Protection of one of the two reactive thiol groups in F-actin by ATP and phalloidin.

  title={Protection of one of the two reactive thiol groups in F-actin by ATP and phalloidin.},
  author={H. Blackholm and H. Faulstich},
  journal={Biochemical and biophysical research communications},
  volume={103 1},
  • H. Blackholm, H. Faulstich
  • Published 16 November 1981
  • Chemistry, Medicine
  • Biochemical and biophysical research communications
In F-actin, [A(SH)5]n, prepared from rabbit skeletal muscle, two thiol groups react with 2,4-dinitrophenyl-glutathionyl-disulfide, DNPSSG, to form [A(SH)3(SSG)2]n. One of the two thiol groups reacts fast, (20 min), while the reaction of the second is slow (200 min). The fast reacting group has been identified as cysteine-373. In the presence of approximately one equivalent of ATP, only one of the thiol groups is reactive. The reaction product is [A(SH)4SSG]n. In comparison, the shielding… 
Nucleotide in monomeric actin regulates the reactivity of the thiol groups.
It was shown that the thiol-shielding activity and the protective capacity of a nucleotide are interrelated with its binding capability to monomeric actin.
Disulfide cross-linking of caldesmon to actin.
It is possible to maximally cross-link one caldesmon molecule/every three actin monomers, in the absence or presence of tropomyosin, clearly ruling out an elongated, end-to-end alignment of caldESmon on the actin filament in vitro, and raising the possibility that the N-terminal part of c Caldesmon projects out from the filament.
The molecular mechanism of interaction of Et3Pb+ with tubulin
After complexation of the two thiol groups, tubulin in vitro had lost its capability for microtubule assembly and polymerized tubulin disassembled on addition of the lead compound.
The effect of glutaraldehyde and phalloidin on the conformation of F-actin.
Recent data allow the assertion that conformational changes in F-actin regulate actin-myosin interaction in muscle fibre (Adelstein and Eisenberg 1980; Lednev 1980; Yanagida and Oosawa 1980;
The detection of denervation-induced structural changes in actin by phalloidin.
It has been shown earlier, that actin from denervated muscles is not readily polymerized and does not actively combine with heavy meromyosin, so it was of interest to use phalloidin which binds specifically to F-actin affects these bonds to study changes in the actin structure occurring during denervation.
The effect of caldesmon on actin-myosin interaction in skeletal muscle fibers.
The results suggest that the restraint for the alteration of actin structure and dynamics upon binding of myosin heads and/or tropomyosin evoked by caldesmon can be related to its inhibitory effect on actin-myosin interaction.


The interaction of phalloidin, some of its derivatives, and of other cyclic peptides with muscle actin as studied by viscosimetry
The interaction of G-actin with phalloidin (Ia), phall acidin, phallacidin, desmethylphalloin (Ic), its toxic and non-Toxic sulfoxides (Id, Ie), the non-toxic derivatives desthiophalloidsin (If) and secophalloid in (Ig) as well as a-amanitin and a soluble preparation of antamanide were studied.
Site of action of sulfhydryl spin labels with skeletal muscle actin
To help interpret the electron spin resonance (esr) spectra of spin-labeled actin, the positions of attachment of the spin labels, N-(1-oxyl-2,2,6,6-tetramethyl-4-piperidinyl) maleimide and
The dissociation of the phalloidin-actin complex.
The dissociation of the toxin and the breakdown of the filaments together with a concomitant release of Ca and ADP are interdependent events.
Synthesis of a protein-reactive ATP analog and its application for the affinity labeling of rabbit-muscle actin.
The synthesis of a protein-reactive ATP analog, S-dinitrophenyl-6-mercaptopurine riboside 5′-triphosphate, started from isopropylidated 6-mer captureurine and could not be depolymerized by ATP solutions at low ionic strength.
The selective blocking of the polymerization reaction of striated muscle actin leading to a derivative suitable for crystallization. Modification of Tyr-53 by 5-diazonium-(1H)tetrazole.
The polymerization reaction of rabbit muscle actin was completely inhibited by reaction of one amino acid side chain per protein monomer with 5-diazonium-(1H)[14C]tetrazole. A tryptic peptide
Effect of cytochalasin B on formation and properties of muscle F-actin.
It is suggested that the stability of actin filaments is reduced by cytochalasin B, which reduced the viscosity of F-actin and caused the appearance of ATP hydrolysis by F- actin.
Phalloidin counteracts the inhibitory effect of actin on deoxyribonuclease I
The toadstool poison phalloidin accelerates the polymerization of actin and stabilizes the microfilaments against 0.6 M KI, as well as against depolymerization under different conditions, e.g. by ATP, ultrasonic vibration or by cytochalasin B.