1 - Intro

Question 1

goals of chemical biology

Answer 1

1. chemical tools to facilitate advances in biology

2. biological tools to facilitate chemistry and biology

Question 2

examples of chemical tools to facilitate advances in biology

Answer 2

• fluorophore-labeled antibodies enable visualization of cell structures
• small molecules can be used to control cell function and processes therefore inhibitors allows you to understand/isolate processes

Question 3

examples of biological tools to facilitate chemistry and biology

Answer 3

• new/improved molecular (protein-based) tools can advance chemistry

Question 4

chemical biology tools

Answer 4

• small molecule voltage indicators
• genetically encoded voltage indicators
• halotags

Question 5

small molecule voltage indicators

Answer 5

• fluorescent molecules added to neurons that indicate when an action potential is initiated
• solvatochromic response or photoinduced electron transfer

Question 6

solvatochromic response

Answer 6

• fluorescent molecules move inside the membrane after depolarization
• becomes more fluorescent inside the membrane
• merocyanine 540

Question 7

photoinduced electron transfer

Answer 7

• fluorescent molecules are attached to the membrane
• voltage dependent
• more fluorescent in the absence of an electron donor/acceptor after depolarization
• quenching (decreasing fluorescence) occurs in the presence of an electron donor/acceptor after hyperpolarization
• voltagefluor 2.1.Cl or BeRST 1

Question 8

genetically encoded voltage indicator

Answer 8

• green fluorescent protein is a genetically encoded fluorophore
• GFP is not as bright or photostable as halotag
• VSD based or FRET to opsin based GEVI

Question 9

VSD based GEVI (ASAP)

Answer 9

• GFP attaches to a protein embedded in the membrane
• protein embedded changes shape after depolarization
• change in fluorescence of GFP after protein conformation is changed

Question 10

FRET to Opsin based GEVI (Ace2-mNeonGreen)

Answer 10

• GFP attaches to opsin (opsins bind to retinal)
• absorbance of opsin changes after depolarization
• change in absorbance results in quenching of GFP

Question 11

halotag

Answer 11

• synthetic fluorophore
• chemical biology alternative to GFP
• halo-tag fusion (genetically encoded biology part) attached to halo-tag ligand (chemical part)

Question 12

voltron

Answer 12

• similar to FRET to opsin based GEVI but GFP is replaced with a halotag
• brighter and more photostable than GFP-based