Glossary of Cell Surface Specialization

Start Studying! Add Cards ↓

apical domain
region of PM that borders luminal space
Basolateral domain
region of PM in contact with extracellular matrix
nonmotile rigid bundle of microfilaments bound by villin with + end at the tip
terminal web
dense network of actin filaments, spectrin and cytokeratin (IF)
striated border microvilli
shortest microvilli uniform in length and found on intestinal epithelium
brush border
microvilli that are longer and less uniform and found in proximal tubules of nephrons
long, nonmotile microvilli found in epididymal epithelium and hair cells in the inner ear
intercellular secretory canaliculi
increase surface area between cells for exocytosis in glands and terminate blindly above basal lamina
basal infoldings
invaginations of basal PM to increase basal contact SA with ECM; form labrynth that creates basal striations with mitochondria between
What confine transport proteins to their appropriate domains by acting as a diffusion barrier?
tight junctions (zonula occludens)
zonula occludens (tight junction)
junction between cells composed of strands of long rows of specific transmembrane proteins in each cells PMs which join directly to occlude intercellular space
protein in tight junctions that form linear fibrils to creat diffusion barriers for solutes, ions and water
transmembrane protein that interacts with 4 major intracellular peripheral proteins
fascia occludens
junction found between capillary endothelial cells
zonula adherens
encircles each cell near apex just below tight junction. Calcium dependent
transmembrane linker protein that mediates zonula adherens between epithelial cells
anchoring sites for IF to form a continuous structure throughout the tissue
basal lamina
specialized mat of ECM @ the interface between epithelium and connective tissue
integrin found in hemidesmosomes and is the only integrin to connect intermediate filament
Junctional complex
tight junction + zonula adherens + desmosome
transmembrane proteins that align to form a hydrophilic channel between two cells in gap junctions
paracrine communication
uses local chemical mediators which are rapidly taken up and destroyed or immobilized and can only act on immediate environment
endocrine communication
specialized cells secrete hormones (steroids and water soluble hormones) that travel through vasculature to influence cells over greater distances.
synaptic signalling
cells secrete neurotransmitters at specialized junctions (synapses)
Cells organized into tissues and organs have more or less highly ordered domains in the PM than single cells?
functions of apical domain
regulates nutrients and water, protection and regulated secretion
Which domain contains hydrolases and Na+
apical domain
Functions of basolateral domain
signal reception and transduction, generation of ion gradients and constituitive secretion
Where is villin found
What provides rigidity and stability to the cortex near PM
functions of microplicae
found on the free surface of cells to 1) increase the surface area 2) hold and spread mucus and other secretions 3) maintain moisture on free surface of cells 4) and transport antigens (M cells)
What are the 3 functional groups of cell junctions
occluding, anchoring, and communicating
what are the 3 structural groups of cell junctions?
zonula, fascia, macula
what are the four intracellular peripheral proteins that interact with occludin in tight junctions?
ZO-1, ZO-2, ZO-3, AF-6; these anchor strands to Actin
how does the cytoplasmic domain of E-cadherin interact with actin
three intracellular attachment proteins called α, β, γ catenins
what junction is part of the intercalated disc in cardiac muscle
fascia adherins
what is another name for macula adherens
in what cells are desmosomes made of keratin or tonofilaments found?
in what cells are desmosomes made of desmin filaments found?
cardiac muscle cells
Where is a dense plaque of desmoplakins and plakoglobins found?
on the INTRACELLULAR side of the membrane of desmosomes
What transmembrane linker proteins do hemidesmosomes use?
integrin (α6β4 )
gap junctions are characterized by what?
close apposition of adjacent plasma membranes
how can cells be chemically and electrically coupled and coordinate activities and responses?
gap junctions
What are the 4 types of indirect communication?
autocrine, paracrine, endocrine, and synaptic signalling

Add Cards

You must Login or Register to add cards