The plant cell contains a unique organelle known as the chloroplast which is reponsible for conducting oxygenic photosynthesis. Both oxygen and carbohydrates are the main products of light-induced photosynthesis that is dependent on both water and sunlight. However, the real outcome of photosynthesis in plants is to provide the plant cell with the energy source ATP and the reducing power of NAPDH both of which are used in a plant cell's dark-induced reactions of photosynthesis. Inside the chloroplast's stroma one can find the photosynthetic membrane also known as the thylakoid membrane which houses the photosynthetic apparatus.

Arabidopsis thaliana (A.thaliana) a small weed of the Brassicacea family was employed for this project as a plant model to understand the functions of a specific protein known as Tandem Pore Potassium Channel (AtTPK5).

As the name implies AtTPK5 is a transport system of potassium ions but the location and role of this protein in the plant cell has not been fully explained.

The aim of the present project were the following:

(i) to screen for homozygous (HM) mutants which would have fully lost or partially lost their ability to express AtTPK5.

(ii) to elucidate the physiological role of AtTPK5 in A.thaliana by comparing plant fitness and photosynthesis in both mutant and wild-type plants. 

The experimental hypothesis for this project was that a knock-out or knock-down of AtTPK5 protein expression will negatively affect photosynthetic activity.