scholarly journals EVOLUTION OF MULTIPLE KINDS OF FEMALE SPERM-STORAGE ORGANS INDROSOPHILA

Evolution ◽  
1999 ◽  
Vol 53 (6) ◽  
pp. 1804-1822 ◽  
Author(s):  
Scott Pitnick ◽  
Therese Marrow ◽  
Greg S. Spicer
Keyword(s):  
Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 289
Author(s):  
Gurman Grewal ◽  
Bahar Patlar ◽  
Alberto Civetta

In Drosophila, male reproductive fitness can be affected by any number of processes, ranging from development of gametes, transfer to and storage of mature sperm within the female sperm storage organs, and utilization of sperm for fertilization. We have previously identified the 89B cytogenetic map position of D. melanogaster as a hub for genes that effect male paternity success when disturbed. Here, we used RNA interference to test 11 genes that are highly expressed in the testes and located within the 89B region for their role in sperm competition and male fecundity when their expression is perturbed. Testes-specific knockdown (KD) of bor and CSN5 resulted in complete sterility, whereas KD of CG31287, Manf and Mst89B, showed a breakdown in sperm competitive success when second to mate (P2 < 0.5) and reduced fecundity in single matings. The low fecundity of Manf KD is explained by a significant reduction in the amount of mature sperm produced. KD of Mst89B and CG31287 does not affect sperm production, sperm transfer into the female bursa or storage within 30 min after mating. Instead, a significant reduction of sperm in female storage is observed 24 h after mating. Egg hatchability 24 h after mating is also drastically reduced for females mated to Mst89B or CG31287 KD males, and this reduction parallels the decrease in fecundity. We show that normal germ-line expression of Mst89B and CG31287 is needed for effective sperm usage and egg fertilization.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Lenka Sentenská ◽  
Aileen Neumann ◽  
Yael Lubin ◽  
Gabriele Uhl

Abstract Background Mating generally occurs after individuals reach adulthood. In many arthropods including spiders, the adult stage is marked by a final moult after which the genitalia are fully developed and functional. In several widow spider species (genus Latrodectus), however, immature females may mate a few days before they moult to adulthood, i.e. in their late-subadult stage. While the “adult” mating typically results in cannibalism, males survive the “immature” mating. During both “immature” and “adult” matings, males leave parts of their paired copulatory organs within female genitalia, which may act as mating plugs. To study potential costs and benefits of the two mating tactics, we investigated female genital morphology of the brown widow spider, L. geometricus. Light microscopy, histology and micro-computed tomography of early-subadult, late-subadult and adult females were conducted to determine the overall pattern of genital maturation. We compared genitalia of mated late-subadult and adult females to reveal potential differences in the genitalic details that might indicate differential success in sperm transfer and different environments for sperm storage and sperm competition. Results We found that the paired sperm storage organs (spermathecae) and copulatory ducts are developed already in late-subadult females and host sperm after immature mating. However, the thickness of the spermathecal cuticle and the staining of the secretions inside differ significantly between the late-subadult and adult females. In late-subadult females mating plugs were found with higher probability in both spermathecae compared to adult females. Conclusions Sperm transfer in matings with late-subadult females follows the same route as in matings with adult females. The observed differences in the secretions inside the spermathecae of adult and late-subadult females likely reflect different storage conditions for the transferred sperm which may lead to a disadvantage under sperm competition if the subadult female later re-mates with another male. However, since males mating with late-subadult females typically transfer sperm to both spermathecae they might benefit from numerical sperm competition as well as from monopolizing access to the female sperm storage organs. The assessment of re-mating probability and relative paternity will clarify the costs and benefits of the two mating tactics in light of these findings.


2020 ◽  
pp. 332-363
Author(s):  
Carola Becker ◽  
Raymond T. Bauer

In polyandrous mating systems, females mate multiple times and males have evolved adaptations for sperm competition which increase the number and fitness of their offspring. Mate guarding is a widespread monopolization strategy in groups where female receptivity is temporally restricted and often associated with the molt. Precopulatory guarding occurs in branchipods, copepods, peracarids and decapods. Postcopulatory guarding is notable in numerous brachyurans with males protecting females until her exoskeleton has hardened. During copulation, male success in fertilization depends on an effective sperm transfer mechanism, the precise placement of ejaculates closest to where female gametes are fertilized. Male copulatory systems are highly diverse and strongly adapted to these tasks, especially the structures that interact with the female genital ducts. The elaborate tips of brachyuran gonopods are supposed to act in the displacement, possibly even in the removal of rival sperm masses; however, sperm removal is only evident in crayfish: males eat spermatophores previously deposited by other males. During copulation of several crustacean groups, males transfer secretions that harden and form a sealant. These sperm plugs, plaques and gel layers may protect their own sperm, prevent remating or seal off rival sperm from the site of fertilization. Several groups of isopods and decapods have internal insemination, elaborate sperm storage organs and some exhibit internal fertilization. The intensity of sperm competition increases with the latency between the processes of insemination and fertilization. This chapter gives on overview on mate guarding, male sealants and the anatomical adaptations to sperm competition in crustaceans. We also briefly discuss the consequences of multiple matings for the genetic diversity of broods, i.e., single vs. multiple paternities. There is still a lack of data for many crustacean groups. Moreover, it is often hard to assess how successful a male strategy to ensure paternity actually is as many studies focus on either the behavioral, anatomical, or molecular aspects, while comprehensive multi-level studies on crustacean sperm competition are virtually absent from the literature.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Tatsuro Konagaya ◽  
Naoto Idogawa ◽  
Mamoru Watanabe

AbstractMost male lepidopterans produce fertile eupyrene sperm and non-fertile apyrene sperm, both of which are transferred to the female in a spermatophore during mating. Apyrene sperm outnumbers eupyrene sperm and both sperm types migrate from the bursa copulatrix to the spermatheca after mating. While eupyrene sperm are maintained in the spermatheca until oviposition, the number of apyrene sperm decreases with time. It is unclear whether apyrene sperm disappear from all sperm storage organs in females because both sperm types are often observed in the spermathecal gland. To investigate this, the numbers of both sperm types were estimated in the spermatheca and spermathecal gland of female Byasa alcinous (a monandrous butterfly) 6, 12, 48, 96, and 192 h after mating terminated. Apyrene sperm arrived in the spermatheca earlier than eupyrene sperm; however, some eupyrene and apyrene sperm migrated to the spermathecal gland from the spermatheca at almost the same time. The number of apyrene sperm reached a peak 12 h after the termination of mating and then decreased with time in both the spermatheca and spermathecal gland. Our results suggest that the role of apyrene sperm might be completed early after arriving in the spermatheca of B. alcinous.


2019 ◽  
Vol 70 (4) ◽  
pp. 301-311
Author(s):  
János Szabad ◽  
Jing Peng ◽  
Eric Kubli

Introduction In this study, we analyzed gynandromorphs with female terminalia, to dissect mating-related female behaviors in Drosophila. Materials and methods We used gynandromorphs, experimentally modified wild-type (Oregon-R) females, and mutant females that lacked different components of the female reproductive apparatus. Results Many of the gynandromorphs mated but did not expel the mating plug (MP). Some of these – with thousands of sperm in the uterus – failed to take up sperm into the storage organs. There were gynandromorphs that stored plenty of sperm but failed to release them to fertilize eggs. Expelling the MP, sperm uptake into the storage organs, and the release of stored sperm along egg production are separate steps occurring during Drosophila female fertility. Cuticle landmarks of the gynandromorphs revealed that while the nerve foci that control MP expelling and also those that control sperm uptake reside in the abdominal, the sperm release foci derive from the thoracic region of the blastoderm. Discussion and conclusion The gynandromorph study is confirmed by analyses of (a) mutations that cause female sterility: Fs(3)Avar (preventing egg deposition), Tm2gs (removing germline cells), and iab-4DB (eliminating gonad formation) and (b) by experimentally manipulated wild-type females: decapitated or cut through ventral nerve cord.


2009 ◽  
Vol 106 (37) ◽  
pp. 15796-15800 ◽  
Author(s):  
Frank W. Avila ◽  
Mariana F. Wolfner

In a multitude of animals with internal fertilization, including insects and mammals, sperm are stored within a female's reproductive tract after mating. Defects in the process of sperm storage drastically reduce reproductive success. In Drosophila males, “Acp” seminal proteins alter female postmating physiology and behavior, and are necessary for several aspects of sperm storage. For example, Acps cause a series of conformational changes in the mated female's reproductive tract that occur during and immediately after mating. These conformational changes have been hypothesized to aid both in the movement of sperm within the female and in the subsequent storage of those sperm. We used RNAi to systematically knock down several Acps involved in sperm storage to determine whether they played a role in the mating-induced uterine conformational changes. Mates of males lacking the glycoprotein Acp36DE, which is needed for the accumulation of sperm in the storage organs, fail to complete the full sequence of the conformational changes. Our results show that uterine conformational changes are important for proper accumulation of sperm in storage and identify a seminal protein that mediates these changes. Four Acps included in this study, previously shown to affect sperm release from storage (CG9997, CG1656, CG1652, and CG17575), are not necessary for uterine conformational changes to occur. Rather, consistent with their role in later steps of sperm storage, we show here that their presence can affect the outcome of sperm competition situations.


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