Intracellular switching using genetically engineered protein microdomains Biology is unparalleled in the replication of complex structures with diverse functions on the molecular and cellular scale; however, our ability to engineer functional materials at or below the size of the cell remains primitive. By using biological materials to assemble structures, process information, and harness energy, the emerging field of synthetic biology may bridge the gap between current technology and that needed to study and intervene in disease. Towards this futuristic goal, this project elaborates on a platform discovered by our team to control functional structures that are 10-1000 times smaller than a cell. These structures are based on polypeptides; therefore, they can be encoded in DNA and grown inside of living cells. Our group recently reported that temperature-responsive protein polymers expressed in the cytosol assemble organelle-sized structures within minutes of an increase of 1 degree Celsius. We named these structures genetically engineered protein microdomains, reported that they can either sort or co-assemble intact fusion proteins, and that their assembly can control a model cellular internalization pathway called clathrin-mediated endocytosis. Now we present preliminary evidence that these microdomains can activate a model cell-surface receptor and drive its internalization. This research project is designed to validate and expand the potential applications for these microdomains. The overall hypothesis is that through design, these microdomains can stimulate, deactivate, or respond to target cellular processes.
Three aims are proposed:
Aim 1) Manipulation of endocytotic pathways using microdomains;
Aim 2) Interrogating cell signaling using ELP microdomains;
and Aim 3) Expanding microdomain technology. This application innovates in three main ways: i) our interdisciplinary team is the first to report that intracellular ELPs generate microdomains that exert control over cellular pathways; ii) unlike traditional mechanisms for modulating protein activity, ELP microdomains can be activated or deactivated rapidly in live cells; and iii) this project will generalize these strategies so that they can be used to target a broad array of cellular functions. The successful demonstration of this approach is intended to shift the paradigm for how cellular biology studies are performed, enabling precise manipulation of biological processes that are fundamentally important to drug discovery. A comprehensive series of studies will be performed to demonstrate the breadth of potential applications for microdomain assembly within the cell. When completed, this project will deliver a biomolecular toolbox of broad utility to study biological processes associated with human disease.

Public Health Relevance

Understanding the process by which diseases, such as cancer or infection, proceed at a molecular and cellular level is critical to developing new treatments. This research project will explore the full potential of a novel, enabling technology that rapidly turns `on' and `off' target cellular processes. Successful dissemination of this technology will catalyze new insights into disease processes, the discovery of new drugs, and improved treatments for disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM114839-03
Application #
9243278
Study Section
Biomaterials and Biointerfaces Study Section (BMBI)
Program Officer
Maas, Stefan
Project Start
2015-04-01
Project End
2020-03-31
Budget Start
2017-04-01
Budget End
2018-03-31
Support Year
3
Fiscal Year
2017
Total Cost
Indirect Cost
Name
University of Southern California
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
072933393
City
Los Angeles
State
CA
Country
United States
Zip Code
90033
Peddi, Santosh; Pan, Xiaoli; MacKay, John Andrew (2018) Intracellular Delivery of Rapamycin From FKBP Elastin-Like Polypeptides Is Consistent With Macropinocytosis. Front Pharmacol 9:1184
Guo, Hao; Lee, Changrim; Shah, Mihir et al. (2018) A novel elastin-like polypeptide drug carrier for cyclosporine A improves tear flow in a mouse model of Sjögren's syndrome. J Control Release 292:183-195
Dhandhukia, Jugal P; Shi, Pu; Peddi, Santosh et al. (2017) Bifunctional Elastin-like Polypeptide Nanoparticles Bind Rapamycin and Integrins and Suppress Tumor Growth in Vivo. Bioconjug Chem 28:2715-2728
Dhandhukia, Jugal P; Li, Zhe; Peddi, Santosh et al. (2017) Berunda Polypeptides: Multi-Headed Fusion Proteins Promote Subcutaneous Administration of Rapamycin to Breast Cancer In Vivo. Theranostics 7:3856-3872
Dhandhukia, Jugal P; Brill, Dab A; Kouhi, Aida et al. (2017) Elastin-like polypeptide switches: A design strategy to detect multimeric proteins. Protein Sci 26:1785-1795
Pastuszka, Martha K; MacKay, J Andrew (2016) Engineering structure and function using thermoresponsive biopolymers. Wiley Interdiscip Rev Nanomed Nanobiotechnol 8:123-38
Despanie, Jordan; Dhandhukia, Jugal P; Hamm-Alvarez, Sarah F et al. (2016) Elastin-like polypeptides: Therapeutic applications for an emerging class of nanomedicines. J Control Release 240:93-108
Hsueh, Pang-Yu; Edman, Maria C; Sun, Guoyong et al. (2015) Tear-mediated delivery of nanoparticles through transcytosis of the lacrimal gland. J Control Release 208:2-13
Brill, Dab A; MacKay, J Andrew (2015) Image-driven pharmacokinetics: nanomedicine concentration across space and time. Nanomedicine (Lond) 10:2861-79