BBS Faculty Member - Stephen Blacklow

Stephen Blacklow

Department of Biological Chemistry and Molecular Pharmacology

Harvard Medical School
LHRRB Building, Room 201B
240 Longwood Ave.
Boston, MA 02115
Tel: 617-432-5176
Fax: 617-525-4414
Lab Members: 8 postdoctoral fellows
Visit my lab page here.

The long-term goal of our research program is to understand the molecular logic of cell-surface receptors, focusing on proteins implicated in human disease. The laboratory currently emphasizes structure-function studies in Notch signaling and maintains an ongoing interest in proteins of the LDL receptor family.

Notch proteins are single-pass transmembrane receptors that convey signals upon activation by transmembrane ligands expressed on neighboring cells. The signals transduced by Notch receptors play a central role in cell fate decisions both during embryonic development and in adult tissue homeostasis. Ligand binding initiates signaling by triggering a process called regulated intramembrane proteolysis, releasing the intracellular part of Notch (ICN) from the membrane. In canonical Notch signaling, ICN ultimately enters the nucleus, where it assembles into a transcriptional activation complex to induce the expression of Notch target genes. Although Notch receptors are large and complex, all family members contain an extracellular ligand-binding domain, a conserved extracellular juxtamembrane region that maintains the receptor in a resting conformation prior to ligand-induced activation, and an intracellular ankyrin repeat domain required to activate transcription. Mutations in the juxtamembrane region cause increased signaling and occur frequently in human T-cell acute leukemias (T-ALL), identifying Notch as a therapeutic target in these tumors. Our current efforts are directed toward understanding how activation is induced by ligands, how Notch cooperates with other factors to regulate target gene transcription, and how to inhibit Notch1 as a potential treatment for the aberrant signaling that occurs in more than half of human T-ALLs.

Last Update: 3/11/2015


For a complete listing of publications click here.



Tiyanont, K, Wales, TE, Aste-Amezaga, M, Aster, JC, Engen, JR, and Blacklow, SC. Evidence for Increased Exposure of the Notch1 Metalloprotease Cleavage Site upon Conversion to an Activated Conformation. Structure 2011;19(4):546-54.

Arnett, KA, Hass, M, McArthur, DG, Ilagan, MXG, Aster, JC, Kopan, R, and Blacklow SC. Structural and Mechanistic Insights into Cooperative Assembly of Dimeric Notch Transcription Complexes. Nature Structural and Molecular Biology 2010;17(11):1312-7 (Cover article).

Nam, Y, Sliz, P, Pear, WS, Aster, JC, and Blacklow, SC. Cooperative assembly of higher order Notch complexes functions as a switch to induce transcription. Proc Natl Acad Sci, 2007;104(7):2103-2108.

Gordon, WR, Vardar-Ulu, D, Sanchez-Irizarry, C, Histen, G, Aster, JC, and Blacklow, SC. Structural Basis for Autoinhibition of Notch. Nat Struct and Mol Biol 2007; 14(4):295-300.

Nam, Y., Sliz, P., Song, L., Aster, JC, and Blacklow, SC. Structural basis for cooperativity in recruitment of MAML co-activators to Notch transcription complexes. Cell, 2006; 124, 973-983.

© 2015 by the President and Fellows of Harvard College