Research Description

Interactome networks of integral membrane proteins and their roles in health & disease

A key focus of the Stagljar lab is to understand the function of a wide range of pharmaceutically relevant yeast and human integral membrane proteins involved in cell signaling and membrane transport at a systems level. Despite extensive research in the past decade, there is a lack of in-depth understanding of protein networks associated with these integral membrane proteins because of their unique biochemical features, enormous complexity and multiplicity. This is a major obstacle for designing improved and more targeted therapies, and importantly, understanding the biology of deregulation of these integral membrane proteins which leads to numerous human diseases.

Our lab is internationally known for the development of the split-ubiquitin Membrane Yeast Two-Hybrid (MYTH) and Mammalian Membrane Two-Hybrid (MaMTH) technologies, powerful tools for the identification of interactors of a given integral membrane protein and one of the key interactive proteomic technologies available to researchers today. To date, MYTH and MaMTH have lead to many groundbreaking discoveries, including the elucidation of functions of various integral membrane proteins involved in human health and disease.

Currently, there are several large-scale, ongoing projects in the lab aimed towards elucidating how yeast and human integral membrane proteins and their interacting partners lead to either diseased or healthy states. These studies include mapping of protein interaction networks of various families of membrane proteins such as ABC Transporters, Receptor Tyrosine Kinases, G-protein Coupled Receptors, Cancer Stem Cell Receptors and Ion Channels. Subsequently, proteins and pathways identified by our initial protein interaction screens are studied in depth using various genetic, molecular, and biochemical approaches, shedding light on cell signaling and membrane transport pathways, which control cell behavior in normal and disease cells at a systems level.

In addition, because the Stagljar group studies ‘druggable’ membrane proteins, they hope their work will unveil new avenues for diagnosis and treatment of many human diseases.

Proteomics

A key focus of our lab is to understand the function of a wide range of pharmaceutically relevant yeast and human integral membrane proteins involved in cell signaling and membrane transport at a systems level. Despite extensive research in the past decade, there is a lack of in-depth understanding of protein networks associated with these integral membrane proteins because of their unique biochemical features, enormous complexity and multiplicity. This is a major obstacle for designing improved and more targeted therapies, and importantly, understanding the biology of deregulation of these integral membrane proteins which leads to numerous human diseases.

Our lab is internationally known for the development of the split-ubiquitin Membrane Yeast Two-Hybrid (MYTH) and Mammalian Membrane Two-Hybrid (MaMTH) technologies, powerful tools for the identification of interactors of a given integral membrane protein and one of the key interactive proteomic technologies available to researchers today. To date, MYTH and MaMTH have lead to many groundbreaking discoveries, including the elucidation of functions of various integral membrane proteins involved in human health and disease.

Currently, there are several large-scale on-going projects in the lab aimed towards elucidating how yeast and human integral membrane proteins and their interacting partners lead to either diseased or healthy states. These studies include mapping of protein interaction networks of various families of membrane proteins such as ABC Transporters, Receptor Tyrosine Kinases, G-protein Coupled Receptors, Cancer Stem Cell Receptors and Ion Channels. Subsequently, proteins and pathways identified by our initial protein interaction screens are studied in depth using various genetic, molecular, and biochemical approaches, shedding light on cell signaling and membrane transport pathways, which control cell behavior in normal and disease cells at a systems level.

Cell Signaling

Our lab studies abnormal proteins on the surface of human cells (also called receptors), which are associated with non-small cell lung cancer (NSCLC) using a newly developed MaMTH technology in hopes of getting a better understanding of this widespread and deadly form of cancer. Using this new technology, we recently identified a key protein called CRK II which interacts with the oncogenic version of EGFR, and which, when synthesized in large quantities, stimulates the growth of NSCLC cells. We now study in detail the exact role of CRK II in the onset and progression of NSCLC.

By applying our newly developed MaMTH technology, we hope to identify additional proteins that interact with oncogenic version of EGFR and regulate the proliferation of NSCLC cells. In summary, our work will add greatly to the field and provide other researchers with new knowledge, and potential new drug targets, to help combat NSCLC.

Membrane Transport

ABC Binding Cassette (ABC) proteins comprise one of the largest known protein superfamilies, using the power of nucleotide binding and hydrolysis to mediate a diverse range of cellular functions. A major class of ABC proteins are the integral membrane ABC transporters, which are responsible for the movement of a wide variety of substances across cellular membranes. ABC transporters are of great clinical interest because of the key roles they play in human health and disease. Dysfunction of ABC transporters is associated with a variety of human diseases, such as cystic fibrosis, pseudoxanthoma elasticum, adrenoleukodystrophy, Zellweger syndrome, familial hyperinsulinemic hypoglycemia of infancy, Dubin-Johnson syndrome, hepatic cholestasis, the retinal syndrome Stargardt’s dystrophy, and the cholesterol transport disorder Tangier disease. ABC transporters are also associated with multidrug resistance of cancer cells and pathogenic microorganisms, and can provide a serious barrier to effective drug therapy.

In an effort to gain a better understanding of the regulation and molecular function of these proteins we recently used the MYTH system to map the complete interactome of all non-mitochondrial ABC transporters found in the yeast Saccharomyces cerevisiae. Our results revealed that ABC transporters physically associate with a functionally diverse array of proteins and show far greater integration with cellular systems than previously known. We are currently seeking to expand upon this work by using our powerful new MaMTH technology to map the interactions of the complete complement of ABC transporters found in humans.

Publications

View all publications on PubMed

A Comprehensive Membrane Interactome Mapping of Sho1p Reveals Fps1p as a Novel Key Player in the Regulation of the HOG Pathway in S. cerevisiae
Lam, M.H.Y, Snider, J., Rehal, M., Wong, V., Aboualizadeh, F., Drecun, L., Wong, O., Jubran, B., Li, M., Ali, M., Jessulat, M., Deineko, V., Miller, R., Lee, M., Park, H-O., Davidson, A., Babu, M., and Stagljar, I.
J Mol Biol. 2015 Jun 5;427(11):2088-103. doi: 10.1016/j.jmb.2015.01.016. Epub 2015 Jan 30.  Read

Application Guide for OMICs Approaches to Cell Signaling
Yao, Z., Petschnigg, J., Ketteler, R., and Stagljar, I.
Nat Chem Biol. 2015 Jun;11(6):387-97. doi: 10.1038/nchembio.1809. Epub 2015 May 15  Read

Fundamentals of protein interaction mapping
Snider, J., Kotlyar, M., Saraon, P., Yao, Z., Jurisica, I., and Stagljar, I.
Mol Syst Biol. 2015 Dec; 11(12): 848. Published online 2015 Dec 17. doi: 10.15252/msb.20156351  Read

The mammalian-membrane two-hybrid assay (MaMTH) for probing membrane-protein interactions in human cells
Petschnigg J, Groisman B, Kotlyar M, Taipale M, Zheng Y, Kurat CF, Sayad A, Sierra JR, Mattiazzi Usaj M, Snider J, Nachman A, Krykbaeva I, Tsao MS, Moffat J, Pawson T, Lindquist S, Jurisica I, Stagljar I.
Nat Methods. 2014 May;11(5):585-92. doi: 10.1038/nmeth.2895. Epub 2014 Mar 23.  Read

Mapping the functional yeast ABC transporter interactome
Snider J, Hanif A, Lee ME, Jin K, Yu AR, Graham C, Chuk M, Damjanovic D, Wierzbicka M, Tang P, Balderes D, Wong V, Jessulat M, Darowski KD, San Luis BJ, Shevelev I, Sturley SL, Boone C, Greenblatt JF, Zhang Z, Paumi CM, Babu M, Park HO, Michaelis S, Stagljar I.
Nat Chem Biol. 2013 Sep;9(9):565-72. doi: 10.1038/nchembio.1293. Epub 2013 Jul 7.  Read

Regulation of CD133 by HDAC6 promotes β-catenin signaling to suppress cancer cell differentiation
Mak AB, Nixon AM, Kittanakom S, Stewart JM, Chen GI, Curak J, Gingras AC, Mazitschek R, Neel BG, Stagljar I, Moffat J.
Cell Rep. 2012 Oct 25;2(4):951-63. doi: 10.1016/j.celrep.2012.09.016. Epub 2012 Oct 19.  Read

Interaction landscape of membrane-protein complexes in Saccharomyces cerevisiae
Babu M, Vlasblom J, Pu S, Guo X, Graham C, Bean BD, Burston HE, Vizeacoumar FJ, Snider J, Phanse S, Fong V, Tam YY, Davey M, Hnatshak O, Bajaj N, Chandran S, Punna T, Christopolous C, Wong V, Yu A, Zhong G, Li J, Stagljar I, Conibear E, Wodak SJ, Emili A, Greenblatt JF.
Nature. 2012 Sep 27;489(7417):585-9. doi: 10.1038/nature11354. Epub 2012 Sep 2.  Read

Regulation of epidermal growth factor receptor trafficking by lysine deacetylase HDAC6
Deribe YL, Wild P, Chandrashaker A, Curak J, Schmidt MH, Kalaidzidis Y, Milutinovic N, Kratchmarova I, Buerkle L, Fetchko MJ, Schmidt P, Kittanakom S, Brown KR, Jurisica I, Blagoev B, Zerial M, Stagljar I, Dikic I.
Sci Signal. 2009 Dec 22;2(102):ra84. doi: 10.1126/scisignal.2000576.  Read

Mapping protein-protein interactions for the yeast ABC transporter Ycf1p by integrated split-ubiquitin membrane yeast two-hybrid analysis
Paumi CM, Menendez J, Arnoldo A, Engels K, Iyer KR, Thaminy S, Georgiev O, Barral Y, Michaelis S, Stagljar I.
Mol Cell. 2007 Apr 13;26(1):15-25.  Read