Function

AbstractTri-methylation on lysine 40 of α-tubulin (α-TubK40me3) is a recently identified post-translational modification involved in mitosis and cytokinesis. However, knowledge about α-TubK40me3 in microtubule function and post-mitotic cells remains largely incomplete. Here, we report that α-TubK40me3 is required for neuronal polarization and migration by promoting microtubule formation. α-TubK40me3 is enriched in mouse cerebral cortex during embryonic day (E)14 to E16. Knockdown of α-tubulin methyltransferase SETD2 at E14 leads to the defects in neuronal migration, which could be restored by overexpressing either a cytoplasm-localized SETD2 truncation or α-TubK40me3-mimicking mutant. Furthermore, α-TubK40me3 is preferably distributed on polymerized microtubules and potently promotes tubulin nucleation. Downregulation of α-TubK40me3 results in reduced microtubule abundance in neurites and disrupts neuronal polarization, which could be rescued by Taxol. Additionally, α-TubK40me3 is increased after losing α-tubulin K40 acetylation (α-TubK40ac) and largely rescues α-TubK40ac function. This study reveals a critical role of α-TubK40me3 in microtubule formation and neuronal development.

Pathogenesis of Age-related Cataract: a systematic review of proteomic studies

2020 ◽  
Vol 17 ◽  
Author(s):  
Christina Karakosta ◽  
Argyrios Tzamalis ◽  
Michalis Aivaliotis ◽  
Ioannis Tsinopoulos
Keyword(s):  
Systematic Review ◽  
Oxidant Stress ◽  
Critical Role ◽  
Human Lens ◽  
Nuclear Cataract ◽  
Cataract Formation ◽  
Post Translational Modification ◽  
Ability To Act ◽  
Age Related

Background/Objective:: The aim of this systematic review is to identify all the available data on human lens proteomics with a critical role to age-related cataract formation in order to elucidate the physiopathology of the aging lens. Materials and Methods:: We searched on Medline and Cochrane databases. The search generated 328 manuscripts. We included nine original proteomic studies that investigated human cataractous lenses. Results:: Deamidation was the major age-related post-translational modification. There was a significant increase in the amount of αA-crystallin D-isoAsp58 present at all ages, while an increase in the extent of Trp oxidation was apparent in cataract lenses when compared to aged normal lenses. During aging, enzymes with oxidized cysteine at critical sites included GAPDH, glutathione synthase, aldehyde dehydrogenase, sorbitol dehydrogenase, and PARK7. Conclusion:: D-isoAsp in αA crystallin could be associated with the development of age-related cataract in human, by contributing to the denaturation of a crystallin, and decreasing its ability to act as a chaperone. Oxidation of Trp may be associated with nuclear cataract formation in human, while the role of oxidant stress in age-related cataract formation is dominant.

Exosomal miR-214-5p Released from Glioblastoma Cells Modulates Inflammatory Response of Microglia after Lipopolysaccharide Stimulation through Targeting CXCR5

2019 ◽  
Vol 18 (1) ◽  
pp. 78-87 ◽  
Author(s):  
Jian-kai Yang ◽  
Hong-jiang Liu ◽  
Yuanyu Wang ◽  
Chen Li ◽  
Ji-peng Yang ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Critical Role ◽  
Luciferase Reporter ◽  
Clinical Prognosis ◽  
Direct Target ◽  
And Migration ◽  
High Level ◽  
Cxcr5 Expression ◽  
Proliferation And Migration

Background and Objective: Exosomes communicate inter-cellularly and miRNAs play critical roles in this scenario. MiR-214-5p was implicated in multiple tumors with diverse functions uncovered. However, whether miR-214-5p is mechanistically involved in glioblastoma, especially via exosomal pathway, is still elusive. Here we sought to comprehensively address the critical role of exosomal miR-214-5p in glioblastoma (GBM) microenvironment.Methods:The relative expression of miR-214-5p was determined by real-time PCR. Cell viability and migration were measured by MTT and transwell chamber assays, respectively. The secretory cytokines were measured with ELISA kits. The regulatory effect of miR-214-5p on CXCR5 expression was interrogated by luciferase reporter assay. Protein level was analyzed by Western blot.Results:We demonstrated that miR-214-5p was aberrantly overexpressed in GBM and associated with poorer clinical prognosis. High level of miR-214-5p significantly contributed to cell proliferation and migration. GBM-derived exosomal miR-214-5p promoted inflammatory response in primary microglia upon lipopolysaccharide challenge. We further identified CXCR5 as the direct target of miR-214- 5p in this setting.Conclusion:Overexpression of miR-214-5p in GBM modulated the inflammatory response in microglia via exosomal transfer.

scholarly journals Critical role of WNK1 in MYC-dependent early mouse thymocyte development

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Robert Köchl ◽  
Lesley Vanes ◽  
Miriam Llorian Sopena ◽  
Probir Chakravarty ◽  
Harald Hartweger ◽  
...  
Keyword(s):  
Critical Role ◽  
Ion Homeostasis ◽  
Thymocyte Development ◽  
Double Positive ◽  
Mouse Thymocyte ◽  
Proliferation And Differentiation ◽  
Tcr Signals ◽  
And Migration ◽  
Early Mouse

WNK1, a kinase that controls kidney salt homeostasis, also regulates adhesion and migration in CD4+ T cells. Wnk1 is highly expressed in thymocytes, and since migration is important for thymocyte maturation, we investigated a role for WNK1 in mouse thymocyte development. We find that WNK1 is required for the transition of double negative (DN) thymocytes through the β-selection checkpoint and subsequent proliferation and differentiation into double positive (DP) thymocytes. Furthermore, we show that WNK1 negatively regulates LFA1-mediated adhesion and positively regulates CXCL12-induced migration in DN thymocytes. Despite this, migration defects of WNK1-deficient thymocytes do not account for the developmental arrest. Instead, we show that in DN thymocytes WNK1 transduces pre-TCR signals via OXSR1 and STK39 kinases, and the SLC12A2 ion co-transporter that are required for post-transcriptional upregulation of MYC and subsequent proliferation and differentiation into DP thymocytes. Thus, a pathway regulating ion homeostasis is a critical regulator of thymocyte development.

scholarly journals The structure and global distribution of the endoplasmic reticulum network are actively regulated by lysosomes

2020 ◽  
Vol 6 (51) ◽  
pp. eabc7209
Author(s):  
Meng Lu ◽  
Francesca W. van Tartwijk ◽  
Julie Qiaojin Lin ◽  
Wilco Nijenhuis ◽  
Pierre Parutto ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Nutritional Status ◽  
Neuronal Development ◽  
Critical Role ◽  
Causal Link ◽  
Global Distribution ◽  
Growth Defects ◽  
Cellular Environment ◽  
Axonal Extension

The endoplasmic reticulum (ER) comprises morphologically and functionally distinct domains: sheets and interconnected tubules. These domains undergo dynamic reshaping in response to changes in the cellular environment. However, the mechanisms behind this rapid remodeling are largely unknown. Here, we report that ER remodeling is actively driven by lysosomes, following lysosome repositioning in response to changes in nutritional status: The anchorage of lysosomes to ER growth tips is critical for ER tubule elongation and connection. We validate this causal link via the chemo- and optogenetically driven repositioning of lysosomes, which leads to both a redistribution of the ER tubules and a change of its global morphology. Therefore, lysosomes sense metabolic change in the cell and regulate ER tubule distribution accordingly. Dysfunction in this mechanism during axonal extension may lead to axonal growth defects. Our results demonstrate a critical role of lysosome-regulated ER dynamics and reshaping in nutrient responses and neuronal development.

scholarly journals Critical role of Src-Syk-PLCγ2 signaling in megakaryocyte migration and thrombopoiesis

Blood ◽  
2010 ◽  
Vol 116 (5) ◽  
pp. 793-800 ◽  
Author(s):  
Alexandra Mazharian ◽  
Steve G. Thomas ◽  
Tarvinder S. Dhanjal ◽  
Christopher D. Buckley ◽  
Steve P. Watson
Keyword(s):  
Kinase Inhibitor ◽  
Tyrosine Phosphatase ◽  
Critical Role ◽  
Src Family Kinases ◽  
Surface Glycoprotein ◽  
Platelet Recovery ◽  
Glycoprotein Vi ◽  
Syk Kinase ◽  
And Migration

Migration of megakaryocytes (MKs) from the proliferative osteoblastic niche to the capillary-rich vascular niche is essential for proplatelet formation and platelet release. In this study, we explore the role of surface glycoprotein receptors and signaling proteins in regulating MK migration and platelet recovery after immune-induced thrombocytopenia. We show that spreading and migration of mouse primary bone marrow–derived MKs on a fibronectin matrix are abolished by the Src family kinases inhibitor PP1, the Syk kinase inhibitor R406 and the integrin αIIbβ3 antagonist lotrafiban. We also demonstrate that these responses are inhibited in primary phospholipase C γ2 (PLCγ2)–deficient MKs. Conversely, MK spreading and migration were unaltered in the absence of the collagen receptor, the glycoprotein VI–FcRγ-chain complex. We previously reported a correlation between a defect in MK migration and platelet recovery in the absence of platelet endothelial cell adhesion molecule-1 and the tyrosine phosphatase CD148. This correlation also holds for mice deficient in PLCγ2. This study identifies a model in which integrin signaling via Src family kinases and Syk kinase to PLCγ2 is required for MK spreading, migration, and platelet formation.

scholarly journals LncRNA MALAT1 Regulating Lung Carcinoma Progression via the miR-491-5p/UBE2C Axis

2021 ◽  
Vol 27 ◽  
Author(s):  
Juanjuan Dai ◽  
Ning Zhou ◽  
Rui Wu ◽  
Jing Du ◽  
Shuang Miao ◽  
...  
Keyword(s):  
Lung Carcinoma ◽  
Critical Role ◽  
Carcinoma Cells ◽  
Migration Ability ◽  
Invasion And Migration ◽  
Lung Carcinoma Cells ◽  
Lncrna Malat1 ◽  
Anti Cancer ◽  
And Migration

Long noncoding RNAs (lncRNAs) play a critical role in the development of lung carcinoma. The mechanism of MALAT1 in lung carcinoma development is not understood very well. This study aimed to investigate the role of MALAT1 in lung carcinoma progression and the mechanism underlying the role of miR-491-5p in the MALAT1 mediated regulation of UBE2C expression. The results indicated that the expression of MALAT1 was often augmented in lung carcinoma cells. Suppression of MALAT1 blocked the proliferation, invasion and migration ability of cancer cells and inhibited the expression of UBE2C. UBE2C restoration attenuated the MALAT1 knockdown-induced anti-cancer effects. Moreover, UBE2C and MALAT1 were indicated as targets of miR-491-5p and inhibition of miR-491-5p restored the MALAT1 knockdown-induced inhibition of the progression of lung carcinoma. Furthermore, MALAT1 sponged miR-491-5p to upregulate UBE2C expression, causing it to act as a competing endogenous RNA. Collectively, MALAT1 downregulation suppressed lung carcinoma progression by regulating the miR-491-5p/UBE2C axis. These results indicate that MALAT1 could be a molecular target for lung carcinoma treatment and prognosis.

The integrin alphavbeta6 is critical for keratinocyte migration on both its known ligand, fibronectin, and on vitronectin

1998 ◽  
Vol 111 (15) ◽  
pp. 2189-2195 ◽  
Author(s):  
X. Huang ◽  
J. Wu ◽  
S. Spong ◽  
D. Sheppard
Keyword(s):  
Cell Migration ◽  
Tissue Injury ◽  
Critical Role ◽  
Cell Behavior ◽  
Wild Type ◽  
Migration Assays ◽  
And Migration ◽  
Hepatocyte Growth

The integrin alphavbeta6 is expressed on a variety of epithelial cells during dynamic processes including organogenesis, tissue injury and malignant transformation. However, because of the lack of tools to specifically inhibit the function of this integrin, little is known about its effects on cell behavior. To directly examine the role of this integrin in cell migration, we used keratinocytes derived from wild-type mice or mice expressing a null mutation in the beta6 subunit (beta6-/-) to perform migration assays in vitro. Migration on the known alphavbeta6 ligand, fibronectin was reduced in keratinocytes from beta6-/- mice. Interestingly, keratinocytes from beta6-/- mice also demonstrated markedly reduced migration on vitronectin, a protein not previously known to be a ligand for alphavbeta6. An anti-alphavbeta6 monoclonal antibody 10D5, generated by immunization of beta6-/- mice with murine keratinocytes, inhibited adhesion and migration of wild-type keratinocyte on both vitronectin and fibronectin to levels similar to those seen with keratinocytes from beta6-/- mice. alphavbeta6-mediated migration on both ligands was dramatically augmented by treatment with phorbol myrisate acetate (PMA) or with hepatocyte growth factor, and augmentation of migration by either stimulus could be abolished by the PKC inhibitor GF109203X, suggesting a critical role for PKC in enhancement of alphavbeta6-mediated cell migration.

Role of the small GTPase Rap1 for integrin activity regulation in endothelial cells and angiogenesis

Blood ◽  
2009 ◽  
Vol 113 (2) ◽  
pp. 488-497 ◽  
Author(s):  
Guillaume Carmona ◽  
Stephan Göttig ◽  
Alessia Orlandi ◽  
Jürgen Scheele ◽  
Tobias Bäuerle ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Umbilical Vein ◽  
Critical Role ◽  
Limb Ischemia ◽  
Small Gtpase ◽  
And Migration ◽  
Umbilical Vein Endothelial Cells ◽  
Endothelial Growth Factor

Abstract Ras-associated protein 1 (Rap1), a small GTPase, attracted attention because of its involvement in several aspects of cell adhesion, including integrin- and cadherin-mediated adhesion. Yet, the role of Rap1 genes and of Rap1 effectors for angiogenesis has not been investigated. Human umbilical vein endothelial cells (HUVECs) express Rap1a and Rap1b mRNA. To determine the contribution of Rap1 activity for angiogenesis, we overexpressed Rap1GAP1, a GTPase-activating protein that inhibits Rap1 activity. Overexpression of Rap1GAP1 significantly blocked angiogenic sprouting and tube-forming activity of HUVECs as well as migration and integrin-dependent adhesion. Silencing of Rap1a, Rap1b, or both significantly blocked HUVECs sprouting under basal and basic fibroblast growth factor-stimulated conditions and reduced HUVEC migration and integrin-dependent adhesion. We found that Rap1a and Rap1b are essential for the conformational activation of β1-integrins in endothelial cells. Furthermore, silencing of Rap1a and Rap1b prevented phosphorylation of tyrosine 397 in focal adhesion kinase (FAK) and vascular endothelial growth factor-induced Akt1-activation. Rap1a−/−-deficient and Rap1a+/− heterozygote mice displayed reduced neovascularization after hind limb ischemia compared with wild-type mice. Silencing of RAPL significantly blocked the Rap1-induced sprouting of HUVECs, suggesting that the angiogenic activity of Rap1 is partly mediated by RAPL. Our data demonstrate a critical role of Rap1 in the regulation of β1-integrin affinity, adhesion, and migration in endothelial cells and in postnatal neovascularization.

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