Nonenzymatic Protein Functions Flashcards
What are the 5 structural proteins?
- Keratin
- Collagen
- Tubulin
- Actin
- Elastin
What are the 2 motor proteins associated with microtubules? How does each work?
- Kinesins: play a role in aligning chromosomes during mitosis
- Dyneins: involved in sliding movement of cilia and flagella
How does the affinity of binding proteins and transport proteins differ?
binding: high affinity for target regardless of concentration
transport: affinity varies depending on concentration
What are the 3 cell adhesion proteins? Which is the weakest?
- Cadherins
- Integrins
- Selectins: weakest
How do cadherins work?
They help bind 2 cells of the same type using Ca2+
How do integrins work? What do they contain?
They help bind one cell to proteins in extracellular matrix
Contain two membrane-spanning chains: play a role in cellular signaling)
How do selectins work?
They help bind one cell to carbohydrates on the surface of other cells
Which type of ion channel maintains the resting membrane potential?
Ungated
What are voltage gated channels regulated by?
Membrane potential
How do ligand-gated channels work?
The binding of a ligand causes the channel to open or close
What are the 3 protein domains of enzyme-linked receptors and their role?
membrane-spanning: anchors receptor in membrane
ligand-binding: stimulated by a certain ligand and induces conformational change to activate the 3rd domain
catalytic domain: acts as an enzyme
What are G-protein coupled receptors characterized by?
7 membrane-spanning alpha helices (like a snake)
In what organisms are G-protein coupled receptors found?
Eukaryotes only
What is special about G proteins?
They have the ability to bind GTP and GDP
What is special about the G proteins interacting with the GCPRs?
They are hetero trimers: alpha, beta, gamma subunits
