Project description:In order to compare sexual and asexual multiplication in Malus domestica we performed mircoarray to study change in gene expression level in our sample.
Project description:In order to compare sexual and asexual multiplication in Malus domestica we performed bisulfite sequencing to study change in differentially methylated region
Project description:In the parasitic wasp Venturia canescens sexual and asexual populations coexist in sympatry and showed distinct foraging behaviours. By sequencing head transcriptome from sexual and asexual population, we assess transcriptomic divergence between the 2 populations.
Project description:Gibel carp (Carassius gibelio) is a cyprinid fish that originated in eastern Eurasia and is considered as invasive in European freshwater ecosystems. The populations of gibel carp in Europe are mostly composed of asexually reproducing triploid females (i.e., reproducing by gynogenesis) and sexually reproducing diploid females and males. Although some cases of coexisting sexual and asexual reproductive forms are known in vertebrates, the molecular mechanisms maintaining such coexistence are still in question. Both reproduction modes are supposed to exhibit evolutionary and ecological advantages and disadvantages. To better understand the coexistence of these two reproduction strategies, we performed transcriptome profile analysis of gonad tissues (ovaries), and studied the differentially expressed reproduction-associated genes in sexual and asexual females. We used high-throughput RNA sequencing to generate transcriptomic profiles of gonadal tissues of triploid asexual females and males, diploid sexual males and females of gibel carp, as well as diploid individuals from two closely-related species, C. auratus and Cyprinus carpio. Using SNP clustering, we showed the close similarity of C. gibelio and C. auratus with a basal position of C. carpio to both Carassius species. Using transcriptome profile analyses, we showed that many genes and pathways are involved in both gynogenetic and sexual reproduction in C. gibelio; however, we also found that 1500 genes, including 100 genes involved in cell cycle control, meiosis, oogenesis, embryogenesis, fertilization, steroid hormone signaling and biosynthesis were differently expressed in the ovaries of asexual and sexual females. We suggest that the overall downregulation of reproduction-associated pathways in asexual females, and their maintenance in sexual ones, allow for their stable coexistence, integrating the evolutionary and ecological advantages and disadvantages of the two reproductive forms. However, we showed that many sexual-reproduction-related genes are maintained and expressed in asexual females, suggesting that gynogenetic gibel carp retains the genetic toolkits for meiosis and sexual reproduction. These findings shed new light on the evolution of this asexual and sexual complex.
Project description:Aspergillus fumigatus is a thermotolerant saprobe found in soils and plant debris worldwide and an important pathogen of humans causing two million deaths annually. A. fumigatus makes abundant asexual spores (conidia) which are widely distributed by wind and can be inhaled from the environment. In susceptible individuals inhaled conidia break dormancy, germinate and grow in the lung leading to serious disease. Recent work has shown that conidia made at 37°C and 50°C have different morphologies and germination kinetics. While the asexual cycle is well-characterized at 37°C, much less is known about the asexual cycle at 50°C. Here, we combine flow cytometry and transcriptomics to track morphology and gene expression in the hyphae, conidiophores and conidia of A. fumigatus during asexual development at 37°C or 50°C. We show that the temperature during a narrow time window in late-stage conidiophore development dictates resulting conidial morphology, transcriptional program, and germination kinetics. As expected, conidiation at 37°C resulted in upregulation of brlA, the master regulator of asexual development, and its downstream targets in conidiophores and conidia. Surprisingly, conidiation at 50°C resulted in upregulation of MAT1-1, the master regulator of sexual development and its downstream targets in conidiophores and conidia. Our findings suggest that temperature during late conidiophore development transcriptionally primes conidia for asexual, parasexual or sexual development enhancing chances of survival for progeny. Our findings are especially relevant for agricultural compost where a wide gradient of temperatures exists, abundant A. fumigatus has been isolated, and resistance to antifungals is thought to evolve.
Project description:We demonstrate that Protein Phosphatase PfPPM2 regulates both asexual and sexual development of human malaria parasite P. falciparum. It is involved in the division of the parasite during asexual development and promotes its sexual differentiation. Phosphoproteomics studies revealed that PfPPM2 targets in the parasite include key regulators of protein translation and chromatin remodelling. We demonstrate that it regulates dephosphorylation of S33 of Heterochromatin Protein 1 (HP1), a regulator of heritable gene silencing and contributes to both mitotic proliferation as well as sexual differentiation of the parasite into sexual forms. Detailed investigations revealed that PfPPM2 mediated dephosphorylation of HP1 at S33 is a signal for parasite sexual conversion. HP1- S33 dephosphorylation impairs its interaction with trimethylated form of histone 3 (H3) at lysine 9 (H3K9me3), which is known to stabilize the heterochromatin. As a result, the expression of transcription of ap2g-which is repressed by HP1-H3K9me3-was stimulated resulting in sexual conversion of the parasite. Interestingly, the state of HP1-S33 phosphorylation seems to largely reflect the fate of the parasite-its optimal phosphorylation is important for asexual division whereas it is dephosphorylated form favours sexual differentiation. PfPPM2 also regulates protein synthesis in the parasite by repressing a signaling pathway involved in the phosphorylation of initiation factor eIF2α, which are likely to contribute to parasite division and possibly differentiation.