Shah Mujahid Ali, Xie Xuan, Rodina Marek, Stundl Jan, Braasch Ingo, Šindelka Radek, Rzepkowska Małgorzata, Saito Taiju, Pšenička Martin
Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in Ceske Budejovice, Vodnany, Czechia.
Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States.
Front Cell Dev Biol. 2024 May 30;12:1358702. doi: 10.3389/fcell.2024.1358702. eCollection 2024.
In vertebrates, maternally supplied yolk is typically used in one of two ways: either intracellularly by endodermal cells or extracellularly via the yolk sac. This study delves into the distinctive gut development in sturgeons, which are among the most ancient extant fish groups, contrasting it with that of other vertebrates. Our observations indicate that while sturgeon endodermal cells form the archenteron (i.e., the primitive gut) dorsally, the floor of the archenteron is uniquely composed of extraembryonic yolk cells (YCs). As development progresses, during neurulation, the archenteric cavity inflates, expands laterally, and roofs a semicircle of YCs. By the pharyngula stage, the cavity fully encompasses the YC mass, which begins to be digested at the hatching stage. This suggests a notable deviation in sturgeon gut development from that in other vertebrates, as their digestive tract initiates its function by processing endogenous nutrition even before external feeding begins. Our findings highlight the evolutionary diversity of gut development strategies among vertebrates and provide new insights into the developmental biology of sturgeons.
在脊椎动物中，母体提供的卵黄通常以两种方式之一被利用：要么由内胚层细胞在细胞内利用，要么通过卵黄囊在细胞外利用。本研究深入探讨了鲟鱼独特的肠道发育，鲟鱼是现存最古老的鱼类群体之一，并将其与其他脊椎动物的肠道发育进行对比。我们的观察表明，虽然鲟鱼的内胚层细胞在背侧形成原肠（即原始肠道），但原肠的底部独特地由胚外卵黄细胞（YCs）组成。随着发育的进行，在神经胚形成期间，原肠腔膨胀，向侧面扩展，并覆盖了一圈半圆形的卵黄细胞。到咽胚期，腔完全包围了卵黄细胞团，卵黄细胞团在孵化期开始被消化。这表明鲟鱼的肠道发育与其他脊椎动物有显著差异，因为它们的消化道甚至在开始外部摄食之前就通过处理内源性营养来启动其功能。我们的发现突出了脊椎动物肠道发育策略的进化多样性，并为鲟鱼的发育生物学提供了新的见解。
