Zebrafish

Question 1

Proof of multiple zebrafish clocks

Answer 1

Cultured pineal glands showed rhythmic release of melatonin
Rhythmic expression of clock in the eye
Clock mRNA oscillated throughout the brain of an adult fish
Cultured heart tissue had its own clock

Question 2

Who showed that zf pineal glands had a clock

Answer 2

Cahill et al 1996

Question 3

How was rhythimic expression of clock genes seen thorught the zebrafish body and who by

Answer 3

Dissected various parts of the body, kept in tissue culture and left in the dark for 2 days (heart) and 3 days (kidney) Done by Whitemore et al. constant dissection and monitoring of levels needed

Question 4

How are the clocks entrained in zebrafish

Answer 4

Using light, however not from the eyes. Masterblind fish show the same entrainment as WT

Question 5

New method for monitoring oscillations that doesnt involve dissection

Answer 5

Using luciferase to attached to a promoter before the gene of interest, can then monitor the light patterns

Question 6

How much can a 1 hour light pulse shift the clock by?

Answer 6

12 hrs

Question 7

Do cells maintained in darkness show oscillations

Answer 7

Yes, but no synchronously. A 15 minute light pulse can get them to synchronise.