Developmental Dynamics of the Larval Muscle System of Bay Scallop(Argopecten irradians)  

作　　者：SUN Xiujun LIU Zhihong ZHOU Liqing WU Biao YANG Aiguo TIAN Jiteng 

机构地区：[1]Key Laboratory of Sustainable Development of Marine Fisheries of Ministry of Agriculture and Rural Affairs,Yellow Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Qingdao 266071,China [2]Function Laboratory for Marine Fisheries Science and Food Production Processes,Pilot National Laboratory for Marine Science and Technology,Qingdao 266071,China

出　　处：《Journal of Ocean University of China》2020年第2期386-392,共7页中国海洋大学学报（英文版）

基　　金：supported by research grants from the National Key R&D Program of China(No.2018YFD0900104);the Na-tional Natural Science Foundation of China(No.3160 2153);the Central Public-Interest Scientific Institution Basal Research Fund,YSFRI,CAFS(No.20603022019 005);Qingdao People’s Livelihood Science and Tech-nology Project(No.18-6-1-110-nsh)

摘　　要：Though the larval development of bivalves has been extensively studied for commercial purposes,the dynamic development of larval muscle system remains largely unknown.In this study,we characterized the larval muscle system at different developmental stages(D-shaped veligers,umbo veligers and spats)in the bay scallop(Argopecten irradians)by phalloidin staining and under a confocal microscopy.The functional muscles are initially established at the early stage of veligers,which have four pairs of velar retractors and one anterior adductor.At the veliger stage,the velum and posterior retractor muscles are functionally important for velar contractility but undergo an irreversible shrink until they disappear at the end of the larval stage.During metamorphosis,three crucial modifications take place in the larval muscle system.The metamorphosis process involves the gradual degeneration of velum retractors,mantle margin development from an unfolded to a three-fold state,and remodeling of the adductor muscle system from dimyarian(two adductors)to monomyarian condition(one adductor)as in juveniles/adults.All retractor muscles are composed of striated muscle,but both anterior and posterior adductors have smooth and striated components.These findings highlight that the morphological changes at different stages are typical features of myogenesis in scallops.The present knowledge on the developmental dynamics of myogenesis in the bay scallop will not only improve our understanding of phenotypic diversity of larval myoanatomy in bivalves,but also provide useful information on the larval culture in hatcheries.Though the larval development of bivalves has been extensively studied for commercial purposes, the dynamic development of larval muscle system remains largely unknown. In this study, we characterized the larval muscle system at different developmental stages(D-shaped veligers, umbo veligers and spats) in the bay scallop(Argopecten irradians) by phalloidin staining and under a confocal microscopy. The functional muscles are initially established at the early stage of veligers, which have four pairs of velar retractors and one anterior adductor. At the veliger stage, the velum and posterior retractor muscles are functionally important for velar contractility but undergo an irreversible shrink until they disappear at the end of the larval stage. During metamorphosis, three crucial modifications take place in the larval muscle system. The metamorphosis process involves the gradual degeneration of velum retractors, mantle margin development from an unfolded to a three-fold state, and remodeling of the adductor muscle system from dimyarian(two adductors) to monomyarian condition(one adductor) as in juveniles/adults. All retractor muscles are composed of striated muscle, but both anterior and posterior adductors have smooth and striated components. These findings highlight that the morphological changes at different stages are typical features of myogenesis in scallops. The present knowledge on the developmental dynamics of myogenesis in the bay scallop will not only improve our understanding of phenotypic diversity of larval myoanatomy in bivalves, but also provide useful information on the larval culture in hatcheries.

关 键 词：MYOGENESIS retractor muscle METAMORPHOSIS adductor muscle 

分 类 号：S917.4[农业科学—水产科学]