Effect of extension of the heparin binding pocket on the structure, stability, and cell proliferation activity of the human acidic fibroblast growth factor.


Abstract

Acidic human fibroblast growth factor (hFGF1) plays a key role in cell growth and proliferation. Activation of the cell surface FGF receptor is believed to involve the glycosaminoglycan, heparin. However, the exact role of heparin is a subject of considerable debate. In this context, in this study, the correlation between heparin binding affinity and cell proliferation activity of hFGF1 is examined by extending the heparin binding pocket through selective engineering via charge reversal mutations (D82R, D84R and D82R/D84R). Results of biophysical experiments such as intrinsic tryptophan fluorescence and far UV circular dichroism spectroscopy suggest that the gross native structure of hFGF1 is not significantly perturbed by the engineered mutations. However, results of limited trypsin digestion and ANS binding experiments show that the backbone structure of the D82R variant is more flexible than that of the wild type hFGF1. Results of the temperature and urea-induced equilibrium unfolding experiments suggest that the stability of the charge-reversal mutations increases in the presence of heparin. Isothermal titration calorimetry (ITC) data reveal that the heparin binding affinity is significantly increased when the charge on D82 is reversed but not when the negative charge is reversed at both positions D82 and D84 (D82R/D84R). However, despite the increased affinity of D82R for heparin, the cell proliferation activity of the D82R variant is observed to be reduced compared to the wild type hFGF1. The results of this study clearly demonstrate that heparin binding affinity of hFGF1 is not strongly correlated to its cell proliferation activity.

Submission Details

ID: jXbeHAoc3

Submitter: Shu-Ching Ou

Submission Date: March 28, 2019, 12:27 p.m.

Version: 1

Publication Details
Davis JE;Gundampati RK;Jayanthi S;Anderson J;Pickhardt A;Koppolu BP;Zaharoff DA;Kumar TKS,Biochem Biophys Rep (2018) Effect of extension of the heparin binding pocket on the structure, stability, and cell proliferation activity of the human acidic fibroblast growth factor. PMID:29556563
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P
 

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)


Relevant PDB Entries

Structure ID Release Date Resolution Structure Title
2UUS 2007-03-07T00:00:00+0000 2.2 Crystal structure of the rat FGF1-sucrose octasulfate (SOS) complex.
1AFC 1993-07-13T00:00:00+0000 2.7 STRUCTURAL STUDIES OF THE BINDING OF THE ANTI-ULCER DRUG SUCROSE OCTASULFATE TO ACIDIC FIBROBLAST GROWTH FACTOR
2J3P 2006-08-22T00:00:00+0000 1.4 crystal structure of rat FGF1 at 1.4 A
1BAR 1992-09-29T00:00:00+0000 2.7 THREE-DIMENSIONAL STRUCTURES OF ACIDIC AND BASIC FIBROBLAST GROWTH FACTORS
1K5V 2001-10-12T00:00:00+0000 2.1 Human acidic fibroblast growth factor. 141 amino acid form with amino terminal His tag with Asn106 replaced by Gly (N106G).
1K5U 2001-10-12T00:00:00+0000 2.0 Human acidic fibroblast growth factor. 141 amino acid form with amino terminal His tag with His93 replaced by Gly (H93G).
2K8R 2008-09-22T00:00:00+0000 0 Solution structure of human acidic fibroblast growth factor in complex with anti-angiogenic drug inositol hexaphosphate (IP6)
3BA5 2007-11-07T00:00:00+0000 1.75 Crystal structure of D28A mutant of Human acidic fibroblast growth factor
3BA4 2007-11-07T00:00:00+0000 1.8 Crystal structure of L26D mutant of Human acidic fibroblast growth factor
3BA7 2007-11-07T00:00:00+0000 1.6 Crystal structure of L26N/D28A mutant of Human acidic fibroblast growth factor

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
91.5 Fibroblast growth factor 1 Q9N1S8 FGF1_CAPCA
90.6 Fibroblast growth factor 1 P19596 FGF1_CHICK
90.6 Fibroblast growth factor 1 Q7M303 FGF1_SHEEP
92.1 Fibroblast growth factor 1 P03968 FGF1_BOVIN
97.8 Fibroblast growth factor 1 P20002 FGF1_PIG
96.4 Fibroblast growth factor 1 P61149 FGF1_RAT
96.4 Fibroblast growth factor 1 P61148 FGF1_MOUSE
97.8 Fibroblast growth factor 1 P34004 FGF1_MESAU
100.0 Fibroblast growth factor 1 Q5NVQ3 FGF1_PONAB
100.0 Fibroblast growth factor 1 P05230 FGF1_HUMAN