Abstract
BackgroundThe Chinese mitten crab Eriocheir sinensis belongs to the Class Crustacea, Decapoda, Brachyura. The spermatozoon of this species is of aflagellated type, it has a spherical acrosome surrounded by the cup-shaped nucleus, which are unique to brachyurans. For the past several decades, studies on the spermatogenesis of the mitten crab mainly focus on the morphology. Compared with the extensive study of molecular mechanism of spermatogenesis in mammals, relatively less information is available in crustacean species. Myosin Va, a member of Class V myosin, has been implicated in acrosome biogenesis and vesicle transport during spermatogenesis in mammals. In the present study we demonstrate the expression and cellular localization of myosin Va during spermatogenesis in E. sinensis.Methodology/Principal FindingsWestern blot demonstrated that myosin Va is expressed during spermatogenesis. Immunocytochemical and ultrastructural analyses showed that myosin Va mainly localizes in the cytoplasm in spermatocytes. At the early stage of spermiogenesis, myosin Va binds to the endoplasmic reticulum vesicle (EV) and proacrosomal granule (PG). Subsequently, myosin Va localizes within the proacrosomal vesicle (PV) formed by PG and EV fusion and locates in the membrane complex (MC) at the mid spermatid stage. At the late spermatid stage, myosin Va is associated with the shaping nucleus and mitochondria. In mature spermatozoon, myosin Va predominates in acrosomal tubule (AT) and nucleus.Conclusions/SignificanceOur study demonstrates that myosin Va may be involved in acrosome biogenesis and nuclear morphogenesis during spermatogenesis in E. sinensis. Considering the distribution and molecular characteristics of myosin Va, we also propose a hypothesis of AT formation in this species. It is the first time to uncover the role of myosin Va in crustacean spermatogenesis.
Highlights
Spermatogenesis refers to the process which diploid spermatogonia develop into haploid mature spermatozoa
The antibody recognized a band about 215 kDa expected for myosin Va in the brain lysate of mice, a similar immunoreactive band was indentified in testicular lysate of E. sinensis (Figure 2)
Myosin Va is localized in the manchette and associated with manchette vesicles, indicating that it participates in the intramanchette transport [10,41]
Summary
Spermatogenesis refers to the process which diploid spermatogonia develop into haploid mature spermatozoa. It can be divided into three phases: the mitotic phase, meiotic phase, and spermiogenesis phase. Spermatids differentiate into well shaped spermatozoa through organelle reorganization and new structure formation [1,2]. Three major events occur during spermiogenesis in mammals, i.e., nuclear condensation, acrosomal shaping, and mid-piece formation. The Chinese mitten crab Eriocheir sinensis belongs to the Class Crustacea, Decapoda, Brachyura. The spermatozoon of this species is of aflagellated type, it has a spherical acrosome surrounded by the cup-shaped nucleus, which are unique to brachyurans. In the present study we demonstrate the expression and cellular localization of myosin Va during spermatogenesis in E. sinensis
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
