State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, 361012, China; College of Biological Science and Engineering, Fuzhou University, Fuzhou, 350108, China.
State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, 361012, China.
Harmful Algae. 2018 May;75:27-34. doi: 10.1016/j.hal.2018.04.002. Epub 2018 Apr 16.
PCP and acpPC are the two major antennae proteins that bind pigments in peridinin-containing dinoflagellates. The relationship between antennae proteins and cellular pigments at molecular level is still poorly understood. Here we identified and characterized the two antennae protein genes in dinoflagellate Prorocentrum donghaiense under different light conditions. The mature PCP protein was 32 kDa, while acpPC was a polyprotein each of 19 kDa. Both genes showed higher expression under low light than under high light, suggesting their possible role in a low light adaptation mechanism. The two genes showed differential diel expression rhythm, with PCP being more highly expressed in the dark than in the light period and acpPC the other way around. HPLC analysis of cellular pigments indicated a diel change of chlorophyll c2, but invariability of other pigments. A stable peridinin: chlorophyll a pigment ratio was detected under different light intensities and over the diel cycle, although the diadinoxanthin:chlorophyll a ratio increased significantly with light intensity. The results suggest that 1) PCP and acpPC genes are functionally distinct, 2) PCP and acpPC can function under low light as an adaptive mechanism in P. donghaiense, 3). the ratios of diadinoxanthin:chlorophyll a and peridinin: chlorophyll a can potentially be used as an indicator of algal photophysiological status and a pigment signature respectively under different light conditions in P. donghaiense.
PCP 和 acpPC 是结合含 Peridinin 甲藻细胞色素的两种主要天线蛋白。在分子水平上，天线蛋白与细胞色素之间的关系仍知之甚少。在这里，我们鉴定并描述了东海原甲藻在不同光照条件下的两种天线蛋白基因。成熟的 PCP 蛋白为 32kDa，而 acpPC 是一个 19kDa 的多蛋白。这两个基因在低光下的表达高于高光下，表明它们可能在适应低光机制中发挥作用。这两个基因表现出不同的昼夜表达节律，PCP 在黑暗中的表达高于光照期，而 acpPC 则相反。细胞色素的 HPLC 分析表明叶绿素 c2 的昼夜变化，但其他色素不变。尽管二氢叶黄素：叶绿素 a 的比值随光照强度显著增加，但在不同光照强度和昼夜周期下均检测到稳定的 Peridinin：叶绿素 a 色素比值。结果表明：1）PCP 和 acpPC 基因在功能上是不同的；2）PCP 和 acpPC 可以在低光下作为东海原甲藻的适应机制发挥作用；3）在不同光照条件下，二氢叶黄素：叶绿素 a 和 Peridinin：叶绿素 a 的比值可以分别作为藻类光生理状态和色素特征的指标。
