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是两个主要触角蛋白，它们结合含peridinin的鞭毛藻酸酯中的色素。在分子水平上触角蛋白和细胞色素之间的关系仍然知之甚少。在这里，我们确定并表征了东鞭毛甲鞭毛虫中的两个触角蛋白基因。在不同的光照条件下。成熟的PCP蛋白为32 kDa，而acpPC为19 kDa的多聚蛋白。两种基因在弱光下均比在强光下表达更高，表明它们在弱光适应机制中的可能作用。这两个基因表现出不同的diel表达节奏，其中PCP在黑暗中的表达高于在亮期，而acpPC则相反。HPLC对细胞色素的分析表明，叶绿素c2呈diel变化，但其他色素不变。尽管在二恶黄质：叶绿素a中，在不同的光强度和diel循环中检测到稳定的peridinin：叶绿素a色素比率。比率随光强度显着增加。结果表明：1）PCP和acpPC基因在功能上是不同的； 2）PCP和acpPC可以在弱光下作为东海假单胞菌的适应机制发挥作用，3）。diadinoxanthin的比率：叶绿素一个和多甲藻素：叶绿素一个可潜在地用作藻photophysiological状态的指示器和在不同光照条件下分别颜料签名东海原。