Preliminary characterization of the Chlamydomonas thylakoid-associated kinase Stl1

Christian Delessert and Jean-David Rochaix

Plant and Molecular Biology departments, Geneva University

Photosynthetic organisms have the capacity to adapt to differences in light quantity and quality through a variety of means. Short term adaptation is characterized by phosphorylation of the mobile part of the LHCII antenna and their migration from PSII-rich grana to PSI-rich lamellae. This process called state-transition occurs both in land plants (Arabidopsis) and algae (Chlamydomonas) and involves a LHCII specific thylakoid-associated kinase named STN7 or Stt7 respectively. In Arabidopsis, a paralog of the STN7 kinase (STN8) is involved in the phosphorylation of PSII core proteins (D1/D2, CP43 and PsbH) and appears to act synergistically with STN7. Moreover, STN8 orthologue protein in Chlamydomonas (Stl1) is phosphorylated in a Stt7-dependent manner. Although much effort has been invested in understanding the role of Stt7 and STN7 in the past years, little is known about STN8 or Stl1. Here, we will present preliminary results aiming at the characterization of Stl1 in Chlamydomonas.

e-mail address of presenting author: christian.delessert@gmail.com