University of Hawaii, Kewalo Marine Laboratory, Honolulu, HI 96813, USA.
J Exp Biol. 2021 Oct 15;224(20). doi: 10.1242/jeb.242300. Epub 2021 Oct 20.
Larvae of many marine invertebrates bear an anteriorly positioned apical sensory organ (ASO) presumed to be the receptor for settlement- and metamorphosis-inducing environmental cues, based on its structure, position and observed larval behavior. Larvae of the polychaete Hydroides elegans are induced to settle by bacterial biofilms, which they explore with their ASO and surrounding anteroventral surfaces. A micro-laser was utilized to destroy the ASO and other anterior ciliary structures in competent larvae of H. elegans. After ablation, larvae were challenged with bacterial biofilmed or clean surfaces and percentage metamorphosis was determined. Ablated larvae were also assessed for cellular damage by applying fluorescently tagged FMRF-amide antibodies and observing the larvae by laser-scanning confocal microscopy. While the laser pulses caused extensive damage to the ASO and surrounding cells, they did not inhibit metamorphosis. We conclude that the ASO is not a required receptor site for cues that induce metamorphosis.
许多海洋无脊椎动物的幼虫具有一个位于前端的顶生感觉器官（ASO），根据其结构、位置和观察到的幼虫行为，该器官被认为是感应定居和变态诱导环境信号的受体。多毛类海生环节动物秀丽仙台虫的幼虫被细菌生物膜诱导定居，它们用 ASO 和周围的前腹面来探索这些生物膜。我们利用微激光来破坏秀丽仙台虫有能力的幼虫的 ASO 和其他前纤毛结构。在消融后，用附有细菌生物膜的或干净的表面来挑战幼虫，并确定变态的百分比。通过应用荧光标记的 FMRF-amide 抗体并通过激光共聚焦扫描显微镜观察幼虫，评估消融后的幼虫是否有细胞损伤。虽然激光脉冲对 ASO 和周围细胞造成了广泛的损伤，但它们并没有抑制变态。我们得出结论，ASO 不是诱导变态的信号所必需的受体位点。
