Hemidesmosome

hemidesmosomeshemidesmosomaladhesion complexes
Hemidesmosomes are very small stud-like structures found in keratinocytes of the epidermis of skin that attach to the extracellular matrix.wikipedia
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Keratinocyte

keratinocytesskin cellsdead skin cells
Hemidesmosomes are very small stud-like structures found in keratinocytes of the epidermis of skin that attach to the extracellular matrix. Hemidesmosomes are also involved in signaling pathways, such as keratinocyte migration or carcinoma cell intrusion.
Epidermal stem cells reside in the lower part of the epidermis (stratum basale) and are attached to the basement membrane through hemidesmosomes.

Epidermis

epidermalepidermal cellsepidermal layer
Hemidesmosomes are very small stud-like structures found in keratinocytes of the epidermis of skin that attach to the extracellular matrix.

Extracellular matrix

ECMmatrixextracellular matrices
Hemidesmosomes are very small stud-like structures found in keratinocytes of the epidermis of skin that attach to the extracellular matrix.
Although the mechanism by which this is done has not been thoroughly explained, adhesion complexes and the actin-myosin cytoskeleton, whose contractile forces are transmitted through transcellular structures are thought to play key roles in the yet to be discovered molecular pathways.

Lamina lucida

Hemidesmosomes are found in epithelial cells connecting the basal epithelial cells to the lamina lucida, which is part of the basal lamina.
The electron-lucent zone is adjacent to the cells of the junctional epithelium and might be considered a continuation of the lamina lucida as both are seen to harbour hemidesmosomes.

Collagen, type XVII, alpha 1

COL17A1BPAG2XVII
Type 1 hemidesmosomes have five main elements: integrin α6β4, plectin in its isoform 1a, i. e. P1a, tetraspanin protein CD151, BPAG1e, or bullous pemphigoid antigen isoform e, and BPAG2 (also known as BP180 or type 17 collagen).
Each 180 kD a-chain contains a globular intracellular domain of approximately 70 kDa, which interacts with beta4-integrin, plectin, and BP230 and is necessary for the stable attachment of hemidesmosomes to keratin intermediate filaments.

Desmosome

desmosomesdesmosomaldesmosomal cadherins
They are similar in form to desmosomes when visualized by electron microscopy, however, desmosomes attach to adjacent cells.

Plectin

PLEC1PLEC
Type 1 hemidesmosomes have five main elements: integrin α6β4, plectin in its isoform 1a, i. e. P1a, tetraspanin protein CD151, BPAG1e, or bullous pemphigoid antigen isoform e, and BPAG2 (also known as BP180 or type 17 collagen).
Plectin also functions to link cytoskeleton to intercellular junctions, such as desmosomes and hemidesmosomes, which link intermediate filament networks between cells.

Junctional epidermolysis bullosa (medicine)

junctional epidermolysis bullosaepidermolysis bullosa, junctionalCicatricial junctional epidermolysis bullosa
There are three types of EB: EB simplex (EBS), dystrophic EB (DEB) and junctional EB (JEB).
α6β4 integrin is a transmembrane protein found in hemidesmosomes.

Keratin 5

KRT5K55
BPAG1e is an antigen with multiple isoforms that binds to integrin α6β4, BPAG2 and keratin 5 and 14.
At the hemidesmosome, plectin and BPAG1 associate with transmembrane proteins α6β4 integrin, a type of cell adhesion molecule, and BP180/collagen XVII, linking K5/K14 filaments in the basal cells to the basal lamina.

Intermediate filament

intermediate filamentsdesmosome-keratinfilament
When integrin α6β4 binds to Plectin 1a and BPAG1, it associates with the keratin intermediate filaments in the cytoskeleton.
At the plasma membrane, some keratins interact with desmosomes (cell-cell adhesion) and hemidesmosomes (cell-matrix adhesion) via adapter proteins.

Electron microscope

electron microscopyelectron microscopeselectron
They are similar in form to desmosomes when visualized by electron microscopy, however, desmosomes attach to adjacent cells.

Desmoglein

desmogleinsdesmoglein I
Instead of desmogleins and desmocollins in the extracellular space, hemidesmosomes utilize integrins.

Desmocollin

desmocollinsDesmocollin 1
Instead of desmogleins and desmocollins in the extracellular space, hemidesmosomes utilize integrins.

Integrin

integrinsintegrin receptorintegrin alpha1
Type 1 hemidesmosomes have five main elements: integrin α6β4, plectin in its isoform 1a, i. e. P1a, tetraspanin protein CD151, BPAG1e, or bullous pemphigoid antigen isoform e, and BPAG2 (also known as BP180 or type 17 collagen). Instead of desmogleins and desmocollins in the extracellular space, hemidesmosomes utilize integrins.

Basal lamina

basement membranebasalbasal layer
Hemidesmosomes are found in epithelial cells connecting the basal epithelial cells to the lamina lucida, which is part of the basal lamina.

Carcinoma

carcinomascancercancerous
Hemidesmosomes are also involved in signaling pathways, such as keratinocyte migration or carcinoma cell intrusion.

Stratified squamous epithelium

stratified squamousstratified epitheliumstratified squamous epithelia
Type 1 hemidesmosomes are found in stratified and pseudo-stratified epithelium.

Pseudostratified columnar epithelium

pseudostratified epitheliumpseudostratifiedPseudostratified columnar
Type 1 hemidesmosomes are found in stratified and pseudo-stratified epithelium.

Tetraspanin

tetraspanin webtransmembrane 4transmembrane 4 superfamily
Type 1 hemidesmosomes have five main elements: integrin α6β4, plectin in its isoform 1a, i. e. P1a, tetraspanin protein CD151, BPAG1e, or bullous pemphigoid antigen isoform e, and BPAG2 (also known as BP180 or type 17 collagen). CD151, a protein of the tetraspanin superfamily, resides on the cell surface of keratinocytes and vascular endothelium.

Laminin

lamininsLaminin 5laminin-1
Integrin α6β4 operates as a laminin-332 receptor.

Fibronectin

FN1fibronectins
The larger β4 subunit has domains that bind to fibronectin III and calcium.

Keratin

keratinizationkeratinouskeratinized
When integrin α6β4 binds to Plectin 1a and BPAG1, it associates with the keratin intermediate filaments in the cytoskeleton.

Plakin

Hemidesmosomes are linked to keratin by plectin isoform 1a from the plakin protein family.

Endothelium

endothelialendothelial cellsendothelial cell
CD151, a protein of the tetraspanin superfamily, resides on the cell surface of keratinocytes and vascular endothelium.

Antigen

antigensantigenicantigenic proteins
BPAG1e is an antigen with multiple isoforms that binds to integrin α6β4, BPAG2 and keratin 5 and 14.