Jumana AlHaj Abed newest Group Leader
A new lab to unravel the mystery of chromosome pairing
The Max Planck Institute of Immunobiology and Epigenetics is pleased to announce the appointment of Dr Jumana AlHaj Abed as the newest Group Leader. The AlHaj Abed lab is exploring the complex world of how our inherited genetic material interacts within our cells, which has profound implications for understanding gene regulation, development, and disease. The research focuses on the interplay between epigenetic programs and parental genome packaging in the nucleus, with a particular interest in understanding the extent to which gene regulation is coordinated between maternal and paternal chromosomes.
In every cell’s nucleus, chromosomes exist not as isolated entities but as interactive structures. How chromosomes are organized and folded affects how genes are regulated and control various processes in our bodies. This is crucial in species ranging from fruit flies to humans.
The newly established AlHaj Abed laboratory at the MPI-IE wants to explore these non-random patterns of chromosome organization and gene regulation. Through advanced techniques such as super-resolution imaging and whole genome chromatin conformation capture, the team investigates genome organization principles, homolog folding at different scales, and the impact of irregular chromosome folding.
Unique Contributions of Maternal and Paternal Chromosomes
“One of our main interests is to understand how the chromosomes we inherit from our mothers and fathers interact and communicate within our cells. Although we have some understanding of mechanisms governing gene regulation within a single chromosome, less is known about the mechanisms governing interactions between maternal and paternal chromosomes,” says Jumana AlHaj Abed. This gap in understanding largely stems from the challenge of differentiating between the two sets of chromosomes, given their nearly identical sequences. “By employing allele-specific genomic methods and leveraging the latest advancements in imaging technology, we overcame this longstanding challenge of distinguishing the contributions of each parent’s chromosomes. And now we aim to unravel the intricacies of how gene regulation occurs between maternal and paternal chromosomes, particularly within the context of the cell’s nuclear environment.”
Homologous chromosome interactions, are crucial for genome function in fruit flies and mammals. In Drosophila, chromosomes from each parent pair up continuously and in a very structured way, which influences the gene activity. In mammals, including humans, this pairing is less common and happens only temporarily, but it is still critical for key processes like DNA repair, cell development, and how certain genes are turned on or off.
Chromosome Pairing and Gene Regulation
The team wants to understand how these paired chromosome are folded and contribute to gene regulation across different tissues. In Drosophila, research indicates that these interactions are complex, involving loops and domains, and affect gene expression differently based on the homologous chromosome alignment. Recent studies in mammals show increasing evidence supporting somatic homolog pairing, similar to Drosophila.
However, the research of the AlHaj Abed lab is not just curiosity-driven – it has significant implications for understanding human development and some disease mechanisms.
“We are thrilled to welcome Jumana to our institute. Her expertise in the somatic pairing of homologous chromosomes aligns seamlessly with the institute’s research program,” says Managing Director Ibrahim Cissé. “Jumana’s dedication exploring the intricacies of the chromosomal organization is a perfect fit for us. We eagerly anticipate the valuable insights she will bring to the Max Planck Institute’s ongoing efforts to advance knowledge in this field of epigenetics. Her recruitment really expands our commitment to make Freiburg a hub of exciting Biophysics research.”
Jumana AlHaj Abed officially joined the Max Planck Institute of Immunobiology and Epigenetics in Freiburg in December 2023. Her lab has open positions available for Postdocs and lab technicians.
Could you describe your current field of work and how your research focus has evolved over the past few years?
Starting with my PhD, my career path began with a keen interest in understanding how epigenetic programs initiate de novo within development. Then, during my postdoc, with a real appreciation for imaging and sequencing technological advancements I developed and harnessed new techniques that allowed me to distinguish maternal and paternal sequences to answer questions at the global genomic scale. Coming full circle, my lab will use these cool technologies, to understand epigenetic programs within development and their relationship to parental genome interactions.
The research in my lab will focus on distinguishing meaningful chromosome interactions at the gene level between paternal and maternal chromosomes and how those interplay with epigenetic marks within the cells in tissue-specific contexts. In addition, we aim to understand the step-by-step process by which maternal and paternal chromosomes communicate, when they do, and which factors facilitate this communication.
During your postdoctoral tenure in the Wu lab, you specialized in chromatin confirmation capture combined with Next Generation Sequencing (NGS) (Hi-C) and super-resolution imaging techniques. How can they help you advancing your research objectives?
They are powerful and complementary tools, where Hi-C provides a global genomic view at the cell population level, and super-resolution imaging with OligoSTORM gives a 3-dimensional super-resolved (10s of nm) view of the genome at the single cell level. The ultimate goal would be to combine the strength of both techniques and try to see whole genome communication and its consequences at super-resolution.
Beyond the pure biological curiosity and contributing to knowledge in your field, in what practical ways could your research findings be applied?
Although the questions seem curiosity driven, they are actually aimed at addressing how basic principles of communication between homologous chromosomes are established. When we understand these principles from the ground up, we can better assess problems that arise as a result of “miscommunication” between homologous chromosomes. This includes improper folding of chromatin in cancer, and the presence of additional chromosomal copies such as in chromosome trisomies.
You show an image on your website featuring the silhouette of a woman. Who is this and what does this image mean to you? Could you share your personal interpretation or connection to this image?
This is Nettie Steven’s silhouette. She discovered the sex chromosomes and detected homologous chromosome pairing during different cell cycle stages in Drosophila using a light microscope around 1908 – more than a hundred years ago! Since then, in 1954, Ed Lewis contributed to the understanding that homologous chromosome pairing rescues different mutations when the mutations are complementary to each other (i.e., trans-allelic complementation events). He found this by setting up genetic crosses between fruit flies and tracking specific traits. However, why the phenomenon of chromosome pairing is so widespread in Drosophila is still unknown!
I should also add Ed Lewis’ picture there because they both contributed to our understanding to chromosome structure in profound ways before the field of genome structure and function even existed. I am amazed by their ability to come at really cool discoveries even before the advancement of molecular biology techniques, and I hope to address age-old questions with the same rigor because clearly, there is so much that we still do not know.
What was the driving force or inspiration behind your decision to pursue a career in science?
I love to understand how things work and what goes wrong when they do not work, from a small molecular scale to organism-level big picture. How are our cells and DNA such well-tuned machines? In addition, working with colleagues in science is such a perk because we are all trying to solve the same mysteries in creative ways.
What is the most valuable piece of advice related to science that you have received, and how has it influenced your career?
Ideas are a dime a dozen, and anyone can have a good idea, but if you are true to your perspective and the kind of scientist you are, it makes all the difference in the kind of science you can contribute.
To conclude, could you share a unique or surprising aspect about yourself that people wouldn't know by looking at your CV?
I love literature and engineering and would have loved to pursue a degree in either specialty for my bachelors. Luckily, being a group leader allows me to engineer many experiments and hopefully tell many scientific stories about my findings.
CV Jumana AlHaj Abed
Dr Jumana AlHaj Abed was born in Jordan. She received her Bachelor’s degree in Genetics and Biotechnology from the Jordan University of Science and Technology in 2007. Jumana came to the USA as a Fulbright scholar and completed her PhD in Molecular and Cellular Biology at Southern Methodist University (Dallas, TX) and then joined Mitzi Kuroda’s laboratory at Harvard Medical School (Boston, MA) as a postdoctoral fellow. She later joined the laboratory of Chao-Ting Wu (Boston, MA) as a postdoctoral fellow and focused her research on the somatic pairing of homologous chromosomes. During that time, her research with colleagues has shown that pairing is a highly structured process (domains, loops, and compartments) with significant functional genome-wide consequences. Jumana is interested in these consequences and their relationship to epigenetic marks. She relies on the fly model system and mammalian cells to understand the differences in parental chromosome interactions across species and utilizes super-resolution microscopy together with Hi-C. Jumana Al-Haj Abed joined the Max Planck Institute of Immunobiology and Epigenetics in Freiburg as an Independent Group leader in December 2023.