Anabaena Sensory Rhodopsin (ASR) is a retinal containing membrane protein from Anabaena nostoc. ASR undergoes an orange-light induced conformational change from an all trans form to a 13-cis form, which is associated with the release of a bound transducer protein ASRT. It is proposed that the ASR/ASRT complex directly controls the transcription of phycocyanin (cpc-gene) and phycoerythrocyanin (pec-gene). In order to study this protein complex, ASR nanolipoprotein particles (nanodiscs) were assembled, which allows both ends of the ASR protein to be studied. These particles will enable the main goal of this research, which is to identify the mechanism of the ASR/ASRT control of transcription.