Schnitzler Christine E, Keenan Robert J, McCord Robert, Matysik Artur, Christianson Lynne M, Haddock Steven H D
Monterey Bay Aquarium Research Institute, 7700 Sandholdt Rd, Moss Landing, CA 95039, USA.
Mar Biotechnol (NY). 2008 May-Jun;10(3):328-42. doi: 10.1007/s10126-007-9072-7. Epub 2008 Mar 11.
Color morphs of the temperate, nonsymbiotic corallimorpharian Corynactis californica show variation in pigment pattern and coloring. We collected seven distinct color morphs of C. californica from subtidal locations in Monterey Bay, California, and found that tissue- and color-morph-specific expression of at least six different genes is responsible for this variation. Each morph contains at least three to four distinct genetic loci that code for these colors, and one morph contains at least five loci. These genes encode a subfamily of new GFP-like proteins, which fluoresce across the visible spectrum from green to red, while sharing between 75% to 89% pairwise amino-acid identity. Biophysical characterization reveals interesting spectral properties, including a bright yellow protein, an orange protein, and a red protein exhibiting a "fluorescent timer" phenotype. Phylogenetic analysis indicates that the FP genes from this species evolved together but that diversification of anthozoan fluorescent proteins has taken place outside of phylogenetic constraints, especially within the Corallimorpharia. The discovery of more examples of fluorescent proteins in a non-bioluminescent, nonsymbiotic anthozoan highlights possibilities of adaptive ecological significance unrelated to light regulation for algal symbionts. The patterns and colors of fluorescent proteins in C. californica and similar species may hold meaning for organisms that possess the visual pigments to distinguish them.
温带非共生珊瑚藻Corynactis californica的颜色变体在色素模式和颜色上表现出差异。我们从加利福尼亚州蒙特雷湾的潮下带位置收集了七种不同颜色变体的C. californica，发现至少六种不同基因的组织和颜色变体特异性表达导致了这种差异。每个变体至少包含三到四个编码这些颜色的不同基因座，其中一个变体至少包含五个基因座。这些基因编码一个新的类绿色荧光蛋白（GFP）亚家族，它们在从绿色到红色的可见光谱范围内发出荧光，同时氨基酸序列两两之间的相似度在75%到89%之间。生物物理特性揭示了有趣的光谱特性，包括一种亮黄色蛋白、一种橙色蛋白和一种表现出“荧光定时器”表型的红色蛋白。系统发育分析表明，该物种的荧光蛋白（FP）基因共同进化，但珊瑚虫荧光蛋白的多样化发生在系统发育限制之外，尤其是在珊瑚藻目内。在一种非生物发光、非共生的珊瑚虫中发现更多荧光蛋白的例子，凸显了与藻类共生体的光调节无关的适应性生态意义的可能性。C. californica和类似物种中荧光蛋白的模式和颜色可能对拥有视觉色素以区分它们的生物体具有意义。
