Poster: Transcription Regulation

Abs # 1069: The gene expression of thecfxQ of Cyanidioschyzon merolae in the plastid genome and in the cell nucleus

Presenter:	Fujita, Kiyotaka , niji@molbiol.saitama-u.ac.jp
Authors	Fujita, Kiyotaka  (A)   Ohta, Niji  (A)   Sadaie, Yoshito  (A)
Affiliations:	(A): Department of Molecular Biology, Faculty of Science, Saitama University

Cyanidioschyzon merolae is classified in protoflorideophycceous algae of rhodophytes, and thought to be a most primitive alga. It contains one cell nucleus, one mitochondrion and one plastid in its interphase. It can culture by synchronously, and therefore it is a good material for investigate the gene expression with time course. C. merolae contain the cfxQ gene both in the plastid and in the cell nucleus (see Ohta et al.). The role of cfxQ is not clear. It is co-transcribed with rbcL and rbcS (L and S subunit of RuBisCO). We examined the gene expression of the two cfxQs with synchronous culture with 12 hours light and 12 hours dark. In the light period, the genes are very actively transcribed. In the dark period, the gene expresses in low level. The light period comes to near, the genes begin to be transcribed. The timing of the beginning of the cfxQ in the cell nucleus is different from that in the plastid genome. The cfxQ in the cell nucleus expresses earlier than that in the plastid genome in the dark period. The results suggests that (1) The two cfxQ gene are controlled different system and (2) the cfxQ in the cell nucleus may cause the RuBisCO operon in the plastid genome.