Proof of concept

Expression level of protein HHL1

After tranfection, we incubate the protoplasts at 2 groups of light intensities to induce the expression of hhl1.

We use semi-quantitive RT-PCR to detect the mRNA from gene hhl1 in protoplasts,the concentration of amplified cDNA of each group is measured by fluorescent quantitation. Data of the concentration of amplified products are used to calculate the relative expression level of mRNA.

Growth light High light
Phhl1 1 0.05 1.1 0.07
Pcop1 1 0.03 10.1 1.26
Ppif1 1 0.06 8.9 1.01
PphyB 1 0.09 15.6 1.36

This graph shows the relative expression level of mRNA of gene hhl1 expressed by 4 different parts under growth light(100lux) and high light(1200lux).

pCop1,pPif1,pPhyB do not respond to growth light, the expression level of mRNA is similar to that of pHhl1.However, under high light,three photosensitive promoters all respond specifically and the expression level of mRNA is obviously higher than that in pHhl1.(The transcription level of pCop1,pPif1 and pPhyB under highlight are 10.1,8.9 and 15.6 times of the mRNA level under growth light,respectively.),suggesting that our parts can help produce more protein HHL1 to protect PSⅡ under high light.

(the relative expression level of mRNA of pHhl1 under high light doesn’t change much,but after translation the expression level of protein HHL1 is increased compare to pHhl1 under growth light).