ABSTRACT: Global expression profiling reveals shared and distinct transcript signatures in arrested act2(-) and CDPK4(-) Plasmodium berghei gametocytes
Project description:Transcriptional profiling of gametocyte non-producer lines in Plasmodium berghei Transcriptome of gametocyte non producer lines (natural and genetic KO) and parental (820) lines. The aim of the study was to identify key genes involved in the decision to commit to gametocytogenesis in Plasmodium berghei. These microarrays compare naturally selected lines that do not produce gametocytes, and the parental line and additionally a genetic knock out of AP2-G PBANKA_143750. Data published Sinha, Hughes, et, al Nature tbc.
Project description:Transcriptional profiling of gametocyte non-producer lines in Plasmodium berghei Transcriptome of gametocyte non producer lines (natural and genetic KO) and parental (820) lines. The aim of the study was to identify key genes involved in the decision to commit to gametocytogenesis in Plasmodium berghei. These microarrays compare naturally selected lines that do not produce gametocytes, and the parental line and additionally a genetic knock out of AP2-G PBANKA_143750. Data published Sinha, Hughes, et, al Nature tbc. 2- colour microarray comparing to common background pool (containing all life cycle stages). Replicates of different life cycle stages of gametocyte non-producer lines and wild tye (WT) parental control lines
Project description:Gametocytogenesis and gametogenesis in malaria parasites are complex processes of cell differentiation and development likely involving many gene products. Gametocytes develop in the blood of the vertebrate host but mature gametocytes are not activated until taken up by the mosquito vector. Several distinct mutants have been described that block gametogenesis but the detailed molecular causes for the mutant phenotypes are not understood. To investigate whether a block in gametogenesis also results in a changed transcriptional profile, we studied two gene deletions mutants; act2(-) lacking stage-specific actin II and CDPK4(-) lacking calcium-dependent protein kinase 4. Whole-genome microarray analysis was performed from RNA of mature gametocytes to compare the transcriptomes of the mutants with wild-type Plasmodium berghei. The microarray analysis identified ~12% of all genes being differentially expressed in either or both mutants compared to normal gametocytes, as defined by at least two-fold change in transcript abundance. A large proportion of differentially expressed genes in both mutants overlapped consistent with the developmental gametocyte arrest. Distinct profiles in each mutant were also observed. Microarray experiments were performed as dual-color hybridizations on Agilent-024169 custom whole genome Plasmodium berghei 44K arrays. To compensate for dye-specific effects, a dye-reversal color-swap was applied.
Project description:During the malaria infection, Plasmodium parasites invade the host’s red blood cells where they can differentiate into two different life forms. The majority will replicate asexually and infect new erythrocytes. A small percentage, however, will transform into gametocytes – a specialized sexual stage able to survive and develop when taken up by Anopheles mosquito. As the gametocytes ensure the parasite’s transmission to a new host, their generation is an attractive target for new antimalarial interventions. The molecular mechanisms controlling gametocytogenesis, however, remain largely unknown due to the technical challenges: the early gametocytes are morphologically indistinguishable from asexual parasites and present in very low numbers during the infection. Recently, AP2-G - a transcription factor from an apicomplexa-specific apiAP2 family – was described as indispensable for gametocyte commitment in both human malaria parasite Plasmodium falciparum and rodent malaria model Plasmodium berghei. Therefore, we have decided to test whether the overexpression of this factor alone could increase gametocyte production and enable the investigation of uncharacterised, earliest stages of gametocyte development. To this end, we have engineered PBGAMi - a Plasmodium berghei line, in which all parasites were ap2-g deficient by default but able to overexpress it when induced with rapamycin. While the control parasites (PBGAMi R-), as expected, differentiated into asexual forms (schizonts) only, almost all rapamycin-treated parasites (PBGAMi R+) transformed into gametocytes. We used the generated line to perform RNA-seq analysis of the R- and R+ populations at different time points of their development and identify the changes arising between them, mapping the sequence of events leading to the formation of gametocytes. At the same time we have generated purified transcriptomes of male and female gametocytes for the reference
Project description:During the malaria infection, Plasmodium parasites invade the host’s red blood cells where they can differentiate into two different life forms. The majority will replicate asexually and infect new erythrocytes. A small percentage, however, will transform into gametocytes – a specialized sexual stage able to survive and develop when taken up by Anopheles mosquito. As the gametocytes ensure the parasite’s transmission to a new host, their generation is an attractive target for new antimalarial interventions. The molecular mechanisms controlling gametocytogenesis, however, remain largely unknown due to the technical challenges: the early gametocytes are morphologically indistinguishable from asexual parasites and present in very low numbers during the infection. Recently, AP2-G - a transcription factor from an apicomplexa-specific apiAP2 family – was described as indispensable for gametocyte commitment in both human malaria parasite Plasmodium falciparum and rodent malaria model Plasmodium berghei. Therefore, we have decided to test whether the overexpression of this factor alone could increase gametocyte production and enable the investigation of uncharacterised, earliest stages of gametocyte development. To this end, we have engineered PBGAMi - a Plasmodium berghei line, in which all parasites were ap2-g deficient by default but able to overexpress it when induced with rapamycin. While the control parasites (PBGAMi R-), as expected, differentiated into asexual forms (schizonts) only, almost all rapamycin-treated parasites (PBGAMi R+) transformed into gametocytes. We used the generated line to perform RNA-seq analysis of the R- and R+ populations at different time points of their development and identify the changes arising between them, mapping the sequence of events leading to the formation of gametocytes.
Project description:Gametocytogenesis and gametogenesis in malaria parasites are complex processes of cell differentiation and development likely involving many gene products. Gametocytes develop in the blood of the vertebrate host but mature gametocytes are not activated until taken up by the mosquito vector. Several distinct mutants have been described that block gametogenesis but the detailed molecular causes for the mutant phenotypes are not understood. To investigate whether a block in gametogenesis also results in a changed transcriptional profile, we studied two gene deletions mutants; act2(-) lacking stage-specific actin II and CDPK4(-) lacking calcium-dependent protein kinase 4. Whole-genome microarray analysis was performed from RNA of mature gametocytes to compare the transcriptomes of the mutants with wild-type Plasmodium berghei. The microarray analysis identified ~12% of all genes being differentially expressed in either or both mutants compared to normal gametocytes, as defined by at least two-fold change in transcript abundance. A large proportion of differentially expressed genes in both mutants overlapped consistent with the developmental gametocyte arrest. Distinct profiles in each mutant were also observed.
Project description:mRNA Transcripts expression profile of Plasmodium berghei infected host HepG2 cells with and without SUMO1 over expression. To check the changes in the transcript profiles upon SUMO1 over expression which is responsible for Plasmodium berghei parasite's growth arrest in host HepG2 cells.