Category Archives: News

Introducing Dr. Xiaolu Wei

Dr. Xiaolu Wei cutting her lovely cake.

Congratulations to Dr. Xiaolu Wei for successfully defending her thesis! Dr. Wei gave an awesome talk on meiotic drive and satellite DNA regulation in Drosophila melanogaster. We are so proud of her!

All of the science on that cake…

A couple years of progress and fun: 2021-2022 whirlwind

What a whirlwind the past couple of years has been!  Check out what we’ve been up to in 2021 and 2022:

  • The lab had a lot of fun at GLAM EvoGen in Buffalo this year.
    Emiliano, Xiaolu, and Cecile enjoying a post-GLAM meal.

    Undergraduate Miraz Sadi gives a great lightning talk on centromere evolution at GLAM Evogen in Buffalo, NY.
  • Matt Lindsay passed his quals. Congratulations Matt!

    Matt passed his quals and is now a PhD candidate!
  • Emiliano Martí joined the lab and will be co-advised by Daven Presgraves.

    Emiliano, an E2G2 grad student, joined the Larracuente and Presgraves labs
  • In 2022 we’ve been busy with papers on Y chromosomes, drivers, and telomeres, oh my!
  • We said goodbye to amazing undergraduates who are moving on to bigger and better things! Congratulations, Tuan, Sherif, Vera, Eddyson, and Chuqin.

    Tuan Pham (left) and Sherif Negm (right) are off to PhD programs Brown University and the University of Chicago, respectively. Congratulations graduates!
  • Our NIH MIRA grant was renewed. We are excited to continue our work on satellite DNA functional and evolutionary genomics!
  • Xiaolu’s paper on satellite regulation came out in eLife.
  • Check out this blog from the NSF on our hackathon: Hacking is a broader impact activity

Ching-Ho Chang receives the Sandler Award!

Ching-Ho Chang is the 2021 recipient of the prestigious Larry Sandler Award  (https://genestogenomes.org/ching-ho-chang-to-give-larry-sandler-memorial-lecture-at-dros21/). This award honors Dr. Larry Sandler for his many important contributions to Drosophila genetics, including his foundational work on meiotic drive.  The award is given to an outstanding recent doctoral graduate working on Drosophila genetics, based their thesis. Ching-Ho’s thesis focused on how genetic conflicts, and especially meiotic drive, shape chromosome evolution in Drosophila. As the award winner, Ching-Ho delivered the Larry Sandler Memorial Lecture at the 2021 annual Drosophila research conference. We are so proud of Ching-Ho!!

GIDS first biomedical data science hackathon

Congratulations to team supergene–Sherif Negm (team captain), Xiaolu Wei, John Sproul and Lucas Hemmer— for coming in 2nd place in the open division of the  GIDS biomedical data science hackathon! Way to represent the lab and the Bio Department.

Team supergene! Postdoc John Sproul (top left), undergraduate and team captain Sherif Negm (top right), grad student Xiaolu Wei (bottom left), and postdoc Lucas Hemmer (bottom right)

Congratulations Dr. Chang!

Ching-Ho successfully defended his dissertation on “Meiotic drive and rapid genome evolution in Drosophila”. He will start his postdoctoral work at the Fred Hutchison Cancer Research Center this April. We’ll miss you greatly Dr. Chang!

Photo credit: Tip Benyajati

Paper on Drosophila melanogaster centromeres is out!

Check out our new paper on the organization of Drosophila melanogaster centromeres. For this paper, our lab collaborated with Barbara Mellone’s lab (University of Connecticut) and Ting Wu’s lab (Harvard University) to discover all of the centromeres in D. melanogaster. Centromeres are genomic regions essential for proper chromosome segregation during cell division. They also are among the most rapidly evolving regions of genomes and can play a role in karyotype evolution and speciation. We know little about the detailed organization of centromeres because they are buried in large blocks of tandem repeats that are difficult to assemble. We combined Ching-Ho’s heterochromatin-enriched assembly methods, with ChIP-seq for the centromere-specific histone variant, CENP-A, and FISH on stretched chromatin fibers to reveal the DNA sequences underlying centromeres. It turns out that centromeres correspond to islands rich in retroelements embedded in a sea of satellite DNA! One retroelement, G2/Jockey-3, is found at all D. melanogaster centromeres and centromeres in D. simulans.

Retroelements are associated with centromeres in a wide range of organisms including fungi, plants, and mammals. This suggests that retroelements may be conserved features of centromeres and may have a role in centromere function. We’re currently working on studying patterns of polymorphism and divergence in G2/Jockey-3 and centromere islands to see how they contribute to centromere evolution and function.

Drosophila centromere organization and widespread presence of retroelements at centromeres.
Figure 7 from the centromere paper. (A) Schematic showing the organization of D. melanogaster centromeres. (B) Phylogenetic tree showing that centromere-associated retroelements are common across highly diverged lineages: Gossypium hirsutum (cotton), Zea mays mays (maize), Oryza sativa (rice), Triticum boeoticum (wild wheat), Cryptococcus, Phyllostomid (bat), Hoolock leuconedys (gibbon), Homo sapiens (human) (and a human neocentromere), Macropus eugenii (tammar wallaby), Phascolarctos cinereus (koala), and D. melanogaster (this study for endogenous centromeres; also in an X-derived minichromosome).

Taylar graduates with honors in research

Taylar successfully defended her senior thesis on suppressors of Segregation Distorter in Drosophila melanogaster and is graduating with honors in research this weekend! Next up for Taylar is the Cell, Development, Molecular Biology and Biophysics PhD program Johns Hopkins, where she will be a Morgan Fellow. Congratulations all around Taylar!