JP Maree
I am a postdoctoral researcher and lecturer at Villanova University (PA, USA) in the Department of Biology. My current research focuses on DNA compaction and epigenetic control in trypanosomatids, a group of medically important flagellated protists that are eukaryotic parasites. I obtained my PhD in Biochemistry, with a specific focus on epigenetics, at the University of Stellenbosch in 2020. My PhD research focused on the epigenome of Trypanosoma brucei, an early divergent eukaryote that causes African sleeping sickness in humans and Nagana in livestock. I obtained an MSc in Biochemistry from the University of the Free State, focussing on genomics, and graduated Cum Laude in 2014.
Training experience includes micro- and molecular biology, biochemistry, proteomics, genomics, epigenetics, and bioinformatics. I have hands-on experience in high-throughput sequencing technologies, mass spectrometric analysis, molecular biology, bioinformatics data analysis, tutoring and post-grad research supervision. In addition, I was the chair of the H3Africa Fellows Club and editor-in-chief of the H3Africa Newsletter, a co-funded initiative of the Wellcome Trust and NIH, distributing knowledge from primary research back to African communities.
Training experience includes micro- and molecular biology, biochemistry, proteomics, genomics, epigenetics, and bioinformatics. I have hands-on experience in high-throughput sequencing technologies, mass spectrometric analysis, molecular biology, bioinformatics data analysis, tutoring and post-grad research supervision. In addition, I was the chair of the H3Africa Fellows Club and editor-in-chief of the H3Africa Newsletter, a co-funded initiative of the Wellcome Trust and NIH, distributing knowledge from primary research back to African communities.
less
InterestsView All (13)
Uploads
Papers by JP Maree
coincided with significant evolutionary diversification. However, chromatin generally represses DNA function, and
mechanisms coevolved to regulate chromatin structure and its impact on DNA. This included the selection of specific
nucleosome positions to modulate accessibility to the DNA molecule. Trypanosoma brucei, a member of the Excavates
supergroup, falls in an ancient evolutionary branch of eukaryotes and provides valuable insight into the organization
of chromatin in early genomes.
Results: We have mapped nucleosome positions in T. brucei and identified important differences compared to other
eukaryotes: The RNA polymerase II initiation regions in T. brucei do not exhibit pronounced nucleosome depletion,
and show little evidence for defined −1 and +1 nucleosomes. In contrast, a well‑positioned nucleosome is present
directly on the splice acceptor sites within the polycistronic transcription units. The RNA polyadenylation sites were
depleted of nucleosomes, with a single well‑positioned nucleosome present immediately downstream of the pre‑
dicted sites. The regions flanking the silent variant surface glycoprotein (VSG) gene cassettes showed extensive arrays
of well‑positioned nucleosomes, which may repress cryptic transcription initiation. The silent VSG genes themselves
exhibited a less regular nucleosomal pattern in both bloodstream and procyclic form trypanosomes. The DNA replication origins, when present within silent VSG gene cassettes, displayed a defined nucleosomal organization compared
with replication origins in other chromosomal core regions.
Conclusions: Our results indicate that some organizational features of chromatin are evolutionarily ancient, and may
already have been present in the last eukaryotic common ancestor.
coincided with significant evolutionary diversification. However, chromatin generally represses DNA function, and
mechanisms coevolved to regulate chromatin structure and its impact on DNA. This included the selection of specific
nucleosome positions to modulate accessibility to the DNA molecule. Trypanosoma brucei, a member of the Excavates
supergroup, falls in an ancient evolutionary branch of eukaryotes and provides valuable insight into the organization
of chromatin in early genomes.
Results: We have mapped nucleosome positions in T. brucei and identified important differences compared to other
eukaryotes: The RNA polymerase II initiation regions in T. brucei do not exhibit pronounced nucleosome depletion,
and show little evidence for defined −1 and +1 nucleosomes. In contrast, a well‑positioned nucleosome is present
directly on the splice acceptor sites within the polycistronic transcription units. The RNA polyadenylation sites were
depleted of nucleosomes, with a single well‑positioned nucleosome present immediately downstream of the pre‑
dicted sites. The regions flanking the silent variant surface glycoprotein (VSG) gene cassettes showed extensive arrays
of well‑positioned nucleosomes, which may repress cryptic transcription initiation. The silent VSG genes themselves
exhibited a less regular nucleosomal pattern in both bloodstream and procyclic form trypanosomes. The DNA replication origins, when present within silent VSG gene cassettes, displayed a defined nucleosomal organization compared
with replication origins in other chromosomal core regions.
Conclusions: Our results indicate that some organizational features of chromatin are evolutionarily ancient, and may
already have been present in the last eukaryotic common ancestor.