Research in the Department of Cell Biology is focused on understanding molecular mechanisms of gene regulation in eukaryotic cells. Using mammalian cells, yeast, viruses, fruit flies and transgenic mice, we are investigating mechanisms of DNA replication and repair, control of the cell cycle and apoptosis, roles for transcriptional regulation and chromatin structure in gene expression, RNA processing, intracellular trafficking, membrane fusion and budding, mechanisms of generating antibody diversity, and the functions of cell surface sugars.
In the News
The Department of Cell Biology would like to extend a very warm welcome to our newest faculty member, Assistant Professor Dr. Kira Gritsman. Dr. Gritsman got her MD/PhD at New York University School of Medicine, where she performed her PhD research in Dr. Alexander Schier’s lab on the roles of nodal signaling during zebrafish gastrulation and left-right patterning. After an Internal Medicine residency at Columbia University Medical Center, she completed her subspecialty training in Hematology and Oncology at Dana-Farber Cancer Institute in Boston. She did her postdoctoral research in the labs of Dr. Gary Gilliland and Dr. Thomas Roberts at Dana-Farber on the roles of the PI3K/Akt pathway in hematopoiesis and leukemia. She is a recipient of an American Society of Hematology Fellow Scholar Award and a K08 Career Development award from the National Cancer Institute. Her lab's current work continues to focus on signaling pathways in hematopoietic stem cells and leukemic stem cells, and on resistance mechanisms to kinase inhibitors in leukemia.
Dr. Ulrich Steidl has received a prestigious Scholar Award from the Leukemia & Lymphoma Society for his work on the role of transcription and epigenetic regulation of hematopoietic and leukemic stem cells. A number of findings made by his research team also have implications for treating blood cancers including myeloid leukemias and myelodysplastic syndromes. Congratulations!
Dr. Pamela Stanley was awarded with the eighth annual Marshall S. Horwitz, M.D. Faculty Prize for Research Excellence. The prize will be awarded at a community-wide ceremony on Monday, February 3, 2014, during which Dr. Stanley will deliver a lecture, “Glycans that Regulate Development and Notch Signaling,” describing the work that led to her selection. Congratulations to Dr. Pamela Stanley.
Dr. Britta Will, a postdoctoral research fellow in the lab of Dr. Ulrich Steidl, was awarded with the 2013 annual Dennis Shields Postdocoral Research Prizes. Congratulations to Dr. Britta Will and the lab of Dr. Ulrich Steidl.
From the Skoultchi and Fyodorov Labs - Kavi H, Lu X, Xu N, Bartholdy BA, Vershilova E, Skoultchi AI, Fyodorov DV.A Genetic Screen and Transcript Profiling Reveal a Shared Regulatory Program for Drosophila Linker Histone H1 and Chromatin Remodeler CHD1. G3 (Bethesda). 2015 Jan 27. pii: g3.115.016709. doi: 10.1534/g3.115.016709.
• This study describes a genetic screen that identifies 61 enhancers and suppressors of the Drosophila histone H1 gene His1, including a mis-expression allele of Chd1 that encodes a chromatin remodeling enzyme CHD1.
From the Scharff Lab - Lirong Wei, Richard Chahwan, Shanzhi Wang, Xiaohua Wang, Phuong T. Pham, Myron F. Goodman, Aviv Bergman, Matthew D. Scharff and Thomas MacCarthy. Overlapping hotspots in CDRs are critical sites for V region diversification. Proc Natl Acad Sci U S A. 2015 Feb 2. pii: 201500788. [Epub ahead of print]. PMID: 25646473
• Overlapping hotspot motifs allow AID to focus the hypermutation of antibody genes on sites required to create high affinity broadly cross neutralizing antibodies.
From the Scharff Lab - Xiaohua Wang, Manxia Fan, Susan Kalis, Lirong Wei and Matthew D. Scharff. A source of the single-stranded DNA substrate for activation-induced deaminase during somatic hypermutation. Nat Commun. 2014 Jun 13;5:4137. doi: 10.1038/ncomms5137. PMID: 24923561
• The somatic mutation of immunoglobulin genes is associated with pausing of transcription, prolongation of initiation and perhaps an increase in prematuration termination regulated by Spt5.
From the Fyodorov and Keogh labs - Alexander V. Emelyanov, Joshua Rabbani, Monika Mehta, Elena Vershilova, Michael C. Keogh and Dmitry V. Fyodorov. Drosophila TAP/p32 is a core histone chaperone that cooperates with NAP-1, NLP, and nucleophosmin in sperm chromatin remodeling during fertilization. Genes & Development 28: 2027-2040.
• This work identifies in vitro and in vivo four Drosophila histone chaperones (NAP-1, NLP, Nph and TAP/p32) as the major factors of protamine eviction that convert protamine-based sperm chromatin into nucleosome-based somatic cell chromatin during fertilization.
From the Schildkraut Lab - Jeannine Gerhardt, Nikica Zaninovic, Qiansheng Zhan, Advaitha Madireddy, Sarah L. Nolin, Nicole Ersalesi, Zi Yan, Zev Rosenwaks and Carl L. Schildkraut. Cis-acting DNA sequence at a replication origin promotes repeat expansion to fragile X full mutation. PMID: 25179629. J Cell Biol. 2014 Sep 1;206(5):599-607. doi: 10.1083/jcb.201404157.
• This study shows that a substitution of cytosine for thymine appears to inactivate a replication origin in FXS hESCs increasing risk of repeat expansion to FXS.