Probing the role of proline -135 on the structure, stability, and cell proliferation activity of human acidic fibroblast growth factor.


Abstract

Human acidic fibroblast growth factor 1 (hFGF1) is a protein intricately involved in cell growth and tissue repair. In this study, we investigate the effect(s) of understanding the role of a conserved proline (P135), located in the heparin binding pocket, on the structure, stability, heparin binding affinity, and cell proliferation activity of hFGF1. Substitution of proline-135 with a positively charged lysine (P135K) resulted in partial destabilization of the protein; however, the overall structural integrity of the protein was maintained upon substitution of proline-135 with either a negative charge (P135E) or a polar amino acid (P135Q). Interestingly, upon heparin binding, an increase in thermal stability equivalent to that of wt-hFGF1 was observed when P135 was replaced with a positive (P135K) or a negative charge (P135E), or with a polar amino acid (P135Q). Surprisingly, introduction of negative charge in the heparin-binding pocket at position 135 (P135E) increased hFGF1's affinity for heparin by 3-fold, while the P135K mutation, did not alter the heparin-binding affinity. However, the enhanced heparin-binding affinity of mutant P135E did not translate to an increase in cell proliferation activity. Interestingly, the P135K and P135E double mutations, P135K/R136E and P135/R136E, reduced the heparin binding affinity by ∼3-fold. Furthermore, the cell proliferation activity was increased when the charge reversal mutation R136E was paired with both P135E (P135E/R136E) and P135K (P135K/R136E). Overall, the results of this study suggest that while heparin is useful for stabilizing hFGF1 on the cell surface, this interaction is not mandatory for activation of the FGF receptor.

Submission Details

ID: SgQVErXY

Submitter: Connie Wang

Submission Date: Sept. 28, 2018, 4:24 p.m.

Version: 1

Publication Details
Davis JE;Alghanmi A;Gundampati RK;Jayanthi S;Fields E;Armstrong M;Weidling V;Shah V;Agrawal S;Koppolu BP;Zaharoff DA;Kumar TKS,Arch Biochem Biophys (2018) Probing the role of proline -135 on the structure, stability, and cell proliferation activity of human acidic fibroblast growth factor. PMID:30031837
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
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
1BAR 1992-09-29T00:00:00+0000 2.7 THREE-DIMENSIONAL STRUCTURES OF ACIDIC AND BASIC FIBROBLAST GROWTH FACTORS
2J3P 2006-08-22T00:00:00+0000 1.4 crystal structure of rat FGF1 at 1.4 A
2UUS 2007-03-07T00:00:00+0000 2.2 Crystal structure of the rat FGF1-sucrose octasulfate (SOS) complex.
1AXM 1997-10-16T00:00:00+0000 3.0 HEPARIN-LINKED BIOLOGICALLY-ACTIVE DIMER OF FIBROBLAST GROWTH FACTOR
1DJS 1999-12-03T00:00:00+0000 2.4 LIGAND-BINDING PORTION OF FIBROBLAST GROWTH FACTOR RECEPTOR 2 IN COMPLEX WITH FGF1
1DZC 2000-02-24T00:00:00+0000 0 High resolution structure of acidic fibroblast growth factor. Mutant FGF-4-ALA-(24-154), 24 NMR structures
1DZD 2000-02-24T00:00:00+0000 0 High resolution structure of acidic fibroblast growth factor (27-154), 24 NMR structures
1E0O 2000-04-03T00:00:00+0000 2.8 CRYSTAL STRUCTURE OF A TERNARY FGF1-FGFR2-HEPARIN COMPLEX
1EVT 2000-04-20T00:00:00+0000 2.8 CRYSTAL STRUCTURE OF FGF1 IN COMPLEX WITH THE EXTRACELLULAR LIGAND BINDING DOMAIN OF FGF RECEPTOR 1 (FGFR1)

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Fibroblast growth factor 1 P05230 FGF1_HUMAN
100.0 Fibroblast growth factor 1 Q5NVQ3 FGF1_PONAB
96.8 Fibroblast growth factor 1 P34004 FGF1_MESAU
98.0 Fibroblast growth factor 1 P20002 FGF1_PIG
95.5 Fibroblast growth factor 1 P61148 FGF1_MOUSE
95.5 Fibroblast growth factor 1 P61149 FGF1_RAT
92.3 Fibroblast growth factor 1 P03968 FGF1_BOVIN
90.3 Fibroblast growth factor 1 Q7M303 FGF1_SHEEP
90.3 Fibroblast growth factor 1 P19596 FGF1_CHICK
91.5 Fibroblast growth factor 1 Q9N1S8 FGF1_CAPCA