Cell Adhesion Flashcards by Camelita Thrift

What is the result of interaction of caherins from adjacent cells?

Electron dense line in intercellular space

How well did you know this?

Not at all

Perfectly

What are the two types of adherin junctions?

Cell-to-cell junctions

Cell-to-ECM adhesive junctions

How well did you know this?

Not at all

Perfectly

What are the roles of focal adhesion?

Provides linkage of cell to extracellular matrix

Important for intracellular signaling

How well did you know this?

Not at all

Perfectly

What are the transmembrane adhesive proteins of focal adhesion?

Integrin heterodimers

How well did you know this?

Not at all

Perfectly

What is a gap junction?

They directly connect the cytoplasm of two cells, which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells.

How well did you know this?

Not at all

Perfectly

What is the intergral membrane protein in gap junctions?

Connexin

How well did you know this?

Not at all

Perfectly

Role of desmosomes

Provides firm adhesion among cells

How well did you know this?

Not at all

Perfectly

What is focal adhesion?

The dynamic assembly of many different proteins

How well did you know this?

Not at all

Perfectly

Junctional combinations

Junctional complex: cuboidal or columnar epithelium

Intercalated disc: Cardiac muscle

How well did you know this?

Not at all

Perfectly

3 main roles of adherens junction

Contribution to adhesive force between one call and another

Support to apical domain of epithelial cells

Intracellular signaling

How well did you know this?

Not at all

Perfectly

Adhesive junctions are commonly involved in __________ for ________, ________, and ____________.

Loss of contact to adjacent cells or extracellular matrix may trigger ___________ or result in loss of ____________

Intracellular signaling; nuclear transciption; tumor suppression; differentiation

apoptosis; polarity

How well did you know this?

Not at all

Perfectly

6 connexins form __________, which is a ______________

Connexon; connexin hemichannel

How well did you know this?

Not at all

Perfectly

What are the cytoplasmic adapter proteins in adheren junction?

Alpha and beta catenin

p120 catenin, afadin, vinculin, and alpha actinin

How well did you know this?

Not at all

Perfectly

Adherin junctions

Adhesive junction with _______________ intercellular space and ____________ plaque on cytoplasmic face.

Associated with belt-like bands of _________

Encircles ____________

Found basil to ___________ in epithelial cells

Electrion-lucent

“Fuzzy”

Actin

Entire cell

Tight junction zonula

How well did you know this?

Not at all

Perfectly

Layers of basal lamina

Lamina lucida

Lamina densa

Lamina fibroreticularis

How well did you know this?

Not at all

Perfectly

What are some cytoplasmic proteins?

Kinases, transciption factots, cell polarity- related proteins

How well did you know this?

Not at all

Perfectly

Types of Junctions

Gap Junction

Tight Junction

Adherin junctions

How well did you know this?

Not at all

Perfectly

What are transmembrane adhesive proteins that are found in desmosomes?

Cadherins; desmoglein; democollin

How well did you know this?

Not at all

Perfectly

Arrangement of Intercellular Junctions. Definition of Each Arrangement

Macula: patch-like junction of limited extent

Zonula: junction who encircles the entire cell

How well did you know this?

Not at all

Perfectly

What are tight junctions?

multiprotein junctional complex whose general function is to prevent leakage of transported solutes and water and seals the paracellular pathway.

How well did you know this?

Not at all

Perfectly

Basal lamina/ basement membrane

Sheet-like arrangement of ___________proteins.

Binds __________to underlying __________

extracellular matrix

epithelium connective tissue

How well did you know this?

Not at all

Perfectly

Which junction is a plaque like junction?

Gap

How well did you know this?

Not at all

Perfectly

In gap junctions, the cell membranes of neighboring cells are very close together; intercellular space only ________nm. They can be found ___________. Common in ____________,_______ and ________, ______________, and ___________.

2-3; all basic cell types; epthelial cells, smooth and cardiac muscle cells; neuronal cells, and osteocytes.

How well did you know this?

Not at all

Perfectly

What are the cytoskeletal elements of desmosomes?

Intermediate filaments (type depends on tissue type)

How well did you know this?

Not at all

Perfectly

In which junction are cells held together or attached to the extracellular matrix?

Adherin junctions

What are the cytoskeletal elements of hemidesmosome?

Intermediate filaments

What are the cytoplasmic adapter proteins of focal adhesion?

Alpha-actinin, vinculin, talin

Heterodimers with alpha and beta subunits

Integrin

Actin filaments are associated with which type of junction?

Tight Junction

What is the intercellular space beween attached cells at adhesive junctions?

20 nm

Tight junctions are also known as \_\_\_\_\_\_\_\_\_\_\_

Occluding

Integrins bind to extracellular matrix proteins \_\_\_\_\_\_\_\_\_\_,\_\_\_\_\_\_\_\_\_\_\_, and \_\_\_\_\_\_\_\_\_\_\_.

Fibronectin, laminin, collagen

Which junction has anastomosing strands of adhesive transmembrane proteins?

Tight junctions

What is the cytoskeletal element in adherens junctions?

Actin

In gap junctions, an aqueous channel is formed between the _________ of adjacent cells, which allows for the passage of ______________ and \_\_\_\_\_\_\_\_\_\_\_\_\_. Connected cells are _____________ coupled for ______________ responses to \_\_\_\_\_\_\_\_\_\_\_\_\_. Different members of the connexin family result in difference in \_\_\_\_\_\_\_\_\_\_\_\_\_

Cytoplasm; small signaling molecules; ions; electronically; coordinated; stimuli; permeability

Gap junctions are also known as\_\_\_\_\_\_\_\_\_\_\_\_

Communicating Junctions

Integrins bind to basal lamina glycoprotein \_\_\_\_\_\_\_\_\_\_

Laminin

What is an example of a junction found in cardiac mucscle and which types of cell adhesion comprise it?

Intercalated disc Fascia adherins, demosome, and gap junctions

What disease is linked to mutations of genes for desmosomal, hemidesmosomal, and intermediate filament proteins

Epidermolysis bullosa

Connexons of one cell connect to the connexons in adjacent cell to form _____________ channel

Hydrophilic

Typical components of Intercellular Junctions

Transmembrane adhesive protein Cytoplasmic adapter protein Cytoskeletal filament

What do tight junctions control/ prevent?

The movement of ions and small molecules in intercellular space

In adherens junctions, _____________ interact with cytoplasmic domains of transmembrane proteins, cytoskeletal proteins, and other cytoplasmic proteins.

Catenins

Tight junctions have ____________ series of contacts to proteins of adjacent cell. The __________ is obliterated at contact site. The junctions encircles the \_\_\_\_\_\_\_\_\_\_\_\_\_. Tight junctions are found close to the __________ end of __________ or _________ \_\_\_\_\_\_\_\_ cells.

Linear; intercellular space; entire cell; apical; cuboidal; columnar epithelial cells

What cytoplasmic adapter proteins are found in desmosomes?

Desmoplakin, plakoglobin; plakophilin

What are the components of the basal lamina/ basement membrane?

Heparan sulfate (glycosaminoglycan) Collagen type IV Fibronectin Laminin Entactin Collagen type III Collagen type VII

What are the roles of the basal lamina or basement membrane?

Provides metabolic support Filters material (barrier function) Controls epithelial growth and differentation; prevents downward epithelial growth

Disk-shaped adhesive junction

Desmosome

What are the three components of a junctional complex?

1. A band of tight junctions, forming an occluding zone in the top position 2. A band of anchoring junctions in the middle position (zonula adherens) 3. A circle of spot desmosomes, in the bottom position

What is the transmembrane adhesive protein for adherens junction?

E-cadherin; Nectin

What are the transmembrane proteins of tight junctions?

Member of claudin family (4 pass membrane proteins) and occludin (junctional adhesive molecule)

What is pemphigus vulgaris?

Autoimmune disease affecting oral mucose due to production of antibodies to cadherins in desmosomes.

What is the intercellular space between desmosomes and what are the spaces filled with?

30nm; higly-ordered proteins

Where are desmosomes found?

Found basal to zonula adeherens in epithelial cells in band encicling cell Scattered over lateral cell surface

What are adherin junctions and what is a specific type?

protein complexes that occur at cell–cell junctions in epithelial and endothelial tissues, usually more basal than tight junctions. Desmosomes

What is the transmembrane adhesive proteins of hemidesmosomes?

Integrin

In tight junction, transmembrane adhesive proteins interact _________ with proteins in adjacent cells.

Homotypically

What are the differences between the two types of adherin junctions?

In cell-to-cell adhesive junctions, transmembrane adhesive proteins members of of cadherin family and cytoplasmic adapter proteins are members of the catenin family In cell-to- ECM adhesive junctions, transmembrane proteins are members of integrin family

Calcium ion-dependent proteins

Cadherin

In hemisdemosomes, the cytoplasmic adapter proteins are\_\_\_\_\_\_\_

Bulbous pemphigold antigen 230 (BP230); Plectin

What diseases are linked to connexin mutations?

Deafness, cataracts, Charcot-Marie-Tooth demyelinating disease, oculodentaldigital dysplasia

What is the major role of hemidesmosomes?

Provides tight anchoring of epithelial cell to basal lamina and underlying connective tissue