Nitric oxide (NO) is a small, reactive molecule involved in numerous signaling pathways, including those regulating angiogenesis and metastasis. The primary cellular receptor for NO is soluble Guanylyl Cyclase (sGC), a heterodimeric hemoprotein of 150 kDa and an attractive target for the treatment of disease, including cancer. Binding of NO stimulates sGC activity, leading to the establishment of a cGMP signaling cascade. sGC is allosterically regulated by a variety of molecules, including NO, ATP, YC-1 (a small nucleotide-like pharmacophore), and by posttranslational modifications. Despite extensive study, little is known about the overall shape of sGC, the means by which allosteric regulation takes place, the arrangement of functional domains in the protein or the arrangement of the protein in the cell. We intend to fill this gap through fluorescence-based approaches that will allow us to measure structural changes within sGC, and also to monitor sGC localization within the cell. Specifically, we intend to incorporate paired fluorophores to full-length and truncated forms of sGC such that FRET measurements will reveal the distances between functional domains under stimulating and inhibiting conditions. We have developed a robust model system involving sGC from the hawk moth {Manduca sexta) with which to begin these studies, but will also include human sGC once the fluorescence system is established. We will investigate sGC conformational states not only with isolated material, but also in live cells. Additionally, we will use a combination of immunohistology and fluorescence microscopy to monitor localization of sGC under activating and inhibiting conditions. We have shown that sGC displays a punctuate arrangement in the cell, but the functional consequences of this stark pattern are unknown. Together, we expect that these studies will uncover the structural transitions that sGC undergoes and provide the framework for novel strategies in drug discovery. The generated results from this pilot project will provide the basis for future collaborative funding and research efforts.

Public Health Relevance

The Partnership for Native American Cancer Prevention is collaboration between Northern Arizona University and the Arizona Cancer Center. Its mission is to alleviate the unequal burden of cancer among Native Americans of the Southwest through research, training and outreach programs that are collaborative with the communities they serve.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Specialized Center--Cooperative Agreements (U54)
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Special Emphasis Panel (ZCA1-SRLB-D (O2))
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Ogunbiyi, Peter
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University of Arizona
Internal Medicine/Medicine
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United States
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Purohit, Rahul; Fritz, Bradley G; The, Juliana et al. (2014) YC-1 binding to the * subunit of soluble guanylyl cyclase overcomes allosteric inhibition by the * subunit. Biochemistry 53:101-14
Gustafson, Heather L; Yao, Song; Goldman, Bryan H et al. (2014) Genetic polymorphisms in oxidative stress-related genes are associated with outcomes following treatment for aggressive B-cell non-Hodgkin lymphoma. Am J Hematol 89:639-45
Karn, Robert C; Laukaitis, Christina M (2014) Selection shaped the evolution of mouse androgen-binding protein (ABP) function and promoted the duplication of Abp genes. Biochem Soc Trans 42:851-60
Briehl, Margaret M; Tome, Margaret E; Wilkinson, Sarah T et al. (2014) Mitochondria and redox homoeostasis as chemotherapeutic targets. Biochem Soc Trans 42:939-44
Janousek, Vaclav; Karn, Robert C; Laukaitis, Christina M (2013) The role of retrotransposons in gene family expansions: insights from the mouse Abp gene family. BMC Evol Biol 13:107
Nelson-Moseke, Anna C; Jeter, Joanne M; Cui, Haiyan et al. (2013) An unusual BRCA mutation distribution in a high risk cancer genetics clinic. Fam Cancer 12:83-7
Ramanathan, Saumya; Mazzalupo, Stacy; Boitano, Scott et al. (2011) Thrombospondin-1 and angiotensin II inhibit soluble guanylyl cyclase through an increase in intracellular calcium concentration. Biochemistry 50:7787-99