Isolation of Undifferentiated Female Germline Cells from Adult
            Drosophila
            Ovaries

Abstract The Drosophila melanogaster ovo gene is required for survival and differentiation of female germline cells, apparently playing a role in germline sex determination. We recovered 60 kb of genomic DNA from its genetic location at 4E1,2 on the X chromosome. A transcription unit coding for an apparently female-specific germline-dependent 5-kb poly(A)+ RNA size class is located substantially in a 7-kb region, within which three DNA-detectable lesions for mutations that inactivate the ovo function are located at two sites approximately 4 kb apart. The breakpoint of a deficiency that removes the neighboring lethal complementation group shavenbaby (svb) but leaves the ovo function intact maps approximately 5 kb to the molecular left of the leftmost ovo mutant site. A class of mutations that inactivates both the svb function and the ovo function affects genomic DNA between the two ovo sites. Sequences required for the two genetic functions are partly overlapping. In spite of this overlap, P element-mediated gene transfer of a 10-kb genomic DNA segment containing the 5-kb poly(A)+ RNA transcription unit rescues the female sterility phenotypes of ovo mutations, but not the svb lethality.

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Binding of SU(VAR)3-9 Partially Depends on SETDB1 in the Chromosomes of Drosophila melanogaster

Cells ◽

10.3390/cells8091030 ◽

2019 ◽

Vol 8 (9) ◽

pp. 1030 ◽

Cited By ~ 1

Author(s):

Daniil A. Maksimov ◽

Dmitry E. Koryakov

Keyword(s):

Developmental Stages ◽

Critical Role ◽

Single Copy ◽

Nurse Cells ◽

Wild Type ◽

Histone Methyltransferases ◽

Adult Females ◽

Germline Cells ◽

Differentiation Stage ◽

Female Germline

H3K9 methylation is known to play a critical role in gene silencing. This modification is established and maintained by several enzymes, but relationships between them are not fully understood. In the present study, we decipher the interplay between two Drosophila H3K9-specific histone methyltransferases, SU(VAR)3-9 and SETDB1. We asked whether SETDB1 is required for targeting of SU(VAR)3-9. Using DamID-seq, we obtained SU(VAR)3-9 binding profiles for the chromosomes from larval salivary glands and germline cells from adult females, and compared profiles between the wild type and SETDB1-mutant backgrounds. Our analyses indicate that the vast majority of single copy genes in euchromatin are targeted by SU(VAR)3-9 only in the presence of SETDB1, whereas SU(VAR)3-9 binding at repeated sequences in heterochromatin is largely SETDB1-independent. Interestingly, piRNA clusters 42AB and 38C in salivary gland chromosomes bind SU(VAR)3-9 regardless of SETDB1, whereas binding to the same regions in the germline cells is SETDB1-dependent. In addition, we compared SU(VAR)3-9 profiles in female germline cells at different developmental stages (germarium cells in juvenile ovaries and mature nurse cells). It turned out that SU(VAR)3-9 binding is influenced both by the presence of SETDB1, as well as by the differentiation stage.

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The Balbiani Body in the Female Germline Cells of an Earwig,Opisthocosmia silvestris

ZOOLOGICAL SCIENCE ◽

10.2108/zsj.26.754 ◽

2009 ◽

Vol 26 (11) ◽

pp. 754-757 ◽

Cited By ~ 12

Author(s):

Waclaw Tworzydlo ◽

Malgorzata Kloc ◽

Szczepan M. Bilinski

Keyword(s):

Balbiani Body ◽

Germline Cells ◽

Female Germline

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Oogenesis of Hematophagous Midge Forcipomyia taiwana (Diptera: Ceratopogonidae) and Nuage Localization of Vasa in Germline Cells

Insects ◽

10.3390/insects11020106 ◽

2020 ◽

Vol 11 (2) ◽

pp. 106

Author(s):

Wang ◽

Ching ◽

Krishnaraj ◽

Chen ◽

Radhakrishnan ◽

...

Keyword(s):

Electron Microscopy ◽

Nuclear Envelope ◽

Reproductive Biology ◽

Pest Control ◽

Nurse Cell ◽

Control Strategies ◽

Germline Cells ◽

High Degree ◽

Female Germline ◽

Transgenic Flies

Forcipomyia taiwana is an irritating hematophagous midge that preferentially attacks humans and affects leisure industries in Taiwan. Understanding the female reproductive biology of such pests would facilitate the development of pest control strategies. However, knowledge about oogenesis in the genus Forcipomyia is unavailable. Accordingly, we examined the ovariole structure and features of oogenesis in terms of the oocyte and the nurse cell. After being blood-fed, we observed a high degree of gonotrophic harmony—the synchronization of developing follicles. The follicle of the F. taiwana has only one nurse cell connected to the oocyte, which is distinct among hematophagous midges. In the nurse cell, we identified the perinuclear localization of the germline marker, Vasa. The Vasa localization is reminiscent of the nuclear envelope-associated nuage observed by electron microscopy. To determine whether F. taiwana Vasa (FtVasa) is an authentic nuage component, we produced transgenic flies expressing FtVasa in the female germline and proved that FtVasa was able to be localized to Drosophila nuage. By characterizing the oogenesis and Vasa expression in the germline cells of F. taiwana, this study extends knowledge about the female reproductive biology of hematophagous midges.

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Oogenesis in Crustaceans: Ultrastructural Aspects and Selected Regulating Factors

Reproductive Biology ◽

10.1093/oso/9780190688554.003.0002 ◽

2020 ◽

pp. 29-59

Author(s):

Mariusz K. Jaglarz ◽

Szczepan M. Bilinski

Keyword(s):

Great Majority ◽

Follicle Cells ◽

Nurse Cells ◽

Germline Development ◽

Cellular Processes ◽

Ultrastructural Studies ◽

Large Numbers ◽

Oocyte Cytoplasm ◽

Germline Cells ◽

Female Germline

This chapter explores ultrastructural aspects of crustacean oogenesis. It focuses on various cellular processes associated with female germline development in selected crustacean groups. Oogenesis in crustaceans comprises four stages: proliferation of germline cells, previtellogenesis, vitellogenesis, and formation of egg coverings. The greater part of oogenesis occurs in the ovary. In Crustacea, two structurally and functionally distinct types of ovary are recognized: panoistic and meroistic. In panoistic ovaries, all germline cells differentiate into oocytes, and this type of ovarian organization occurs in a great majority of crustaceans, including Malacostraca. In contrast, in the meroistic ovaries, oogonial cells are connected by intercellular bridges and form characteristic linear cysts. Within each cyst, only one cell becomes an oocyte, and the remaining cells differentiate into nurse cells. Meroistic ovaries are typical for Branchiopoda and Ostracoda: Podocopida. Ultrastructural studies reveal that the nucleus and cytoplasmic organelles of the oocyte are highly synthetically active in the panoistic ovary, whereas in the meroistic type, oocyte development is supported, to some extent, by accompanying nurse cells. During previtellogenesis, oocytes accumulate large numbers of various organelles, e.g. ribosomes, mitochondria, and cisternae of endoplasmic reticulum. The oocyte cytoplasm also contains characteristic disc-shaped bodies and cortical granules. A comparative analysis of the proteinaceous yolk formation in different crustaceans reveals two distinct types of vitellogenesis (autosynthesis and heterosynthesis), and indicates that a mixed type prevails in these arthropods. In most crustacean species, germline cells associate with somatic follicle cells that may fulfill several functions during oogenesis.

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