Morphological and morphometrical assessment of spermathecae of Aedes aegypti females

Pascini, Tales Vicari; Ramalho-Ortigão, Marcelo; Martins, Gustavo Ferreira

doi:10.1590/s0074-02762012000600001

Cited by 27 publications

(31 citation statements)

References 37 publications

(55 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…SCs discharge their secretions to the central lumen through the end-apparatus and the canal, all of which make up the secretory unit. Similar secretory units are also found in Drosophila parovaria (Allen and Spradling 2008) and spermathecae of cockroaches (Gupta and Smith 1969), mealworms (Happ and Happ 1977), Rhodnius (Lococo and Huebner 1980), springtails (Dallai et al 2008), and mosquitoes (Pascini et al 2012, 2013; Laghezza Masci et al 2015). This type of secretory units is also found in epidermal glands, which are categorized into three classes according to the morphology of the SC and the way of discharge of the secretion (Noirot and Quennedey 1974).…”

supporting

confidence: 57%

Dynamic Notch Signaling Specifies Each Cell Fate inDrosophilaSpermathecal Lineage

Shen

Sun

2017

G3 Genes|Genomes|Genetics

View full text Add to dashboard Cite

Spermathecae are glandular organs in the insect female reproductive tract that play essential roles in insect reproduction; however, the molecular mechanism involved in their development is largely unknown. Drosophila spermathecae consist of class-III secretory units, in which each secretory cell (SC) discharges its products to the central lumen through an end-apparatus and a canal. Secretory unit formation in Drosophila spermathecae utilizes a fixed cell lineage, in which each secretory unit precursor (SUP) divides to produce one pIIb cell and one pIIa cell. The former differentiates into an apical cell (AC), whereas the latter divides again to produce an SC and a basal cell (BC). It is unclear how each cell acquires its identity and contributes to secretory unit formation. Here, we demonstrate that Notch signaling is required and sufficient for the specification of lumen epithelial precursors (LEPs; vs. SUPs), pIIb (vs. pIIa), and SCs (vs. BCs) sequentially. To our surprise, Notch activation in LEPs and SCs apparently utilizes different ligand mechanisms. In addition, Notch signaling both suppresses and activates transcription factors Hindsight (Hnt) and Cut during spermathecal lineage specification, supporting the notion that Notch signaling can have opposite biological outcomes in different cellular environments. Furthermore, LEP-derived epithelial cells (ECs) and ACs show distinct cellular morphology and are essential for securing secretory units to the epithelial lumen. Our work demonstrates, for the first time, the dynamic role of Notch signaling in binary cell fate determination in Drosophila spermathecae and the role of ECs and ACs in secretory unit formation. KEYWORDSclass-III secretory gland spermathecae Notch signaling binary cell fate determination Cut Spermathecae are sperm-storage organs found in the female reproductive tract of many insect species, and they are important for reproduction and cryptic female choice (Eberhard 1996;Pitnick et al. 1999;Manier et al. 2010). Studies in Drosophila have shown that glandular secretions from spermathecae and parovaria act to attract, nourish, and protect sperm by creating an appropriate environment (Filosi and Perotti 1975;Allen and Spradling 2008;Prokupek et al. 2008Prokupek et al. , 2009Schnakenberg et al. 2011;Sun and Spradling 2013). This is likely true in other insect species (Shaw et al. 2014). In addition, glandular secretions from spermathecae and parovaria regulate ovulation and egg laying (Schnakenberg et al. 2011;Sun and Spradling 2013;Cattenoz et al. 2016). Although the exact identities of the secreted products regulating sperm and ovulation are unknown, it is clear that secretions through the canonical protein secretory pathway are required for sperm storage but not ovulation (Sun and Spradling 2013). Despite recent progress on the physiology of spermatheca secretion, the molecular mechanisms involved in spermathecal gland formation are largely unknown.Spermathecae in Drosophila melanogaster are a pair of mushroomshaped organs with a h...

show abstract

supporting

confidence: 57%

Dynamic Notch Signaling Specifies Each Cell Fate inDrosophilaSpermathecal Lineage

Shen

Sun

2017

G3 Genes|Genomes|Genetics

View full text Add to dashboard Cite

show abstract

“…The spermathecae are chitinous, spherical reservoirs in which sperm are stored long‐term. Sperm are maintained in these capsules for a female's entire life, nourished by glandular cells adjoining the spermathecae (Clements and Potter, ; Pascini et al, , ). Ultimately, sperm travel back down these same ducts and fertilize eggs that pass down the common oviduct and out the gonotreme (Fig.…”

Section: Reproductive Tract Morphologymentioning

confidence: 99%

“…Getting sperm to the spermathecal vestibule may be accomplished by chemotaxis, consistent with the results of Pitts et al (), which demonstrated chemical activation of sperm in response to different ligands. Possible origins of the stimulus responsible for localization to the vestibule include the female accessory gland, the spermathecal duct glands, or the spermathecal glands (Clements and Potter, ; Pascini et al, , ). Yet Jones and Wheeler () discounted all three possibilities, as they did not observe any in vitro activation of sperm in response to these organs—although these observations should be verified in vivo to truly understand sperm activation.…”

Section: Sperm Aggregation At the Spermathecal Vestibulementioning

confidence: 99%

“…These cells connect to the lumen of the spermatheca via ductules, and form a gland situated around the juncture of the spermathecal duct and capsule. Their ultrastructure has been extensively characterized by both light and electron microscopy in A. aegypti and A. aquasalis (Clements and Potter, ; Pascini et al, , ). The secretions of these glands have not been examined directly in mosquitoes, but proteomic studies of the spermathecal fluid in the honey bee, A. mellifera , may provide insight to mosquito spermathecal function.…”

Section: Maintenance and Storage In The Spermathecaementioning

confidence: 99%

See 1 more Smart Citation

A mosquito sperm's journey from male ejaculate to egg: Mechanisms, molecules, and methods for exploration

Degner

Harrington

2016

Molecular Reproduction Devel

View full text Add to dashboard Cite

SUMMARYThe fate of mosquito sperm in the female reproductive tract has been addressed sporadically and incompletely, resulting in significant gaps in our understanding of sperm‐female interactions that ultimately lead to fertilization. As with other Diptera, mosquito sperm have a complex journey to their ultimate destination, the egg. After copulation, sperm spend a short time at the site of insemination where they are hyperactivated and quickly congregate near the entrance of the spermathecal ducts. Within minutes, they travel up the narrow ducts to the spermathecae, likely through the combined efforts of female transport and sperm locomotion. The female nourishes sperm and maintains them in these permanent storage organs for her entire life. When she is ready, the female coordinates the release of sperm with ovulation, and the descending egg is fertilized. Although this process has been well studied via microscopy, many questions remain regarding the molecular processes that coordinate sperm motility, movement through the reproductive tract, maintenance, and usage. In this review, we describe the current understanding of a mosquito sperm's journey to the egg, highlighting gaps in our knowledge of mosquito reproductive biology. Where insufficient information is available in mosquitoes, we describe analogous processes in other organisms, such as Drosophila melanogaster, as a basis for comparison, and we suggest future areas of research that will illuminate how sperm successfully traverse the female reproductive tract. Such studies may yield molecular targets that could be manipulated to control populations of vector species. Mol. Reprod. Dev. 83: 897–911, 2016. © 2016 The Authors. Molecular Reproduction and Development Published by Wiley Periodicals, Inc.

show abstract

“…aegypti, there are three functional spermathecae: a large spermatheca that is centrally located, and two smaller, laterally positioned spermathecae. Both large and small spermathecae are morphologically similar with regards to cell types and gross organization [10,11], each one comprised of a long duct (responsible for guiding the sperm migration), a rounded reservoir or capsule (for sperm storage), and a glandular portion (that produces and secretes compounds used for sperm storage and nourishment). Glandular cells (GC) present in the reservoir and in the duct form the glandular portion.…”

Section: Introductionmentioning

confidence: 99%

Transcriptional profiling and physiological roles of Aedes aegypti spermathecal-related genes

et al. 2020

Self Cite

View full text Add to dashboard Cite

Background: Successful mating of female mosquitoes typically occurs once, with the male sperm being stored in the female spermatheca for every subsequent oviposition event. The female spermatheca is responsible for the maintenance, nourishment, and protection of the male sperm against damage during storage. Aedes aegypti is a major vector of arboviruses, including Yellow Fever, Dengue, Chikungunya, and Zika. Vector control is difficult due to this mosquito high reproductive capacity. Results: Following comparative RNA-seq analyses of spermathecae obtained from virgin and inseminated females, eight transcripts were selected based on their putative roles in sperm maintenance and survival, including energy metabolism, chitin components, transcriptional regulation, hormonal signaling, enzymatic activity, antimicrobial activity, and ionic homeostasis. In situ RNA hybridization confirmed tissue-specific expression of the eight transcripts. Following RNA interference (RNAi), observed outcomes varied between targeted transcripts, affecting mosquito survival, egg morphology, fecundity, and sperm motility within the spermathecae. Conclusions: This study identified spermatheca-specific transcripts associated with sperm storage in Ae. aegypti. Using RNAi we characterized the role of eight spermathecal transcripts on various aspects of female fecundity and offspring survival. RNAi-induced knockdown of transcript AeSigP-66,427, coding for a Na + /Ca 2+ protein exchanger, specifically interfered with egg production and reduced sperm motility. Our results bring new insights into the molecular basis of sperm storage and identify potential targets for Ae. aegypti control.

show abstract

Morphological and morphometrical assessment of spermathecae of Aedes aegypti females

Cited by 27 publications

References 37 publications

Dynamic Notch Signaling Specifies Each Cell Fate inDrosophilaSpermathecal Lineage

Dynamic Notch Signaling Specifies Each Cell Fate inDrosophilaSpermathecal Lineage

A mosquito sperm's journey from male ejaculate to egg: Mechanisms, molecules, and methods for exploration

Transcriptional profiling and physiological roles of Aedes aegypti spermathecal-related genes

Contact Info

Product

Resources

About