glycocaylx
external layer of the lipid bilayer, glycoproteins and glycolipds may have carbohydrates covalently attached.
Function: cell-to-cell and cell-to-extracellular matric recognition.
microtubules (MTs)
- made out of dimers (alpha, beta)
- dynamically instable
- growth happens more at the (+) end (polarized)
- Make up mitotic spindle
- serve as cell railways
- determinant of cell shape
- core of Cilia and flagella
- component of basal bodies and centrioles
kinesin
motor protein. moves on MTs from (-) to (+) end
dynein
motor protein. moves on MTs from (+) to (-) end
centrisome
microtuble organizing center (MTOC). (-) ends are anchored to MTOC
basal bodies
made up of 9 microtubule triplets. body of cilia and flagella
Motile Cilia and Flagella
Core of 9 doublets plus 2 core singlets (MTs)
- Dynein arms
- Nexin connectors
- radial spokes to center
Axoneme
Structural core of cilia and flagella
primary cilia
core of 9 doublets with no center core (MTs)
- establish left-right asymmetry
- single cilia
Intermediate Filaments
- rod like coiled dimers
- used as a marker to determine the tissue source of the origin of tumor cells.
- anchored to desmosomes
Microfilaments
aka Actin
- dynamic and polarized
- motor protein myosins
- part of cell cortex (gives shape to cell)
- forms the core and body of microvilli
- aids in zonula and fascia adherens juntions
- provide cell movement
- separates daughter cells.
tight junctions
zonula occludens
- belt like structure around cell
- most apical
- transmembrane proteins seal the juntion
adhering junction
desmosomes
zonula adherens
hemidesmosome
- uses actin or IFs to connect to cytoskeleton
- Adaptor proteins- anchor CAMs to cytoplasmic domain
- Cell adhesion molecules (CAMs)- bind cell to lamina or cell to cell
Zonula adherens
adhering junction
- Continuous belt-like
- CAMs- E-cadherin
- adaptor proteins- vinculin, catenin, and alpha-actinin
Macula Adherens
Desmosome
- Adaptor proteins- desmoplakin and plakoglobins
- third highest on apical side of epithelia
Hemidesmosome
- anchor IFs to cells
- anchors cell to basal lamina
- CAMs- integrin and Type XVII collagen
- adaptor proteins- plectin, erbin and bpag1
Gap Junctions
aka Nexus
small acqueous channels that allow ions and small molecules to pass between cells
connexin units form a single connexon unit
