Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, 630-0192 Japan.
Plant Cell Physiol. 2010 Apr;51(4):664-8. doi: 10.1093/pcp/pcq030. Epub 2010 Mar 8.
Cyclic electron transport around PSI has been proposed to supply the additional ATP required for C(4) photosynthesis. To investigate the nature of cyclic electron pathways involved in C(4) photosynthesis, we analyzed tissue-specific expression of PGR5 (PROTON GRADIENT REGULATION 5), which is involved in the antimycin A-sensitive pathway, and NDH-H, a subunit of the plastidial NAD(P)H dehydrogenase complex, in four Flaveria species comprising NADP-malic enzyme (ME)-type C(4), C(3)-C(4) intermediate and C(3) species. PGR5 was highly expressed in the C(4) species and enriched in bundle sheath chloroplasts together with NDH-H, suggesting that electron transport of both PGR5-dependent and NDH-dependent cyclic pathways is promoted to drive C(4) photosynthesis.
已经有人提出,围绕 PSI 的循环电子传递可以为 C(4)光合作用提供额外的 ATP。为了研究与 C(4)光合作用相关的循环电子途径的性质,我们分析了 PGR5(质子梯度调节因子 5)和 NDH-H 的组织特异性表达,这两者都参与了抗霉素 A 敏感途径,以及四个 Flaveria 物种中的质体 NAD(P)H 脱氢酶复合物的一个亚基,这四个 Flaveria 物种包括 NADP-苹果酸酶 (ME)-型 C(4)、C(3)-C(4)中间型和 C(3)型。PGR5 在 C(4)物种中高度表达,并与 NDH-H 一起富集在束鞘叶绿体中,这表明 PGR5 依赖和 NDH 依赖的循环途径的电子传递都得到了促进,以推动 C(4)光合作用。