Partial formation of sperm dimorphism from spermatocytes of the cottoid fish, Hemilepidotus gilberti in cell culture

Polymorphism of sperm is considered to be significant for the reproductive strategy in some animal species. The phenomenon is thought to occur in the species-specific stage of spermatogenesis, but how the identical germ cells are differentiated towards polymorphic sperm remains unknown. We here performed a germ cell culture in the cottoid fish, Hemilepidotus gilberti, whose sperm exhibit dimorphism with fertilizable eusperm and unfertilizable parasperm. In the culture, germ cells, which were obtained with an identical morphology, a spherical shape of 5-7 microm in diameter, differentiated into smaller spherical cells with a single nucleus, a moving flagellum and localized mitochondria. In addition, large retroflex-shaped cells with two elongated nuclei were also observed in the cell culture. Germ cells that had each morphological feature were histologically also observed in some cysts of the spermatogenetic testis, suggesting that the former type of cell corresponded to developing eusperm and the latter corresponded to developing parasperm. When BrdU was incorporated into germ cells in the culture, it was detected in both cells with eusperm-like and those with parasperm-like morphologies. These findings suggest that DNA-duplicating spermatocytes are potent to autonomously progress a part of spermatogenesis to form dimorphic sperm.     

Parasperm: morphological and functional studies on nonfertile sperm

Sperm polymorphism, a phenomenon in which more than one type of sperm is produced within a species, occurs widely in animals from invertebrates to vertebrates. Sperm in this phenomenon can be categorized into fertile sperm and nonfertile sperm on the basis of fertilization ability. Nonfertile sperm can be further classified into parasperm and aberrant deformed sperm. Parasperm are sperm produced through a constant developmental process along with normal fertile eusperm, and they are readily distinguished from deformed sperm, which are irregularly crippled by unpredictable errors at certain stages during spermatogenesis. Sperm identified as parasperm occur widely in invertebrates but are presently quite limited in vertebrates. This may be the result of the deficiency both of studies on parasperm and of clear criteria to identify parasperm in vertebrates. Some vertebrates show unique spermatogenesis, such as symplastic spermatid and semicystic spermatogenesis. Thus, parasperm must be identified by comparing cells in each cyst and in semen, because irregularly shaped cells in the seminal duct could be either parasperm or normal spermatids. Although parasperm are identified by clear criteria in vertebrates, only in cottoid fishes to date, it is possible for parasperm to be discovered in other vertebrates. Recently, roles related to sperm competition have been reported in several species (e.g., the marine cottoid fish Hemilepidotus gilberti), and, with some of them, parasperm production is influenced by an intraspecific factor such as a sex ratio or the density of a population. Sperm competition is one of the important candidates for influencing evolution of parasperm functions, but not all parasperm seem to have a relation to sperm competition. Parasperm function may relate to the ecological conditions of each species that produces parasperm. Studies on parasperm function will be advanced by an ecological approach concerning male fertilization success as well as cytological investigation for parasperm. An erratum to this article is available at .     

Ultrastructural observations of spermatozoa and spermiogenesis in Wandella orana Gray, 1994 (Araneae: Filistatidae) with notes on their phylogenetic implications

Spermatozoa and spermiogenesis of the prithine filistatid spider Wandella orana are described. The spider produces coenospermia, i.e. sperm aggregations that include several single sperm cells commonly surrounded by a secretion sheath. One sectioned coenospermium in W. orana contains at least five spermatozoa. During copulation many coenospermia are transferred into the female. Coenospermia are regarded as a peculiar transfer form of sperm which occurs in early derivative spiders such as Liphistiomorphae and Mygalomorphae. The only exception which was found in Araneomorphae until now was the filistatine spider Filistata insidiatrix. Our observation is the second case and supports the view that Filistatidae represent an early derivative taxon. Furthermore, the individual sperm cells show characteristics which also may be regarded as being plesiomorphic. There is a cone-shaped acrosomal vacuole, a very long acrosomal filament, a rather stout nucleus and a small implantation fossa. The axoneme shows the 9x2+3 pattern of microtubules which is synapomorphic in Megoperculata (Uropygi, Amblypygi and Araneae). The finding of coenospermia in two distant taxa of Filistatidae may have consequences for phylogenetic and systematic considerations.     

Functional deletion of Txndc2 and Txndc3 increases the susceptibility of spermatozoa to age-related oxidative stress

Oxidative stress in the male germ line is known to be a key factor in both the etiology of male infertility and the high levels of DNA damage encountered in human spermatozoa. Because the latter has been associated with a variety of adverse clinical outcomes, including miscarriage and developmental abnormalities in the offspring, the mechanisms that spermatozoa use to defend themselves against oxidative stress are of great interest. In this context, the male germ line expresses three unique forms of thioredoxin, known as thioredoxin domain-containing proteins (Txndc2, Txndc3, and Txndc8). Two of these proteins, Txndc2 and Txndc3, retain association with the spermatozoa after spermiation and potentially play an important role in regulating the redox status of the mature gamete. To address this area, we have functionally deleted the sperm-specific thioredoxins from the male germ line of mice by either exon deletion (Txndc2) or mutation of the bioactive cysteines (Txndc3). The combined inactivation of these Txndc isoforms did not have an overall impact on spermatogenesis, epididymal sperm maturation, or fertility. However, Txndc deficiency in spermatozoa did lead to age-dependent changes in these cells as reflected by accelerated motility loss, high rates of DNA damage, increases in reactive oxygen species generation, enhanced formation of lipid aldehyde–protein adducts, and impaired protamination of the sperm chromatin. These results suggest that although there is considerable redundancy in the systems employed by spermatozoa to defend themselves against oxidative stress, the sperm-specific thioredoxins, Txndc2 and Txndc3, are critically important in protecting these cells against the increases in oxidative stress associated with paternal age.     

The fine structure of spermiogenesis in the Amblypygi and the Uropygi (Arachnida)

Summary Spermiogenesis in one species from each of the arachnid groups Amblypygi and Uropygi is described by electron microscopy: The whip spider,Tarantula marginemaculata (Amblypygi), and the whip-scorpion,Mastigoproctus giganteus, (Uropygi). In both species the earliest spermatid has a spherical nucleus and soon acquires an anterior acrosome and a posterior flagellar tail. The flagellun is peculiar in having a 9 + 3 axonemal pattern. By the mid-spermatid stage, the nucleus becomes conspicuously elongated, possibly through the agency of a manchette of microtubules. In the late spermatid, the elongated nucleus begins to coil posteriorly; simultaneously the middle piece and the tail flagellum begin to retract into the cell body to form a coiled intracellular axonema. Membranous profiles appear in the peripheral cytoplasm, possibly to accommodate a decrease in the total area of plasma membrane. The mature sperm is a spherical cell, which includes the following organelles in twisted and fully coiled configuration: an elongated nucleus, an acrosome and an acrosomal filament, a long middle piece with helically arranged mitochondria and an intracellular axonema.     

Spermatozoa and spermiogenesis of Liphistius cf. phuketensis (Mesothelae, Araneae, Arachnida) with notes on phylogenetic implications

The present study deals with the spermatozoa and spermiogenesis of Liphistius cf. phuketensis, a representative of the most primitive and enigmatic spider group Mesothelae. The general organization of the spermatozoa is very similar to the condition known from Amblypygi supporting a sister-group relationship between Araneae and Amblypygi. Besides plesiomorphic characters such as, e.g., an elongated and corkscrew shaped nucleus, the sperm cells are characterized by several apomorphic characters, e.g., the giant body and conspicuous membranous areas which are formed at the end of spermiogenesis. As the transfer form, coenospermia are formed at the end of spermiogenesis, which strongly supports the idea that this type of sperm aggregation is the primitive transfer form within spiders. A very remarkable character of the spermatozoa of some groups of arachnids is the coiling of the main cell organelles at the end of spermiogenesis. Previously, the Mesothelae were believed to be the only spider group which does not show a complete coiling of the main cell organelles. With the present study the first evidence of a complete coiling of spermatozoa within this primitive spider group could be documented, indicating that this character is part of the ground pattern of spider spermatozoa. Consequently, the incomplete coiling seems to be a synapomorphy of certain species of Mesothelae, which sheds new light on the discussion of the phylogenetic relationships of this group.     

Sterols in spermatogenesis and sperm maturation

Mammalian spermatogenesis is a complex developmental program in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. One intriguing aspect of sperm production is the dynamic change in membrane lipid composition that occurs throughout spermatogenesis. Cholesterol content, as well as its intermediates, differs vastly between the male reproductive system and nongonadal tissues. Accumulation of cholesterol precursors such as testis meiosis-activating sterol and desmosterol is observed in testes and spermatozoa from several mammalian species. Moreover, cholesterogenic genes, especially meiosis-activating sterol-producing enzyme cytochrome P450 lanosterol 14α-demethylase, display stage-specific expression patterns during spermatogenesis. Discrepancies in gene expression patterns suggest a complex temporal and cell-type specific regulation of sterol compounds during spermatogenesis, which also involves dynamic interactions between germ and Sertoli cells. The functional importance of sterol compounds in sperm production is further supported by the modulation of sterol composition in spermatozoal membranes during epididymal transit and in the female reproductive tract, which is a prerequisite for successful fertilization. However, the exact role of sterols in male reproduction is unknown. This review discusses sterol dynamics in sperm maturation and describes recent methodological advances that will help to illuminate the complexity of sperm formation and function.     

The impact and potential etiology of teratospermia in the domestic cat and its wild relatives

Teratospermia (production of >60% morphologically abnormal sperm/ejaculate) is relatively common among various species in the family Felidae, which is comprised of 37 species. Over two decades of research in this area have produced a significant understanding of the phenotypic expression, its impacts on sperm function and etiology. There is good evidence suggesting that a reduction in genetic diversity contributes to this phenomenon. Results to date demonstrate that spermatozoa from teratospermic donors are compromised in the ability to undergo capacitation and the acrosome reaction, penetrate the zona-pellucida, fertilize conspecific oocytes and survive cryopreservation. Recent studies also reveal abnormalities in chromatin integrity in sperm from teratospermic donors, which, interestingly, fails to impact fertilization or embryo development after intracytoplasmic sperm injection. Through planned inbreeding studies, we now have established that teratospermic cats also produce more spermatozoa by virtue of more sperm producing tissue, more germ cells per Sertoli cell and reduced germ cell loss during spermatogenesis. Overall, it now is clear that gain in sperm quantity is achieved at the expense of sperm quality, suggesting an extensive disruption of normal testicular function in teratospermic donors. Preliminary studies on testicular gene expression in teratospermic cats have also revealed abnormal expression patterns. These findings have markedly increased our understanding of testis biology in the teratospermic donor and reaffirm the value of cats, including wild species, as models for studying novel regulatory mechanisms controlling spermatogenesis and spermiogenesis.     

The double sperm line in Isochaetides (Annelida,Clitellata, Tubificidae)

Sperm morphology and spermatogenesis were examined in the oligochaete annelid Isochaetides arenarius, a species belonging to the subfamily Tubificinae inhabiting the sediments of Lake Baikal. As all tubificines, Isochaetides produces two types of spermatozoa, named eusperm and parasperm. The eusperm are the fertilizing male gametes and consist, in sequence, of an acrosome, a nucleus, a mitochondrial mid-piece, and a tail. The parasperm have the same general architecture, but differ in cytological details: the acrosome is shorter, devoid of a perforatorium, and the acrosome vesicle has a different, simpler, shape. The nucleus is much shorter and rectilinear (the eusperm nucleus is twisted). The mid-piece mitochondria are less numerous but their overall volume is larger. The flagellum has a plasma membrane largely separated from the axoneme, and is devoid of glycogen granules. After mating, the two sperm types gather in the spermathecae to form spermatozeugmata; in these structures the parasperm form an external sheath involving the centrally located eusperm and their tails are connected by conspicuous septate junctions. Parasperm nuclei are produced through a process of fragmentation of the 'spermatocytes', whereas the flagellar basal bodies are produced by a process similar to that giving rise to basal bodies in ciliated epithelia.     

A phylogenetic analysis of Tubificinae and Limnodriloidinae (Annelida, Clitellata, Tubificidae) using sperm and somatic characters

Marotta, R., Ferraguti, M. & Erséus, C. (2003). A phylogenetic analysis of Tubificinae and Limnodriloidinae (Annelida, Clitellata, Tubificidae) using sperm and somatic characters. — Zoologica Scripta , 32 , 255–278.
The spermatozoa and the sperm aggregates of 13 species belonging to four genera ( Smithsonidrilus, Limnodriloides, Thalassodrilides, Doliodrilus ) in the tubificid subfamily Limnodriloidinae (Annelida, Oligochaeta) were studied and compared with the spermatozoal patterns already described in the subfamily Tubificinae. Two characters considered exclusive for the Tubificinae were found in the more spermatologically variable Limnodriloidinae: the production of two kinds of spermatozoa, eusperm and parasperm, and the presence, in the spermathecae, of sperm aggregates formed by a combination of the two sperm types. A parsimony analysis was performed on the spermatozoal data of the species examined and compared with that based on the somatic characters of the same species: a critical revision of the already codified eusperm characters was carried out and the ultrastructure of parasperm was used as a new subset of spermatozoal characters. In a total evidence approach, a further parsimony analysis was run using a matrix combining both sets of characters. This analysis suggested that the double sperm line and the sperm aggregates composed of both eusperm and parasperm may well be homologous in tubificines and limnodriloidines. It thus supported the previous notion that Tubificinae and Limnodriloidinae are closely related and indicated that these subfamilies may be sister taxa.     

Muscular anatomy of the giant whipscorpion Mastigoproctus giganteus (Lucas) (Arachnida: Uropygi) and its evolutionary significance

Skeletal muscles in the whipscorpion Mastigoproctus giganteus are surveyed and compared with those of several other to clarify the evolutionary morphology and phylogenetic relationships of arachnids. Representatives from 90 muscle groups are described and illustrated, and their possible functions are proposed. Principal results of this analysis include new proposed homologies for the anterior opisthosomal appendages and sclerites in tetrapulmonate arachnids (that is, Trigonotarbida, Araneae, Amblypygi, Uropygi), the discovery that muscular attachments in arthropods can shift from the mesodermal endosternite to the ectodermal exoskeleton, a reconstruction of the evolutionary transformations associated with the apparent uncoupling of pharyngeal and locomotor complexes in the prosoma of Pedipalpi (that is, Amblypygi and Uropygi), and an expanded list of unique synapomorphies supporting the sister-group status of Amblypygi and Uropygi.     

Sex and a snail's sperm: on the transport,storage and fate of dimorphic sperm in Littorinidae

Summary

Littorinid parasperm develop from a distinctive lineage of germ cells which exhibit a process of nuclear destruction that has apototic characteristics. Fragments of DNA and other nuclear breakdown products are incorporated into secretion granules in parasperm that ultimately find their way to the female bursa copulatrix. Spermatozeugmata are stored in the seminal vesicles and, if unused during the breeding season, they are recycled by phagocytosis. Attachment between eusperm and parasperm is facilitated by an electrostatic interaction of proteins. Detachment, caused by alkaline prostate fluid, occurs by the time the ejaculate reaches the tip of the penis. Thus transport of eusperm by parasperm to the female is unlikely. parasperm are sterile cells that may function in defense against rival eusperm as suggested by the presence of lysosomes, or they may act as nuptial gifts as they are packed with glycoprotein nutrients. Differences in the reactivity of different parasperm to specific lectins may enable separation of dimorphic sperm by lectin affinity chromatography, thereby facilitating future studies on individual parasperm. In female Littorinidae, sperm are stored incapacitated in storage organs, or rarely in the ovary itself. In L. littorea serotonin caused spawning of unencapsulated eggs, which, in the presence of activated sperm, became polyspermic.     

Obstructive Role of the Dimorphic Sperm in a Non-copulatory Marine Sculpin, Hemilepidotus gilberti, to Prevent Other Males' Eusperm from Fertilization

In many species of animals, males normally produce parasperm (dimorphic sperm) along with eusperm (normal sperm) during spermatogenesis. In the present study, to clarify the role of parasperm of the non-copulatory sculpin Hemilepidotus gilberti, whose reproduction is characterized by polyandrous oviposition involving sneaking by neighboring territorial males, we observed the movements of parasperm. Parasperm could not move by themselves, but they were transported in solutions by passive movement due to collisions with actively swimming eusperm. In the viscous ovarian fluid (OF), which isolates eggs from seawater by covering them during spawning, parasperm did not exhibit any movement. However, they could be transported by eusperm movement in solutions with dissolved OF, partly because the viscosity of the fluid become lower. And then, in some solutions parasperm formed lumps. Lump formation of parasperm was also observed at the boundary surface of an egg mass where OF contacted seawater. Eusperm added experimentally to a solution in which parasperm were forming lumps were engulfed in the lumps and never escaped. Thus, lump formation of parasperm would be obstacles for the later arriving eusperm. Although lumps formed against both kin and non-kin eusperm, parasperm are thought to be available to overcome sperm competition which would occur during spawning that involves sneaking being almost concurrent with lump formation. The territorial male eusperm reach the eggs while his parasperm hinder other males' eusperm from reaching the eggs. Thus, we concluded that parasperm of H. gilberti play a role on protection of paternity by blocking rival eusperm physically from approaching eggs.     

Colocalization of sulfogalactosylacylalkylglycerol (SGG) and its binding protein during spermatogenesis and sperm maturation. Topology of SGG defines a new testicular germ cell membrane domain

By use of double-labelling indirect immunofluorescence, we have shown that the major mammalian testicular glycolipid sulfogalactosylacylalkylglycerol (SGG) and a membrane protein, previously shown to bind specifically to SGG in vitro, are colocalized on the surface of rat testicular germ cells during spermatogenesis. SGG is restricted to convoluted membrane domains within these cells. Thus, the binding affinity in vitro is reflected in the cell surface topology. The topological relationship between these two antigens was also studied during epididymal sperm maturation. Whereas these antigens were colocalized in caput spermatozoa (on the middle and principal piece of the tail and on the concave surface of the head), the distribution of the binding protein was altered for cauda sperm in that the convex surface of the sperm head was now strongly labelled. These studies illustrate the dynamic nature of protein-glycolipid interactions during germ cell differentiation.     

Germ cell transplantation and testis tissue xenografting in domestic animals

Transplantation of germ cells from fertile donor mice to the testes of infertile recipient mice results in donor-derived spermatogenesis and transmission of the donor's genetic material to the offspring of recipient animals. Germ cell transplantation provides a bioassay to study the biology of male germ line stem cells, develop systems to isolate and culture spermatogonial stem cells, examine defects in spermatogenesis and treat male infertility. Although most widely studied in rodents, germ cell transplantation has been applied to larger mammals. In domestic animals including pigs, goats and cattle, as well as in primates, germ cells can be transplanted to a recipient testis by ultrasonographic-guided cannulation of the rete testis. Germ cell transplantation was successful between unrelated, immuno-competent pigs and goats, whereas transplantation in rodents requires syngeneic or immuno-compromised recipients. Genetic manipulation of isolated germ line stem cells and subsequent transplantation will result in the production of transgenic sperm. Transgenesis through the male germ line has tremendous potential in domestic animal species where embryonic stem cell technology is not available and current options to generate transgenic animals are inefficient. As an alternative to transplantation of isolated germ cells to a recipient testis, ectopic grafting of testis tissue from diverse mammalian donor species, including horses and primates, into a mouse host represents a novel possibility to study spermatogenesis, to investigate the effects of drugs with the potential to enhance or suppress male fertility, and to produce fertile sperm from immature donors. Therefore, transplantation of germ cells or xenografting of testis tissue are uniquely valuable approaches for the study, preservation and manipulation of male fertility in domestic animals.     

Temporal pattern of the double sperm line production in Tubifex tubifex (Annelida,Oligochaeta)

Laboratory cohort cultures of the tubificid Tubifex tubifexwere carried out at 21 °C in homogeneous conditions. Our aim was to study the temporal pattern of spermatogenesis of the two sperm lines which characterise this species. Starting from the second week after cocoon laying, we analysed the seminal vesicle content. We counted the cysts in the vesicles and arranged them into three classes: premeiotic, paraspermatids and euspermatids. Our results show that spermatogenesis begins early, at week 3, but cysts of spermatids are not found until week 5 for the parasperm line and week 6 for the eusperm line. These data are derived from a preliminary study of complex population dynamics. Nonetheless, they allow us to formulate some hypothesis regarding the mechanism which regulate the production of the two types of sperm.     

Sperm of Doradidae (Teleostei: Siluriformes)

Spermatic characteristics were studied in 10 species representing several distinct groups within the catfish family Doradidae. Interestingly, different types of spermatogenesis, spermiogenesis and spermatozoa are correlated with intrafamilial groups previously proposed for Doradidae. Semi-cystic spermatogenesis, modified Type III spermiogenesis, and biflagellate sperm appear to be unique within Doradidae to the subfamily Astrodoradinae. Other doradid species have sperm with a single flagellum, cystic spermatogenesis, and spermiogenesis of Type I (Pterodoras granulosus, Rhinodoras dorbignyi), Type I modified (Oxydoras kneri), or Type III (Trachydoras paraguayensis). Doradids have an external mode of fertilization, and share a few spermatic characteristics, such as cystic spermatogenesis, Type I spermiogenesis and uniflagellate sperm, with its sister group Auchenipteridae, a family exhibiting sperm modifications associated with insemination and internal fertilization. Semi-cystic spermatogenesis and biflagellate spermatozoa are also found in Aspredinidae, and corroborate recent proposals that Aspredinidae and Doradoidea (Doradidae + Auchenipteridae) are sister groups and that Astrodoradinae occupies a basal position within Doradidae. The co-occurrence in various catfish families of semi-cystic spermatogenesis and either biflagellate spermatozoa (Aspredinidae, Cetopsidae, Doradidae, Malapturidae, Nematogenyidae) or uniflagellate sperm with two axonemes (Ariidae) reinforces the suggestion that such characteristics are correlated. Semi-cystic spermatogenesis and biflagellate sperm may represent ancestral conditions for Loricarioidei and Siluroidei of Siluriformes as they occur in putatively basal members of each suborder, Nematogenyidae and Cetopsidae, respectively. However, if semi-cystic spermatogenesis and biflagellate sperm are ancestral for Siluriformes, cystic spermatogenesis and uniflagellate sperm have arisen independently in multiple lineages including Diplomystidae, sister group to Siluroidei.     

Transmission electron microscopy of impaired spermatogenesis in an avian hybrid

The mechanisms involved in the impaired spermatogenesis of male goldfinch x canary hybrids were investigated by transmission electron microscopy and compared with spermatogenesis in the testes of the parent species. In the parent species the testes were of normal structure, with the only unusual observation being that the Sertoli cells were variable in cytoplasmic electron density. In hybrid birds the Sertoli cells were either electron dense or electron lucent with respect to both nucleus and cytoplasm. In the hybrids examined in this study, no spermatozoa were produced. Spermatogenic stages were arrested without formation of synaptonemal complexes. Centrioles were abnormally arranged in both somatic and germ cells. When they moved away from the basement lamina the germ cells degenerated and were phagocytosed. No focal tight junctions were present between Sertoli cells overlying what would normally have been the basal compartment of the tubule. The basement lamina was unusually thickened, peritubular cells were abnormal in structure, and numerous plasma cells were present in the interstitial tissue. The observations reported here suggest that there was an immunological basis for degeneration of germ cells in the hybrid testis.     

Testicular,spermatogenesis and sperm morphology in Martarega bentoi (Heteroptera: Notonectidae)

The testicular, spermatogenesis and sperm morphology of the backswimmer Martarega bentoi was described using light and transmission electron microscopy. In this species, a pair of testes, two deferent ducts, two different pairs of accessory glands, and an ejaculatory duct form the male reproductive system. Each testis consists of two testicular follicles, which are arranged side by side in snail shape. The follicles are filled with cysts at different stages of spermatogenesis, but in the same cyst the germ cells (up to 64) are in the same stage. At the end of spermatogenesis, the sperm cells are very long, with the flagellum measuring approximately 2500 μm in length, the nucleus only 19 μm, and the acrosome, with two distinct regions, 300 μm. The flagellum is composed of an axoneme, with a 9 + 9 + 2 microtubular pattern, and 2 asymmetric mitochondrial derivatives (MDs). These have the anterior ends inserted into two cavities at the nucleus base, exhibit two paracrystalline inclusions, and have bridges linking them to the axoneme. Few spermatozoa per cyst, asymmetry in size and shape of the MDs, as well as their insertion at the nuclear base are characteristics considered derived, and that differentiate the sperm of M. bentoi from those of the Nepomorpha, Belostomatidae and Nepidae.     

中华蚱蜢精子发生过程中花生凝集素受体的分布与变化

采用生物素标记的花生凝集素(PNA)对中华蚱蜢(Acrida cinerea)精子发生过程中细胞质膜的糖蛋白(含有糖基Gal--β(1,3)-GalNAC)进行了标记,旨在认识精子发生过程中细胞质膜糖复合物的形成与变化规律,探讨其所具有的功能。结果表明,在中华蚱蜢的精子发生中,精母细胞能够自身合成PNA受体;精子细胞到成熟精子时期生精细胞质膜糖复合物发生了明显的修饰变化,这些变化与精子获得及卵子进行识别、粘附、结合等受精能力密切相关。