Downloaded 257 times
Uploaded byElsa von Licy
Cell junctions 2013
This document discusses cell junctions and their roles in various biological processes. It defines the main types of cell junctions, including tight junctions, gap junctions, focal adhesions, adherens junctions, and desmosomes. It provides examples of how cell junction gene expression changes during epithelial-to-mesenchymal transition, stem cell differentiation, cancer, atopic dermatitis, and the effects of probiotic bacteria on intestinal barriers. PCR array tools are presented as ways to study cell junctions and related pathways at the gene expression level to better understand their functions in normal and disease states.
In this document
Powered by AI
Introduction to the cell junctions topic by Dr. George J. Quellhorst, emphasizing their significance in cell biology.
Outline of presentation topics such as definitions, types of cell junctions, and their roles in diseases.
Cell junctions are multi-protein complexes important for cell adhesion, communication, and force transduction.
Overview of main cell junction types: Tight junctions, Gap junctions, Focal Adhesions, and their specific functions.
Tight junctions prevent molecule passage, located in areas like the blood-brain barrier and involved in disease processes.
Gap junctions facilitate cell communication in diverse tissues and their role in processes like immune responses.
Details on connexin types in cardiac cells and their relevance in heart disease.
These junctions link cells to the extracellular matrix, aiding in cell survival and migration.
Roles of adherens junctions and desmosomes in maintaining cell adhesion and tissue integrity.
EMT alters cell junctions, contributing to cancer metastasis, with changes in gene expression.
Changes in gene expression related to different types of junctions influenced by EMT.
Atopic dermatitis is associated with tight junction issues, affecting barrier function.
Probiotic bacteria like Lactobacillus plantarum can improve tight junctions and intestinal barrier function.
Gene expression changes in junctions influence differentiation of stem cells into specific lineages.
Summary of cell junctions' functions across cell types and their importance in various biological processes.
Introduction to RT2 Profiler PCR Arrays available for studying various cell junctions.
Promotional offer for two free PCR arrays with purchase, inviting questions about research support.
Closing remarks and invitation for questions regarding cell junctions and their biological importance.
More Related Content
Similar to Cell junctions 2013
Cell junctions 2013
- 1. What’s Your CellLine Saying? Cell Junctions & Cell Biology George J. Quellhorst, Jr., PhD Associate Director, R&D Biological Content Development . . . Sample & Assay Technologies
- 2. Topics to beDiscussed General Definition of Cell Junctions Specific Cell Junctions Who, What, When, Where, and Why Examples of Gene Expression Changes Cancer Atopic Dermatitis Probiotics Intestinal Barrier Stem Cell Differentiation -2- Sample & Assay Technologies
- 3. Cell Junctions Definition Multi-proteinComplexes Connect Neighboring Cells or Cells To ECM Extracellularly Connect To Cytoskeleton Intracellularly Especially Important in Epithelial Tissue General Function Cellular Adhesion & Cellular Communication Transduction of Mechanical Force Molecular Biology of the Cell. 4th edition. Alberts B, Johnson A, Lewis J, et al. New York: Garland Science; 2002. -3- Sample & Assay Technologies
- 4. Cell Junctions Types TightJunctions (Occluding Junctions) Seal adjacent epithelial cells together Prevent passage of most dissolved molecules, membrane-bound lipids and proteins between apical and basolateral surfaces Gap Junctions (Communicating Junctions) Allow adjacent cell communication; pass ions & small molecules between cytoplasms Focal Adhesions & Hemidesmosomes (Anchoring Junctions, Actin & Intermediate Filament Attachment Sites) Form around integrin-mediated cell–ECM contacts Focal adhesions connect integrins to actin filaments Hemidesmosomes connect integrins to intermediate filaments Adherens Junctions & Desmosomes (Anchoring Junctions, Actin & Intermediate Filament Attachment Sites) Form around cadherin-mediated cell–cell contacts Adherens junctions connect cadherins to actin filaments Desmosomes connect cadherins to intermediate filaments -4- Sample & Assay Technologies
- 5. Tight Junctions Location Blood–Brain Barrier BloodVessels Intestines Nephrons Skin Normal Processes Immune Cell Extravasation/Diapedesis Intestinal Absorption Diseases Inflammatory Bowel Disease Epithelial-to-Mesenchymal Transition (EMT) Components Claudins & Occludin Actinins & Catenins Protein Kinases & G-Proteins -5- http://en.wikipedia.org/ Cell Surface Receptors Intracellular Adaptor Proteins Cytoskeleton Regulation Sample & Assay Technologies
- 6. Gap Junctions Location Cardiomyocytes Keratinocytes Astrocytes Endothelial Cells SmoothMuscle Cells Normal Processes Excitable Cell Contraction, Neural Activity Cellular Growth & Differentiation, Embryonic Development http://en.wikipedia.org/ Immune Responses, Tissue Homeostasis, Metabolic Transport Diseases Cardiovascular Disease Neurological Disorders Developmental Abnormalities Components Innexins & Connexins Dimerize to form channels Receptors, Protein Kinases & G-Proteins Regulate Connexins -6- Sample & Assay Technologies
- 7. Gap Junction andConnexin Expression in the Heart Cx40 = GJA5 Cx43 = GJA1 Cx45 = GJC1 Severs NJ, Bruce AF, Dupont E, Rothery S. (2008) Remodelling of gap junctions and connexin expression in diseased myocardium. Cardiovasc Res. 80:9. -7- Sample & Assay Technologies
- 8. Focal Adhesions &Hemidesmosomes Desmosome Location Epithelial Cells Normal Processes Angiogenesis Anchorage-Dependent Cell Survival Cell Cycle Cell Migration Wound Healing Diseases Fibrosis Epithelial-to-Mesenchymal Transition (EMT) Components Integrins http://en.wikipedia.org/ Actin Filaments & Keratin-Based Intermediate Filaments Focal Adhesion Kinase (PTK2 or FAK) & Integrin-Linked Kinase (ILK) PI-3-Kinase/AKT & G-Protein Signaling Filamin, Vinculin & Talin -8- Sample & Assay Technologies
- 9. Adherens Junctions &Desmosomes Location Adhesion belts linking adjacent epithelial cells Focal contacts on lower surface of cultured fibroblasts Normal Processes Intestinal Absorption Keratinization Vascular Biology WNT-Dependent Development Diseases Cardiomyopathies Fibroproliferative Disorders Polycystic Kidney Disease Epithelial-To-Mesenchymal Transition (EMT) Components http://en.wikipedia.org/ Cadherins Actin Filaments & Intermediate (Keratin & Desmin) Filaments Desmocollins, Desmogleins, Nectins, & Notch Proteins Catenins, Protein Kinases, G-Proteins (Cytoskeleton Regulation) -9- Sample & Assay Technologies
- 10. Epithelial-to-Mesenchymal Transition (EMT) AltersCell Junctions EMT = Process whereby cancer cells leave primary tumor into circulation Lose epithelial traits and gain mesenchymal stem cell markers Reverse process at metastatic site hTERT-immortalized primary prostate cancer cells Versus Same cells selected for loss of contact inhibition Morphology and expression markers consistent with EMT Migration and invasion assays also consistent Agilent Whole Human Genome Microarray Genes Fold Change p-value Genes Gap Junction Fold Change p-value Tight Junction GJB3 -87 7.30E-10 CLDN7 -20 1.20E-05 GJB6 -39 5.80E-06 OCLN -4 4.80E-03 GJB5 -36 6.00E-10 CLDN1 -3 2.50E-02 GJB2 -20 7.70E-07 CLDN4 -2 9.60E-04 GJB4 -17 3.80E-07 Ke X.S. et al. (2008) Epithelial to mesenchymal transition of a primary prostate cell line with switches of cell adhesion modules but without malignant transformation. PLoS One. 3:e3368. - 10 - Sample & Assay Technologies
- 11. Epithelial-to-Mesenchymal Transition (EMT) AltersCell Junctions Genes Fold Change p-value Genes Desmosome Fold Change p-value Desmosome DSG3 -93 7.00E-07 DSC3 -6 7.70E-07 PPL -39 4.90E-05 PKP2 -6 4.00E-07 PKP3 -19 5.00E-09 DSG2 -2 1.90E-03 JUP -18 2.90E-07 DSP -9 1.50E-03 Hemidesmosome DSC2 -8 2.70E-07 DST -37 5.10E-08 PKP1 -7 7.20E-06 ITGB4 -11 2.50E-05 Adherens Junction Focal Adhesion CDH3 -120 6.50E-08 ITGB4 -11 2.50E-05 CDH1 -24 6.90E-08 ITGB6 -6 2.60E-06 CDH2 -3 1.00E-08 CAV1 -3 9.80E-04 CTNNB1 -3 8.00E-04 PTK2 -2 1.70E-06 CTNND1 -2 1.70E-03 PARVA 2 2.80E-03 4 2.50E-06 ITGA11 4 4.60E-09 PVRL1 Ke X.S. et al. (2008) Epithelial to mesenchymal transition of a primary prostate cell line with switches of cell adhesion modules but without malignant transformation. PLoS One. 3:e3368. - 11 - Sample & Assay Technologies
- 12. Tight Junction DefectsExist in Atopic Dermatitis Atopic Dermatitis (AD) OR Psoriasis (PS) Versus Non-Atopic (NA) Illumina’s BeadChips Correlation with impaired tight junction function Trans-Epithelial Electrical Resistance (TEER) Also by CLDN1 knockdown which also increases keratinocyte proliferation De Benedetto A et al. (2011) Tight junction defects in patients with atopic dermatitis. J Allergy Clin Immunol. 127:773. - 12 - Sample & Assay Technologies
- 13. Pro-Biotic Bacteria ImproveHealthy Intestinal Barriers Caco-2 treatment of pro-biotic bacteria Lactobacillus plantarum Increases intestinal barrier function (TEER) Increases tight junction gene expression Anderson RC et al. (2010) Lactobacillus plantarum MB452 enhances the function of the intestinal barrier by increasing the expression levels of genes involved in tight junction formation. BMC Microbiol. 10:316. - 13 - Sample & Assay Technologies
- 14. Cell Junction GeneExpression Changes Drive ESC Differentiation to Endothelial & Hematopoietic Cells Expression changes from ESC to mesoderm to terminal differentiation in all junctions Knockdown CDH1, GJA1, TJP1 favors endothelial over hematopoietic cells Gene E-cad Cldn4 Cldn6 Cx31 Cx43 Cx45 ZO-1 ZO-2 ICAM Integrin B4 Symbol Cdh1 Cldn4 Cldn6 Gjb3 Gja1 Gjc1 Tjp1 Tjp2 Icam1 Itgb4 Junction Adherens Tight Tight Gap Gap Gap Tight, Gap, Adherens Tight, Gap Tight Focal Adhesion CDH1 GJA1 TJP1 TJP2 T (brachyury) FLT3/KDR TAL1 Stankovich BL, Aguayo E, Barragan F, Sharma A, and Pallavicini MG. (2011) Differential adhesion molecule expression during murine embryonic stem cell commitment to the hematopoietic and endothelial lineages. PLoS One 6:e23810. - 14 - Sample & Assay Technologies
- 15. Summary & Conclusions Celljunctions present in many cell types Some cell types predominately contain one junction type – Cardiomyocytes: Gap Junctions Some cell types contain multiple junction types – Epithelial Cells: Tight Junctions, Focal Adhesions & Adherens Junctions Play role in normal biological and pathophysiological processes Differentiation Cancer Epithelial Layer Function Usually studied by traditional cell biological techniques Immunofluorescence, Electron Microscopy Can also be studied at the gene expression level Permits analysis of more component genes at the same time - 15 - Sample & Assay Technologies
- 16. Available RT2 ProfilerPCR Arrays Cell Junction PathwayFinder™ Tight Junctions Gap Junctions Focal Adhesions Adherens Junctions Extracellular Matrix & Cell Adhesion Molecules Cytoskeleton Regulators Primary Cilia Cell Motility Many other areas of biological research … - 16 - Sample & Assay Technologies
- 17. To help youget started … Two Free RT2 Profiler PCR Arrays Both from the same pathway of your choice With the purchase of master mix and first strand kit reagents Sales and Technical Questions: SUPPORT@SABIOSCIENCES.COM Questions about our Webinars: QIAWEBINARS@QIAGEN.COM - 17 - Sample & Assay Technologies
- 18. What’s Your CellLine Saying? Cell Junctions & Cell Biology Q&A George J. Quellhorst, Jr., PhD Associate Director, R&D Biological Content Development . . . Sample & Assay Technologies