Transmembrane kinases
require multiple membrane passes, activated by proximity to other TKs and structural rearrangements
when activated, they recruit proteins and phosphorylates them to perform a specific function
Ligands
small molecules that bind to the proteins or glycoproteins
adrenaline binds to Wnt and attaches to protease-activated receptors
Activated receptors
animals: GEFs (active Ga), recruits and activates effectors
plants: GAPs (inactive Ga)
Ligand-activated transcription factors
steroid receptors, retinoid receptors, prostaglandins
Plant cell wall composition
Paths molecules can take to move through the plant
apoplectic path through the cell wall space
symplastic path through the plasmodesmata
Direction of cell growth is determined by the
deposition of cellulose fibers in the cell wall, that are extruded from the cell membrane into the extracellular space guided by the microtubules
Collagen
secreted as procollagen, provides tensile strength