光照是進行光合作用的要素之一，由光誘導之啟動子( light-responsive promoter )，大部分
與葉綠體基因功能之表現有關，受光調節之啟動子上游區域常具有一些重要的光調控motif
位置，例如GATA、G-box (CACGTC/G)、I-box (GATAA) 和GT-1 box (GGTTAA) 等，這些
都是在光調節反應中與順勢作用元件(cis-acting elements) 結合的重要位置。SBPase
(sedoheptulose-1,7-bisphosphatase)的重要特性為（一）在卡爾文循環(Calvin cycle)中碳釋出
(carbon flux)之主要調節酵素。（二）SBPase 的催化活性主要是由光來調控其cysteines 之還
原氧化(thioredoxin)狀態，且其需在還原狀態下才有活性。
小麥和阿拉伯芥兩者之SBPase 基因序列有79% 之相同性(identities);而高等植物與單胞
藻(Chlamydomonas reinhardtii) 有73% 之相同性，小球藻(Chlorella pyrenoidosa)與單胞藻(C.
reinhardtii) 有80% 之相同性，若能研究開發增強小球藻(Chlorella pyrenoidosa) SBPase 之光
誘導啟動子效率，除了能提高其固碳率與產量外，亦可釐清其光誘導啟動子之作用機制。 Light is essential for photosynthesis in plant. In general, the regulation of light-responsive
promoter (LRP) is related to plastid genes expression. However, the extent to which illumination
controls plastid gene expression varies depending on plant species and the developmental stages of
the tissue. The LRP is able to enhance the transcription rate of genes. Some Photo-regulated motif
are localized in the upstream of light-regulated promoter. Such as the GATA motif, G-box
(CACGTC/G), I-box (GATAA) and GT-1 box (GGTTAA) sites which interact with the cis-acting
elements. It has shown that SBPase is a key regulator of carbon flux in Calvin cycle and the redox
active cysteines are responsible for the regulation of SBPase catalytic activity by light.
A comparison of the wheat and Arabidopsis SBPase gene sequences revealed that they are 79%
identity. Then, the algal has around 73% and 80% identity with SBPase from higher plants and C.
reinhardtii, respectively. Study on the mechanism of LRP to increase the rate of carbon fixation and
production in Chlorella pyrenoidosa.
