Data from: Nutrient distribution and absorption in the colonial hydroid Podocoryna carnea is sequentially diffusive and directional

The distribution and absorption of ingested protein was characterized within a colony of Podocoryna carnea when a single polyp was fed. Observations were conducted at multiple spatial and temporal scales at three different stages of colony ontogeny with an artificial food item containing Texas Red conjugated albumin. Food pellets were digested and all tracer absorbed by digestive cells within the first 2–3 hours post-feeding. The preponderance of the label was located in the fed polyp and in a transport-induced diffusion pattern surrounding the fed polyp. After 6 hours post-feeding particulates re-appeared in the gastrovascular system and their absorption increased the area over which the nutrients were distributed, albeit still in a pattern that was centered on the fed polyp. At later intervals, tracer became concentrated in some stolon tips, but not in others, despite the proximity of these stolons either to the fed polyp or to adjacent stolons receiving nutrients. Distribution and absorption of nutrients is sequentially diffusive and directional.

本研究以单水螅体投喂为实验条件，对卡内薮枝螅（Podocoryna carnea）群落内摄入蛋白质的分布与吸收特征开展了表征分析。研究采用搭载德州红（Texas Red）偶联白蛋白的人工食物颗粒，在该群落发育的三个不同阶段，从多时空尺度进行了观测。投喂后2至3小时内，食物颗粒即被完全消化，所有示踪物均被消化细胞吸收。此时大部分示踪标记物集中于被投喂的水螅体，以及其周围由营养运输诱导形成的扩散分布格局中。投喂6小时后，胃血管系统（gastrovascular system）中重新出现颗粒状物质，该过程扩大了营养物质的分布范围，尽管分布格局仍以被投喂的水螅体为核心。在后续观测时段中，示踪物会富集于部分螅根（stolon）尖端，而非全部；即便这些螅根要么紧邻被投喂的水螅体，要么毗邻接收营养的相邻螅根。营养物质的分布与吸收过程呈现出先扩散、后定向的时序性特征。