[11:12 am, 22/08/2020] Lakshmy CUBE Kerala:
Summary of CUBE chatasaala 21/8/2020 discussion by Lakshmy from Thrissur, Kerala
Yesterday we have great discussion about circadian rhythm comparative study on drosophila and phyllanthus.
Aswathy draw an approximate graf about sleep wake cycle of phyllanthus and drosophila of 3 days with respect to sunrise (6am) and sunset time (6pm)
Aswathy expected that the number of fruit flies started to increase at sunrise time and and started decreasing at sunset time. But according to her original data, even after sunset there is maximum number of fruit flies (8pm) . Then after the number of fruit flies decreased.
Saida explained about the molecular aspects of circadian rhythm in fruit flies, ie, the mechanism of PER &TIM genes in drosophila. She said that the production of PER &TIM protein is maximum during sunset time .And later these proteins bind together and move from cytoplasm to nucleus and take away the CIK& CYC transcription factors and prevent the expression of PER &TIM genes. That induce sleep in drosophila. Saida initially expected that the number of fruit flies decreased from the sunset time onwards. But aswathy result is slightly different.
But Arunan Sir explained it with a simple
Example that even after switch of the AC there will be still cooling in the room for some time. Like that even though the production of PER proteins is maximum at sunset time even after that the proteins will be produced.
Later Lakshmy also explained about the circadian rhythm molecular mechanism in Arabidopsis thaliana. There is three genes responsible for circadian rhythm.
1.CCA1(CIRCADIAN CLOCK ASSOCIATED 1)
2. LHY (LATE ELONGATED HYPOCOTYL)
3. TOC1 (TIMING OF CAB EXPRESSION 1)
CCA1 &LHY function is same as PER& TIM gene in drosophila.
CCA1 &LHY gene production is maximum during sunrise time. Later these proteins bind together and later bind to the TOC1 promoter region and prevent the expression during day time. During evening time the expression of TOC1 is maximum that induced sleep .
Understanding sleep wake cycle of both phyllanthus and drosophila was really informative.