The focal distribution of atherosclerotic lesions in the arterial tree is attributable to the exposure of the vascular endothelial cells (ECs) to the atheroprone oscillatory shear (OS) at vessel branch points and curvatures, in contrast to the atheroprotective pulsatile shear (PS) at straight parts of the vessel. These two types of flow patterns induce distinct expression profiles of miRNAs (miRs) that differentially regulate the expression of target geness, resulting in distinct functional outcomes. Nucleolin (NCL) is a multi-functional protein that plays critical roles in regulating cell functions through epigenetic, transcriptional, post-transcriptional, and translational regulations. We propose that NCL regulates miRome (miR transcription and maturation) through its interactions with DNA (via g-quadruplex sequences) and RNA (via UCCCGA consensus sequence). Our preliminary results have demonstrated that PS induces the phosphorylation of NCL that leads to an increased binding of NCL to the promoter/enhancer regions of miR23b/27b to increase miR transcription. On the other hand, under OS, the non- phosphorylated NCL binds to miR93/miR484 and Drosha to facilitate miR maturation. These novel findings have led to the hypothesis of this renewal proposal: NCL is differentially regulated by atheroprotective and atheroprone flow patterns to modulate the miRome at transcriptional and maturation levels, thus playing an important role in vascular homeostasis in health and disease. To test this hypothesis, we propose the following four Specific Aims: 1) to examine the molecular mechanisms underlying PS- vs. OS-regulation of NCL in miR transcriptome, 2) to determine the molecular mechanisms underlying PS- vs. OS-regulation of NCL- modulated miR maturation, 3) to integrate the multi-layer regulations of miRome by NCL and the functional consequences under PS and OS with the use of systems approaches, 4) to validate the role of NCL in regulating vascular function in vivo. In the proposed research, we will use a combination of in vitro endothelial cell biology, in vivo mouse models, in silico network construction/data mining, and clinical samples derived from patients with cardiovascular diseases to decipher the mechanisms of flow modulation of NCL-regulation of miRome. The findings will result in novel understanding of the role of NCL in regulating vascular functions in health and disease via miR regulations. !

Public Health Relevance

We propose to use the systems biology approach combining in vitro, in vivo, and in silico experimental procedures, as well as human specimens, to elucidate the flow-regulation of nucleolin to modulate microRNA transcription and maturation, as well as the targeted gene expression in vascular endothelial cells. The resultant mechanistic and regulatory network models will provide critical information on vascular biology in normal and pathophysiological conditions. The study will also provide novel knowledge for the prevention, treatment, and management of vascular diseasses.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL106579-11
Application #
10065006
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Hasan, Ahmed a K
Project Start
2011-01-01
Project End
2022-11-30
Budget Start
2020-12-01
Budget End
2021-11-30
Support Year
11
Fiscal Year
2021
Total Cost
Indirect Cost
Name
University of California, San Diego
Department
Biomedical Engineering
Type
Schools of Arts and Sciences
DUNS #
804355790
City
La Jolla
State
CA
Country
United States
Zip Code
92093
Yeh, Yi-Ting; Serrano, Ricardo; François, Joshua et al. (2018) Three-dimensional forces exerted by leukocytes and vascular endothelial cells dynamically facilitate diapedesis. Proc Natl Acad Sci U S A 115:133-138
Diez-Cuñado, Marta; Wei, Ke; Bushway, Paul J et al. (2018) miRNAs that Induce Human Cardiomyocyte Proliferation Converge on the Hippo Pathway. Cell Rep 23:2168-2174
Miao, Yifei; Ajami, Nassim E; Huang, Tse-Shun et al. (2018) Enhancer-associated long non-coding RNA LEENE regulates endothelial nitric oxide synthase and endothelial function. Nat Commun 9:292
Tsimikas, Sotirios (2018) In search of a physiological function of lipoprotein(a): causality of elevated Lp(a) levels and reduced incidence of type 2 diabetes. J Lipid Res 59:741-744
Tsimikas, Sotirios; Fazio, Sergio; Ferdinand, Keith C et al. (2018) NHLBI Working Group Recommendations to Reduce Lipoprotein(a)-Mediated Risk of Cardiovascular Disease and Aortic Stenosis. J Am Coll Cardiol 71:177-192
Senders, Max L; Que, Xuchu; Cho, Young Seok et al. (2018) PET/MR Imaging of Malondialdehyde-Acetaldehyde Epitopes With a Human Antibody Detects Clinically Relevant Atherothrombosis. J Am Coll Cardiol 71:321-335
Torzewski, Michael; Ravandi, Amir; Yeang, Calvin et al. (2017) Lipoprotein(a) Associated Molecules are Prominent Components in Plasma and Valve Leaflets in Calcific Aortic Valve Stenosis. JACC Basic Transl Sci 2:229-240
Moriarty, Patrick M; Varvel, Stephen A; Gordts, Philip L S M et al. (2017) Lipoprotein(a) Mass Levels Increase Significantly According to APOE Genotype: An Analysis of 431?239 Patients. Arterioscler Thromb Vasc Biol 37:580-588
Yeang, Calvin; Gordts, Philip L S M; Tsimikas, Sotirios (2017) Novel Lipoprotein(a) Catabolism Pathway via Apolipoprotein(a) Recycling: Adding the Plasminogen Receptor PlgRKT to the List. Circ Res 120:1050-1052
He, Ming; Chen, Zhen; Martin, Marcy et al. (2017) miR-483 Targeting of CTGF Suppresses Endothelial-to-Mesenchymal Transition: Therapeutic Implications in Kawasaki Disease. Circ Res 120:354-365

Showing the most recent 10 out of 58 publications