The goal of this work is to correlate heparan sulfate structure with angiogenic function in vascular tissue. Both normal and pathological angiogenesis are mediated through growth factor stimuli that depend on the structures of cell surface and extracellular matrix heparan sulfate (HS) chains for receptor activation. HS serves as both a spatial and temporal regulator of growth factor activity during angiogenesis. The diversity of HS biological activities arises through their non-template driven biosynthesis. A series of modifying enzymes act upon nascent HS chains to produce mature molecules with characteristic domains of high and low sulfation. Chain lengths and degree of sulfation are heterogeneous and reflect the responses of cells to their growth environment. Variation in expression of HS chain structure is a mechanism whereby cells modulate their responses to growth factor stimuli. In this sense, the diversity of HS chains on cell surfaces and secreted proteins is a means of elaborating the functions of a limited array of growth factors and growth factor receptors. In vascular tissue, homeostasais and mitogenesis are controlled through growth factor signalling cascades. Fibroblast growth factors (FGFs), and their receptors bind HS chains on the cell surface and the extracellular matrix. At the present time, it is clear that both high and low affinity HS domains exist and play important roles in modulating angiogenic responses. Although it is also clear that such subsequences may either potentiate or inhibit growth factor, depending on the context, there is little information concerning their structures. In order to address these questions, new methods will be developed in Aim 1 to enable sequencing of HS compatible with on-line liquid chromatography-tandem mass spectrometry.
In Aim 2, libraries of organ-specific HS will be prepared using two dimensional chromatography. The structures will be determined using on-line tandem mass spectrometry and correlated with function using cell free growth factor binding and cellular mitogenesis assays.
Aim 3 is to determine the manner in which extracellular enzymes (mammalian endo- sulfatases and heparanase) remodel HS chains in biological systems.

Public Health Relevance

In vascular tissue, both normal and pathological cell growth related to angiogenesis is regulated through growth factor signaling cascades. Cells modulate their responses to growth factor signaling by altering the structures of heparan sulfate chains expressed on their surfaces and secreted into the extracellular matrix. This research will explore the structure-function relationships of vascular heparan sulfates in order to inform efforts to develop protein binding microarrays, drugs and therapeutics.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL098950-04
Application #
8402836
Study Section
Enabling Bioanalytical and Biophysical Technologies Study Section (EBT)
Program Officer
Sarkar, Rita
Project Start
2010-01-18
Project End
2013-12-31
Budget Start
2013-01-01
Budget End
2013-12-31
Support Year
4
Fiscal Year
2013
Total Cost
$382,883
Indirect Cost
$147,263
Name
Boston University
Department
Biochemistry
Type
Schools of Medicine
DUNS #
604483045
City
Boston
State
MA
Country
United States
Zip Code
02118
Turiák, Lilla; Shao, Chun; Meng, Le et al. (2014) Workflow for combined proteomics and glycomics profiling from histological tissues. Anal Chem 86:9670-8
Ramachandra, Rashmi; Namburi, Ramesh B; Ortega-Martinez, Olga et al. (2014) Brittlestars contain highly sulfated chondroitin sulfates/dermatan sulfates that promote fibroblast growth factor 2-induced cell signaling. Glycobiology 24:195-207
Huang, Yu; Mao, Yang; Buczek-Thomas, Jo Ann et al. (2014) Oligosaccharide substrate preferences of human extracellular sulfatase Sulf2 using liquid chromatography-mass spectrometry based glycomics approaches. PLoS One 9:e105143
Hu, Han; Huang, Yu; Mao, Yang et al. (2014) A computational framework for heparan sulfate sequencing using high-resolution tandem mass spectra. Mol Cell Proteomics 13:2490-502
Shao, Chun; Shi, Xiaofeng; Phillips, Joanna J et al. (2013) Mass spectral profiling of glycosaminoglycans from histological tissue surfaces. Anal Chem 85:10984-91
Shi, Xiaofeng; Shao, Chun; Mao, Yang et al. (2013) LC-MS and LC-MS/MS studies of incorporation of 34SO3 into glycosaminoglycan chains by sulfotransferases. Glycobiology 23:969-79
Gill, Vanessa Leah; Aich, Udayanath; Rao, Srinivasa et al. (2013) Disaccharide analysis of glycosaminoglycans using hydrophilic interaction chromatography and mass spectrometry. Anal Chem 85:1138-45
Zaia, Joseph (2013) Glycosaminoglycan glycomics using mass spectrometry. Mol Cell Proteomics 12:885-92
Nugent, M A; Zaia, J; Spencer, J L (2013) Heparan sulfate-protein binding specificity. Biochemistry (Mosc) 78:726-35
Zaia, Joseph (2013) Capillary electrophoresis-mass spectrometry of carbohydrates. Methods Mol Biol 984:13-25

Showing the most recent 10 out of 19 publications