Müller Werner E G, Wendt Klaus, Geppert Christopher, Wiens Matthias, Reiber Andreas, Schröder Heinz C
Institut für Physiologische Chemie, Abteilung Angewandte Molekularbiologie, Universität, Duesbergweg 6, D-55099 Mainz, Germany.
Biosens Bioelectron. 2006 Jan 15;21(7):1149-55. doi: 10.1016/j.bios.2005.04.017. Epub 2005 Jun 2.
Sponges (phylum Porifera) of the classes Hexactinellida and Demospongiae possess a skeleton composed of siliceous spicules, which are synthesized enzymatically. The longest spicules are found among the Hexactinellida, with the stalk spicules (length: 30 cm; diameter: 300 microm) of Hyalonema sieboldi as prominent examples. These spicules are constructed around a central axial filament, which is formed by approximately 40 siliceous layers. The stratified spicules function as optical glass fibers with unique properties. If free-spaced coupled with a white light source (WLS), the entire fiber is illuminated. Special features of the light transmission: (i) only wavelengths between 615 and 1310 nm can pass through the fibers and (ii) light below wavelengths of 615 nm and above 1310 nm is completely cut-off. The transmission efficiency is around 60% (measured at 1080-1100 nm [length of the fiber: 5 cm]). The spicules acts as sharp high- and low-pass filters, suggesting that these silica-based fibers might be involved in a photoreception system. This assumption is supported by the finding that sponges are provided with a bioluminescent system. It is hypothesized that the spicules/siliceous fibers might be involved in a photoreception system in these animals.
六放海绵纲和寻常海绵纲的海绵动物（多孔动物门）具有由硅质骨针组成的骨架，这些骨针是通过酶促合成的。最长的骨针见于六放海绵纲，以赛氏偕老同穴的柄状骨针（长度：30厘米；直径：300微米）为显著例子。这些骨针围绕着一根中央轴丝构建，该轴丝由大约40层硅质层形成。分层的骨针起到具有独特性质的光学玻璃纤维的作用。如果与白光源（WLS）自由空间耦合，整个纤维会被照亮。光传输的特点：（i）只有波长在615至1310纳米之间的光可以穿过纤维，（ii）波长低于615纳米和高于1310纳米的光被完全截止。传输效率约为60%（在1080 - 1100纳米处测量[纤维长度：5厘米]）。骨针起到尖锐的高通和低通滤波器的作用，这表明这些基于二氧化硅的纤维可能参与了光接收系统。这一假设得到了海绵动物具有生物发光系统这一发现的支持。据推测，骨针/硅质纤维可能参与了这些动物的光接收系统。
