TARGET: a transient transformation system for genome-wide transcription factor target discovery.
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ABSTRACT:
SUBMITTER: Bargmann BO
PROVIDER: S-EPMC3660954 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:The transcription factor E2F4 is a member of the E2F family of regulators which has critical roles in cell cycle control and differentiation. In order to fully understand the physiological roles of E2F4 and the regulatory networks it mediates, and to reveal its relationships with other members of the E2F family, it is essential to comprehensively identify E2F4 target sites throughout the genome. Here, we investigated genome-wide E2F4 targets in human lymphoblastoid cells using the recently developed unbiased target discovery technique of ChIP sequencing. We sequecned E2F4 ChIP and corresponding Input
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Project description:Stage-specific transcription is a fundamental biological process in the life cycle of the Plasmodium parasite. Proteins containing the AP2 DNA-binding domain are responsible for stage-specific transcriptional regulation and belong to the only known family of transcription factors in Plasmodium parasites. Comprehensive identification of their target genes will advance our understanding of the molecular basis of stage-specific transcriptional regulation and stage-specific parasite development. AP2-O is an AP2 family transcription factor that is expressed in the mosquito midgut-invading stage, called the ookinete, and is essential for normal morphogenesis of this stage. In this study, we identified the genome-wide target genes of AP2-O by chromatin immunoprecipitation-sequencing and elucidate how this AP2 family transcription factor contributes to the formation of this motile stage. The analysis revealed that AP2-O binds specifically to the upstream genomic regions of more than 500 genes, suggesting that approximately 10% of the parasite genome is directly regulated by AP2-O. These genes are involved in distinct biological processes such as morphogenesis, locomotion, midgut penetration, protection against mosquito immunity and preparation for subsequent oocyst development. This direct and global regulation by AP2-O provides a model for gene regulation in Plasmodium parasites and may explain how these parasites manage to control their complex life cycle using a small number of sequence-specific AP2 transcription factors.
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