Solution structures of human transforming growth factor .alpha. derived from 1H NMR data

Abstract

The 600-MHz 1H NMR spectrum of the des-Val-Val mutant of human transforming growth factor alpha (TGF-alpha) was reassigned at pH = 6.3. The conformation space of des-Val-Val TGF-alpha was explored by distance geometry embedding followed by restrained molecular dynamics refinement using NOE distance constraints and some torsion angle constraints derived from J-couplings. Over 80 long-range NOE constraints were found by completely assigning all resolved cross-peaks in the NOESY spectra. Low NOE constraint violations were observed in structures obtained with the following three different refinement procedures: interactive annealing in DSPACE, AMBER 3.0 restrained molecular dynamics, and dynamic simulated annealing in XPLOR. The segment from Phe15 to Asp47 was found to be conformationally well-defined. Back-calculations of NOESY spectra were used to evaluate the quality of the structures. Our calculated structures resemble the ribbon diagram presentations that were recently reported by other groups. Several side-chain conformations appear to be well-defined as does the relative orientation of the C loop to the N-terminal half of the protein.

Five carboxyl-terminal residues of neuregulin2 are critical for stimulation of signaling by the ErbB4 receptor tyrosine kinase

“…Substitution of an alanine for Arg45 of EGF (which corresponds to Phe45 of NRG2b) results in a marked increase in the ligand affinity for the chicken EGF receptor (van de Poll et al, 1995). As determined by two-dimensional 1 H NMR, the carboxyl-terminal tails of both EGF and TGFa are flexible in solution (Kline et al, 1990;Kohda and Inagaki, 1992). However, Figure 6 NRG2a gain-of-function mutants stimulate modest EGFR and ErbB4 tyrosine phosphorylation in BaF3/EGFR þ ErbB4 cells.…”

Simulated annealing with restrained molecular dynamics using CONGEN: Energy refinement of the NMR solution structures of epidermal and type‐α transforming growth factors

“…More than 300 EGF-like sequences have been identified as domains of larger proteins (Campbell & Bork, 1993) and many of these probably have chain folds similar to those of EGF and TGFa. Medium-resolution NMR solution structures have been described for human EGF (Cooke et al, 1987;Hommel et al, 1992) and murine EGF (Montelione et al, 1986(Montelione et al, , 1987(Montelione et al, , 1992Kohda & Inagaki, 1992a, 1992b, and for several homologous proteins including hTGFa (Kline et al, 1990;Harvey et al, 1991;Moy et al, 1993) and the EGF-like domains from bovine coagulation factor X (Selander-Sunnerhagen et al, 1992; Energy refinement of mECF and hTGFa NMR structures Ullner et al, 1992), human factor 1X (Huang et al, 1991;Baron et al, 1992), human tissue-type plasminogen activator (Smith et al, 1994), and human urokinase-type plasminogen activator (Hansen et al, 1994). X-ray crystal structures of the EGF-like domains of human E-selectin (Graves et al, 1994;Weis, 1994) and human factor Xa (Padmanabhan et al, 1993) have also been determined recently.…”

“…The previously described structures of EGF and TGFa have either taken minimal account of conformational energy (Kline et al, 1990;Harvey et al, 1991;Hommel et al, 1992;Kohda & Inagaki, 1992a, 1992b or have attempted to refine NMR structures using a fairly complete potential energy function with simple conjugate-gradient minimization (Montelione et al, 1992;Moy et al, 1993). In this paper, we describe energy refinement of hTGFa and mEGF NMR structures by simulated annealing of molecular dynamics, using the CHAR" potential energy function (Brooks et al, 1983) and the CONGEN (Bruccoleri & Karplus, 1987) computer program.…”

Role of multidomain structure of urokinase in regulation of growth and remodeling of vessels

“…по своей структуре «ростовой» домен гомологи-чен эпидермальному фактору роста. похожей структурой обладают мышиный эпидермаль-ный фактор роста megf и трансформирую-щий фактор роста α tgf-α [10]. крингл-домен вовлечен в регуляцию миграции клеток под действием урокиназы [11], а также обеспечи-вает взаимодействие с гепарином через три последовательно расположенных аминокис-лотных остатка arg108-arg109-arg110 [12].…”