Structure and Function of Sphingoglycolipids in Transmembrane Signalling and Cell-Cell Interactions

Cell adhesion and cell adhesion molecules (CAMs) play a crucial role in testicular development and function. The seminiferous epithelium, the functional unit of the testis, represents a three dimensional architecture of supporting Sertoli cells (SC), and developing germ cells (GC). The seminiferous epithelium, therefore, must be receptive not only to individual cell growth and differentiation, but also to cell-cell interactions. Morphologically distinct cell-cell interactions occur between SC and GC and also between SC.[1] In general, these junctions can be categorized into three types: adhesive, occluding, and gap junctions. The orientation and function of these junctions are interaction dependent. For example, desmosome-like junctions (spot desmosomes) are found between SC and GC. These junctions are present in the basal and intermediate compartments of the testis and serve to translocate developing GC. SC-SC interactions, like the zonula occludens (tight junction), function as vectorial mediators, maintaining the blood-testis barrier and SC polarity.

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Seeing and believing: recent advances in imaging cell-cell interactions

F1000Research ◽

10.12688/f1000research.6435.1 ◽

2015 ◽

Vol 4 ◽

pp. 273 ◽

Cited By ~ 2

Author(s):

Alpha S. Yap ◽

Magdalene Michael ◽

Robert G. Parton

Keyword(s):

Electron Microscopy ◽

Developmental Biology ◽

Time Scales ◽

Super Resolution ◽

Structure And Function ◽

Cell Junctions ◽

Mechanical Forces ◽

Cell Contacts ◽

And Function ◽

Cell Cell

Advances in cell and developmental biology have often been closely linked to advances in our ability to visualize structure and function at many length and time scales. In this review, we discuss how new imaging technologies and new reagents have provided novel insights into the biology of cadherin-based cell-cell junctions. We focus on three developments: the application of super-resolution optical technologies to characterize the nanoscale organization of cadherins at cell-cell contacts, new approaches to interrogate the mechanical forces that act upon junctions, and advances in electron microscopy which have the potential to transform our understanding of cell-cell junctions.

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Selectin glycoprotein ligands.

Acta Biochimica Polonica ◽

10.18388/abp.2000_4019 ◽

2000 ◽

Vol 47 (2) ◽

pp. 393-412 ◽

Cited By ~ 19

Author(s):

I Zak ◽

E Lewandowska ◽

W Gnyp

Keyword(s):

Biosynthetic Pathway ◽

Structure And Function ◽

Cell Interactions ◽

Sialyl Lewis X ◽

Lewis X ◽

Sialyl Lewis ◽

Selectin Ligands ◽

The Common ◽

And Function ◽

Lymphatic Organs

Lectin selectins and their counter-receptors participate in discontinuous cell-cell interactions concurrent with leukocyte tethering and rolling on endothelium, which, in consequence, leads to leukocyte penetration to lymphatic organs and generation of inflammation sites. Counter-receptors are glycoproteins in which carbohydrate units, the direct selectin ligands, are built into the polypeptide framework. In this review, the distribution, structure and function of the main ligands and counter-receptors for P-, L- and E-selectins known so far, have been discussed. The common biosynthetic pathway of sialyl-Lewis x and sulpho-sialyl-Lewis x determinants of selectin ligands has been described.

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Redox-Sensitive Structure and Function of the First Extracellular Loop of the Cell–Cell Contact Protein Claudin-1: Lessons from Molecular Structure to Animals

Antioxidants and Redox Signaling ◽

10.1089/ars.2013.5706 ◽

2015 ◽

Vol 22 (1) ◽

pp. 1-14 ◽

Cited By ~ 21

Author(s):

Sebastian Dabrowski ◽

Christian Staat ◽

Denise Zwanziger ◽

Reine-Solange Sauer ◽

Christian Bellmann ◽

...

Keyword(s):

Molecular Structure ◽

Structure And Function ◽

Cell Contact ◽

Extracellular Loop ◽

Sensitive Structure ◽

And Function ◽

Cell Cell

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Organoids Models for the Study of Cell-Cell Interactions

Cell Interaction - Molecular and Immunological Basis for Disease Management ◽

10.5772/intechopen.94562 ◽

2021 ◽

Author(s):

Margarita Jimenez-Palomares ◽

Alba Cristobal ◽

Mª Carmen Duran Ruiz

Keyword(s):

Regenerative Medicine ◽

Research Field ◽

Cell Interactions ◽

Model Systems ◽

Lineage Differentiation ◽

Immune System Cell ◽

Potential Applications ◽

System Cell ◽

And Function ◽

Cell Cell

Organoids have arisen as promising model systems in biomedical research and regenerative medicine due to their potential to reproduce the original tissue architecture and function. In the research field of cell–cell interactions, organoids mimic interactions taking place during organogenesis, including the processes that conduct to multi-lineage differentiation and morphogenetic processes, during immunology response and disease development and expansion. This chapter will address the basis of organoids origin, their importance on immune system cell–cell interactions and the benefits of using them in biomedicine, specifically their potential applications in regenerative medicine and personalized therapy. Organoids might represent a personalized tool for patients to receive earlier diagnoses, risk assessments, and more efficient treatments.

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Chimeric Claudins: A New Tool to Study Tight Junction Structure and Function

International Journal of Molecular Sciences ◽

10.3390/ijms22094947 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4947

Author(s):

Abigail Taylor ◽

Mark Warner ◽

Christopher Mendoza ◽

Calvin Memmott ◽

Tom LeCheminant ◽

...

Keyword(s):

Cell Adhesion ◽

Membrane Proteins ◽

Tight Junction ◽

Quaternary Structure ◽

Structure And Function ◽

Biophysical Characterization ◽

Synthetic Strategy ◽

Α Helix ◽

And Function ◽

Cell Cell

The tight junction (TJ) is a structure composed of multiple proteins, both cytosolic and membranal, responsible for cell–cell adhesion in polarized endothelium and epithelium. The TJ is intimately connected to the cytoskeleton and plays a role in development and homeostasis. Among the TJ’s membrane proteins, claudins (CLDNs) are key to establishing blood–tissue barriers that protect organismal physiology. Recently, several crystal structures have been reported for detergent extracted recombinant CLDNs. These structural advances lack direct evidence to support quaternary structure of CLDNs. In this article, we have employed protein-engineering principles to create detergent-independent chimeric CLDNs, a combination of a 4-helix bundle soluble monomeric protein (PDB ID: 2jua) and the apical—50% of human CLDN1, the extracellular domain that is responsible for cell–cell adhesion. Maltose-binding protein-fused chimeric CLDNs (MBP-CCs) used in this study are soluble proteins that retain structural and functional aspects of native CLDNs. Here, we report the biophysical characterization of the structure and function of MBP-CCs. MBP-fused epithelial cadherin (MBP-eCAD) is used as a control and point of comparison of a well-characterized cell-adhesion molecule. Our synthetic strategy may benefit other families of 4-α-helix membrane proteins, including tetraspanins, connexins, pannexins, innexins, and more.

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Structure and function of neural networks in the retina

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102213 ◽

1988 ◽

Vol 46 ◽

pp. 26-27

Author(s):

Peter Sterling

Keyword(s):

Ganglion Cells ◽

Three Dimensional ◽

Structure And Function ◽

Synaptic Connections ◽

Visual Axis ◽

One Dimensional ◽

Cat Retina ◽

Ultrathin Sections ◽

And Function ◽

Insight Into

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

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