Electrolyte homeostasis is essential for life at the cellular level, in that, cells must respond to osmotic challenge to fend off changes in cellular water and ion content that could lead to rupture. On a larger scale, humans regulate blood pressure by maintaining an appropriate balance of sodium reabsorption and excretion in the kidney. Hypertension, a major health problem affecting more than 60 million Americans, is a result of a dysfunction in electrolyte homeostasis. Therefore, understanding mechanisms that control electrolyte homeostasis is important for human health. It is becoming increasingly clear that a core set of regulatory proteins senses and maintains electrolyte homeostasis. Our knowledge is lacking in how this is achieved at the molecular level. The molecular mechanisms of electrolyte homeostasis are of critical importance for both healthy and disease states in humans and thus must be understood in order unlock their therapeutic potential.
We aim to understand the network of proteins and signaling mechanisms, mainly regulatory phosphorylation events, which connect mechanisms of cell volume control and blood pressure homeostasis. The red blood cell holds great potential as a model system to understand the fundamental elements critical for electrolyte homeostasis. We will use a quantitative proteomic approach to study networks of signaling proteins that regulate electrolyte flux in red blood cells. We will focus our studies on the K-Cl cotransporters as a representative direct mediator of electrolyte flux and the kinases Wnk1 and Wnk4 as critical signaling components of ion flux. These studies will provide new insight into the upstream regulation of Wnk function and downstream signaling events that control electrolyte homeostasis by identifying critical regulatory phosphorylation sites. To link these observations to the in vivo setting, we will use SILAC technology in the mouse red blood cell to quantify critical regulatory phosphorylation sites that respond to specific physiologic perturbation. The purpose of this study is to provide a fundamental understanding of the mechanisms that coordinate electrolyte homeostasis. Furthermore, we are seeking mechanistic links in blood pressure control and cell volume regulation in order to find new target points to treat diseases such as hypertension and sickle cell anemia.

Public Health Relevance

The purpose of this study is to provide a fundamental understanding of the mechanisms that coordinate electrolyte homeostasis. Hypertension, a major health problem affecting more than 60 million Americans, is a result of a dysfunction in electrolyte homeostasis. Therefore, understanding mechanisms that control electrolyte homeostasis is important for human health.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Scientist Development Award - Research & Training (K01)
Project #
5K01DK089006-03
Application #
8321094
Study Section
Diabetes, Endocrinology and Metabolic Diseases B Subcommittee (DDK)
Program Officer
Rankin, Tracy L
Project Start
2010-09-02
Project End
2015-08-31
Budget Start
2012-09-01
Budget End
2013-08-31
Support Year
3
Fiscal Year
2012
Total Cost
$154,332
Indirect Cost
$11,432
Name
Yale University
Department
Genetics
Type
Schools of Medicine
DUNS #
043207562
City
New Haven
State
CT
Country
United States
Zip Code
06520
Steinfeld, Justin B; Aerni, Hans R; Rogulina, Svetlana et al. (2014) Expanded cellular amino acid pools containing phosphoserine, phosphothreonine, and phosphotyrosine. ACS Chem Biol 9:1104-12
Shibata, Shigeru; Rinehart, Jesse; Zhang, Junhui et al. (2013) Mineralocorticoid receptor phosphorylation regulates ligand binding and renal response to volume depletion and hyperkalemia. Cell Metab 18:660-71
Zhang, Chengbiao; Wang, Lijun; Thomas, Sherin et al. (2013) Src family protein tyrosine kinase regulates the basolateral K channel in the distal convoluted tubule (DCT) by phosphorylation of KCNJ10 protein. J Biol Chem 288:26135-46
Lajoie, Marc J; Rovner, Alexis J; Goodman, Daniel B et al. (2013) Genomically recoded organisms expand biological functions. Science 342:357-60
Krishnakumar, Radha; Prat, Laure; Aerni, Hans-Rudolf et al. (2013) Transfer RNA misidentification scrambles sense codon recoding. Chembiochem 14:1967-72
Zarychanski, Ryan; Schulz, Vincent P; Houston, Brett L et al. (2012) Mutations in the mechanotransduction protein PIEZO1 are associated with hereditary xerocytosis. Blood 120:1908-15
Lin, Dao-Hong; Yue, Peng; Rinehart, Jesse et al. (2012) Protein phosphatase 1 modulates the inhibitory effect of With-no-Lysine kinase 4 on ROMK channels. Am J Physiol Renal Physiol 303:F110-9
Park, Hee-Sung; Hohn, Michael J; Umehara, Takuya et al. (2011) Expanding the genetic code of Escherichia coli with phosphoserine. Science 333:1151-4