CH3 Non-enzymatic protein function and protein analysis

Question 1

Structural Proteins:

• Collagen
• Elastin
• Keratin
• Actin
• Tubulin

Answer 1

• Collagen: makes up most of the extracellular matrix of connective tissue
• Elastin: part of connective tissue, role is to stretch and then recoil.
• Keratin: Intermediate filament protein. Makes up hair and nails
• Actin: make sup microfilaments, seen in muscle
• Tubulin: Makes up microtubules, important in chromosome separation

Question 2

Motor Proteins:

• Myosin
• Kinesin
• Dynein

Answer 2

• Myosin: Primary motor protein that interacts with actin
• Kinesin: Move things towards the positive end, towards post synaptic bud.
• Dynein

Question 3

Cell adhesion molecules: function?

• Cadherins
• Integrins
• Selectins
  *

Answer 3

• Cadherins: Cad = Calcium, mediate calcium-dependent cell adhesion
• Integrins: Important in cellular signaling. i.e to activate clotting factors
• Selectins:

Question 4

Protein Isolation Methods

• Electrophoresis
• Isoelectric Focusing
• Chromatography
• Column Chromatography
  *

Answer 4

• Electrophoresis: Separates proteins by charge, - towards the anode (+), and + towards the cathode (-) (like in electrolytic cell)
• Isoelectric Focusing: Based on AA Ip (pH where the AA is neutral) start at low pH (Protonated and near the Anode (+) ) move towards higher pH and the Cathode (-)
• Chromatography: based on polarity and affinities to mobile or stationary phase
• Column Chromatography

*

Question 5

• Native PAGE:
• SDS PAGE:

Answer 5

• Native PAGE: Polyacrylamide gel electrophoresis (PAGE) Proteins with low mass and high charge will move farther like in electrophoresis
• SDS PAGE: Sodium dodecyl sulfate. Same as PAGE but with SDS which disrupts all interactions except covalent
  *