| 1. |
- Richards, Stephen, et al.
(författare)
-
The genome of the model beetle and pest Tribolium castaneum.
- 2008
-
Ingår i: Nature. - 1476-4687. ; 452:7190, s. 949-55
-
Tidskriftsartikel (refereegranskat)abstract
- Tribolium castaneum is a representative of earth’s most numerous eukaryotic order, a powerful model organism for the study of generalized insect development, and also an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved an ability to interact with a diverse chemical environment as evidenced by large expansions in odorant and gustatory receptors, as well as p450 and other detoxification enzymes. Developmental patterns in Tribolium are more representative of other arthropods than those found in Drosophila, a fact represented in gene content and function. For one, Tribolium has retained more ancestral genes involved in cell-cell communication than Drosophila, and some are expressed in the growth zone crucial for axial elongation in short germ development. Systemic RNAi in T. castaneum appears to use mechanisms distinct from those found in C. elegans, but nevertheless offers similar power for the elucidation of gene function and identification of targets for selective insect control.
|
|
| 2. |
- Werren, John H, et al.
(författare)
-
Functional and evolutionary insights from the genomes of three parasitoid Nasonia species.
- 2010
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 327:5963, s. 343-8
-
Tidskriftsartikel (refereegranskat)abstract
- We report here genome sequences and comparative analyses of three closely related parasitoid wasps: Nasonia vitripennis, N. giraulti, and N. longicornis. Parasitoids are important regulators of arthropod populations, including major agricultural pests and disease vectors, and Nasonia is an emerging genetic model, particularly for evolutionary and developmental genetics. Key findings include the identification of a functional DNA methylation tool kit; hymenopteran-specific genes including diverse venoms; lateral gene transfers among Pox viruses, Wolbachia, and Nasonia; and the rapid evolution of genes involved in nuclear-mitochondrial interactions that are implicated in speciation. Newly developed genome resources advance Nasonia for genetic research, accelerate mapping and cloning of quantitative trait loci, and will ultimately provide tools and knowledge for further increasing the utility of parasitoids as pest insect-control agents.
|
|
| 3. |
- Anderl, Ines, 1973-
(författare)
-
Activation of the Cellular Immune Response in Drosophila melanogaster Larvae
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- During the last 40 years, Drosophila melanogaster has become an invaluable tool in understanding innate immunity. The innate immune system of Drosophila consists of a humoral and a cellular component. While many details are known about the humoral immune system, our knowledge about the cellular immune system is comparatively small. Blood cells or hemocytes constitute the cellular immune system. Three blood types have been described for Drosophila larvae. Plasmatocytes are phagocytes with a plethora of functions. Crystal cells mediate melanization and contribute to wound healing. Plasmatocytes and crystal cells constitute the blood cell repertoire of a healthy larva, whereas lamellocytes are induced in a demand-adapted manner after infection with parasitoid wasp eggs. They are involved in the melanotic encapsulation response against parasites and form melanotic nodules that are also referred to as tumors.In my thesis, I focused on unraveling the mechanisms of how the immune system orchestrates the cellular immune response. In particular, I was interested in the hematopoiesis of lamellocytes.In Article I, we were able to show that ectopic expression of key components of a number of signaling pathways in blood cells induced the development of lamellocytes, led to a proliferative response of plasmatocytes, or to a combination of lamellocyte activation and plasmatocyte proliferation.In Article II, I combined newly developed fluorescent enhancer-reporter constructs specific for plasmatocytes and lamellocytes and developed a “dual reporter system” that was used in live microscopy of fly larvae. In addition, we established flow cytometry as a tool to count total blood cell numbers and to distinguish between different blood cell types. The “dual reporter system” enabled us to differentiate between six blood cell types and established proliferation as a central feature of the cellular immune response. The combination flow cytometry and live imaging increased our understanding of the tempo-spatial events leading to the cellular immune reaction.In Article III, I developed a genetic modifier screen to find genes involved in the hematopoiesis of lamellocytes. I took advantage of the gain-of-function phenotype of the Tl10b mutation characterized by an activated cellular immune system, which induced the formation blood cell tumors. We screened the right arm of chromosome 3 for enhancers and suppressors of this mutation and uncovered ird1.Finally in Article IV, we showed that the activity of the Toll signaling pathway in the fat body, the homolog of the liver, is necessary to activate the cellular immune system and induce lamellocyte hematopoiesis.
|
|
| 4. |
- Anderl, Ines, et al.
(författare)
-
New ways to make a blood cell
- 2015
-
Ingår i: eLIFE. - 2050-084X. ; 4
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 5. |
- Anderl, Ines, et al.
(författare)
-
Transdifferentiation and Proliferation in Two Distinct Hemocyte Lineages in Drosophila melanogaster Larvae after Wasp Infection
- 2016
-
Ingår i: PLoS Pathogens. - : Public library science. - 1553-7366 .- 1553-7374. ; 12:7
-
Tidskriftsartikel (refereegranskat)abstract
- Cellular immune responses require the generation and recruitment of diverse blood cell types that recognize and kill pathogens. In Drosophila melanogaster larvae, immune-inducible lamellocytes participate in recognizing and killing parasitoid wasp eggs. However, the sequence of events required for lamellocyte generation remains controversial. To study the cellular immune system, we developed a flow cytometry approach using in vivo reporters for lamellocytes as well as for plasmatocytes, the main hemocyte type in healthy larvae. We found that two different blood cell lineages, the plasmatocyte and lamellocyte lineages, contribute to the generation of lamellocytes in a demand-adapted hematopoietic process. Plasmatocytes transdifferentiate into lamellocyte-like cells in situ directly on the wasp egg. In parallel, a novel population of infection-induced cells, which we named lamelloblasts, appears in the circulation. Lamelloblasts proliferate vigorously and develop into the major class of circulating lamellocytes. Our data indicate that lamellocyte differentiation upon wasp parasitism is a plastic and dynamic process. Flow cytometry with in vivo hemocyte reporters can be used to study this phenomenon in detail.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Cinege, Gyöngyi, et al.
(författare)
-
Broad Ultrastructural and Transcriptomic Changes Underlie the Multinucleated Giant Hemocyte Mediated Innate Immune Response against Parasitoids
- 2022
-
Ingår i: Journal of Innate Immunity. - : S. Karger. - 1662-811X .- 1662-8128. ; 14:4, s. 335-354
-
Tidskriftsartikel (refereegranskat)abstract
- Multinucleated giant hemocytes (MGHs) represent a novel type of blood cell in insects that participate in a highly efficient immune response against parasitoid wasps involving isolation and killing of the parasite. Previously, we showed that circulating MGHs have high motility and the interaction with the parasitoid rapidly triggers encapsulation. However, structural and molecular mechanisms behind these processes remained elusive. Here, we used detailed ultrastructural analysis and live cell imaging of MGHs to study encapsulation in Drosophila ananassae after parasitoid wasp infection. We found dynamic structural changes, mainly driven by the formation of diverse vesicular systems and newly developed complex intracytoplasmic membrane structures, and abundant generation of giant cell exosomes in MGHs. In addition, we used RNA sequencing to study the transcriptomic profile of MGHs and activated plasmatocytes 72 h after infection, as well as the uninduced blood cells. This revealed that differentiation of MGHs was accompanied by broad changes in gene expression. Consistent with the observed structural changes, transcripts related to vesicular function, cytoskeletal organization, and adhesion were enriched in MGHs. In addition, several orphan genes encoding for hemolysin-like proteins, pore-forming toxins of prokaryotic origin, were expressed at high level, which may be important for parasitoid elimination. Our results reveal coordinated molecular and structural changes in the course of MGH differentiation and parasitoid encapsulation, providing a mechanistic model for a powerful innate immune response.
|
|
| 10. |
- Cinege, Gyöngyi, et al.
(författare)
-
Cellular immunity of Drosophila willistoni reveals novel complexity in insect anti-parasitoid defense
- 2024
-
Ingår i: Cells. - : MDPI. - 2073-4409. ; 13:7
-
Tidskriftsartikel (refereegranskat)abstract
- Coevolution of hosts and their parasites has shaped heterogeneity of effector hemocyte types, providing immune defense reactions with variable effectiveness. In this work, we characterize hemocytes of Drosophila willistoni, a species that has evolved a cellular immune system with extensive variation and a high degree of plasticity. Monoclonal antibodies were raised and used in indirect immunofluorescence experiments to characterize hemocyte subpopulations, follow their functional features and differentiation. Pagocytosis and parasitization assays were used to determine the functional characteristics of hemocyte types. Samples were visualized using confocal and epifluorescence microscopy. We identified a new multinucleated giant hemocyte (MGH) type, which differentiates in the course of the cellular immune response to parasitoids. These cells differentiate in the circulation through nuclear division and cell fusion, and can also be derived from the central hematopoietic organ, the lymph gland. They have a binary function as they take up bacteria by phagocytosis and are involved in the encapsulation and elimination of the parasitoid. Here, we show that, in response to large foreign particles, such as parasitoids, MGHs differentiate, have a binary function and contribute to a highly effective cellular immune response, similar to the foreign body giant cells of vertebrates.
|
|
