Polypeptide chain fold of human transforming growth factor .alpha. analogous to those of mouse and human epidermal growth factors as studied by two-dimensional proton NMR
Abstract
The 1H NMR spectrum of human transforming growth factor alpha (TGF-alpha) was analyzed almost completely by the sequential assignment method using two-dimensional NMR techniques. On the basis of the nearly complete sequence-specific resonance assignment, secondary and tertiary structures of human TGF-alpha in solution (pH 4.9, 28 degrees C) were determined to satisfy the upper limits of proton-proton distances derived from nuclear Overhauser effect experiments. Although human TGF-alpha and mouse epidermal growth factor (EGF) share 27% homology in amino acid sequence, the backbone chain folds in the two growth factors are quite similar. The structure and function of TGF-alpha is well characterized by the "mitten model" previously proposed for mouse EGF. The gross shape of the TGF-alpha molecule resembles a mitten. TGF-alpha interacts with the receptor as a mitten would grasp an object. However, there is an appreciable structural difference between the two growth factors in the back of the mitten that is formed by the N-terminal polypeptide segment. This is consistent with the evidence that the backs of these molecules are not involved in the receptor binding.
Related Papers
- → Basic Types of Correlation between Text and Icon, between Verbal and Visual Icons(2006)5 cited
- → The Effect of Icon Prediction on College Students' Recall of Icon Codes(2000)
- Susquehanna Chorale Spring Concert "Roots and Wings"(2017)
- → Icon «The Judgment of the Jews over Christ» of the First Half of the XIX Century(2020)
- → A new discovery. The icon of «St. Sergius, Nikon and Savva»(2022)