Deimination of Myelin Basic Protein. 1. Effect of Deimination of Arginyl Residues of Myelin Basic Protein on Its Structure and Susceptibility to Digestion by Cathepsin D†

Biochemistry ◽  
2000 ◽  
Vol 39 (18) ◽  
pp. 5374-5381 ◽  
Author(s):  
Laura B. Pritzker ◽  
Shashikant Joshi ◽  
Jessica J. Gowan ◽  
George Harauz ◽  
Mario A. Moscarello
Keyword(s):  
Myelin Basic Protein ◽  
Cathepsin D ◽  
Basic Protein ◽  
Arginyl Residues

N.M.R. studies on myelin basic protein. II. 1H N.M.R. studies of the protein and constituent peptides in aqueous solutions

1978 ◽  
Vol 31 (11) ◽  
pp. 2387 ◽  
Author(s):  
LAT Littlemore
Keyword(s):  
Chemical Shift ◽  
Myelin Basic Protein ◽  
Cathepsin D ◽  
Ring Current ◽  
Basic Protein ◽  
Tertiary Structure ◽  
Pulse Sequence ◽  
Chemical Shift Assignments ◽  
Peptide Fragment ◽  
Line Widths

1H N.M.R. spectra (270 MHz) of myelin basic protein (MBP) at pD 3.7 in D2O were obtained as a function of concentration and compared with computed spectra. Reduced line widths obtained for 0.5-mM samples and use of the convolution difference technique enabled detection of chemical shift heterogeneities for histidine, tyrosine, methionine, threonine, and isoleucine residues in the protein; this is indicative of secondary/tertiary structure. Chemical shift assignments were confirmed by the use of the Carr-Purcell A pulse sequence and selective decoupling as well as by correlation of the MBP spectrum with that of its constituent cathepsin D digest peptides. The methyl resonance from the unique methylated arginine-107 was found, and its chemical shift compared to that of NG-monomethyl-L-arginine and the methylated arginine peak in the peptide fragment, residues 90-170. The absence of ring- current effects on the methyl chemical shift precludes conformations of MBP in which the methylarginine interacts with the phenylalanine pair at residues 89 and 90.

Interactions of the 18.5-kDa isoform of myelin basic protein with Ca2+-calmodulin: in vitro studies using fluorescence microscopy and spectroscopy

2002 ◽  
Vol 80 (4) ◽  
pp. 395-406 ◽  
Author(s):  
David S Libich ◽  
George Harauz
Keyword(s):  
Fluorescence Microscopy ◽  
Myelin Basic Protein ◽  
Cathepsin D ◽  
Basic Protein ◽  
Dissociation Constants ◽  
Kinase Substrate ◽  
Trp Fluorescence ◽  
Binding Peptides ◽  
Carboxyl Terminal

The interactions of the 18.5-kDa isoform of myelin basic protein (MBP) with calmodulin (CaM) in vitro have been investigated using fluorescence microscopy and spectroscopy. Two forms of MBP were used: the natural bovine C1 charge isomer (bMBP/C1) and a hexahistidine-tagged recombinant murine product (rmMBP), with only minor differences in behaviour being observed. Fragments of each protein generated by digestion with cathepsin D (EC 3.4.23.5) were also evaluated. Using fluorescence microscopy, it was shown that MBP and CaM interacted in the presence of Ca2+ under a variety of conditions, including high urea and salt concentrations, indicating that the interaction was specific and not merely electrostatic in nature. Using cathepsin D digestion fragments of MBP, it was further shown that the carboxyl-terminal domain of MBP interacted with Ca2+-CaM, consistent with our theoretical prediction. Spectroscopy of the intrinsic fluorescence of the sole Trp residue of MBP showed that binding was cooperative in nature. The dissociation constants for formation of a 1:1 MBP-Ca2+-CaM complex were determined to be 2.1 ± 0.1 and 2.0 ± 0.2 μM for bMBP/C1 and rmMBP, respectively. Fluorescence spectroscopy using cathepsin D digestion fragments indicated also that the carboxyl-terminal region of each protein interacted with Ca2+-CaM, with dissociation constants of 1.8 ± 0.2 and 2.8 ± 0.9 μM for the bMBP/C1 and rmMBP fragments, respectively. These values show a roughly 1000-fold lower affinity of MBP for CaM than other CaM-binding peptides, such as myristoylated alanine-rich C-kinase substrate, that are involved in signal transduction. Key words: myelin basic protein, Ca2+-calmodulin, intrinsic Trp fluorescence, MARCKS, cathepsin D.

Acidic lipids enhance cathepsin D cleavage of the myelin basic protein

1986 ◽  
Vol 15 (2) ◽  
pp. 137-145 ◽  
Author(s):  
K. R. Williams ◽  
N. D. Williams ◽  
W. Konigsberg ◽  
R. K. Yu
Keyword(s):  
Myelin Basic Protein ◽  
Cathepsin D ◽  
Basic Protein ◽  
Acidic Lipids
Sign in / Sign up

Export Citation Format

Share Document