Identification of Two Sites in Gelsolin with Different Sensitivities to Adenine Nucleotides

Laham, Lorraine E.; Way, Michael; Yin, Helen L.; Janmey, Paul A.

doi:10.1111/j.1432-1033.1995.001_c.x

Cited by 12 publications

(11 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reduced rate of severing observed in gelsolin lacking the disulfide is lost at saturating calcium concentrations (data not shown), similar to the lack of differences observed in the severing rates (Fig. 4), and monomer binding rates [24] of calcium insensitive Nterminal truncates. These results suggest that the disulfide bond in domain 2 of plasma gelsolin serves to facilitate communication between Ca 2+ binding sites in the C-terminus and active sites in the N-terminus.…”

Section: Discussionsupporting

confidence: 78%

“…However, there is no evidence to suggest that domain 2 of gelsolin binds Ca 2+ directly. Nterminal truncates of gelsolin containing domains 1-3 sever actin filaments and bind actin monomers [4,24] rapidly in the complete absence of divalent cations. I assayed N-terminal truncates containing domains 1-3 of recombinant and plasma gelsolin to determine whether the Ca 2+ insensitive rate of severing was altered by the presence or absence of the disulfide in domain 2.…”

Section: Severing By N-terminal Fragmentsmentioning

confidence: 99%

See 1 more Smart Citation

Functional consequences of disulfide bond formation in gelsolin

Allen¹

1997

FEBS Letters

View full text Add to dashboard Cite

Gelsolin is an actin monomer binding and filament severing protein synthesized in plasma and cytoplasmic forms differing by an N-terminal amino acid extension and a disulfide bond between Cys-188 and Cys-201. To determine whether this bond altered gelsolin regulation or function, oxidized and reduced plasma gelsolins were assayed for severing, monomer binding and nucleation activity at a variety of rate-limiting calcium concentrations. The results indícate that the disulfide bond in domain 2 of gelsolin influences the transmission of information from C-terminal regulatory sites to functional sites in the Nterminus.

show abstract

Section: Discussionsupporting

confidence: 78%

Section: Severing By N-terminal Fragmentsmentioning

confidence: 99%

Functional consequences of disulfide bond formation in gelsolin

Allen¹

1997

FEBS Letters

View full text Add to dashboard Cite

show abstract

“…Profilin, thymosin-␤4, vitamin D-binding protein, Arp2/3 complex, and WH2 domain proteins have higher affinity to ATP-actin. Other proteins, such as gelsolin and cofilin, bind predominantly to ADP-actin (52)(53)(54). However, the detailed nature of conformational rearrangements on actin underlying the ABP binding selectivity is unknown.…”

Section: Discussionmentioning

confidence: 99%

A Nucleotide State-sensing Region on Actin

Kudryashov

Grintsevich

Rubenstein

et al. 2010

Journal of Biological Chemistry

View full text Add to dashboard Cite

The nucleotide state of actin (ATP, ADP-P i , or ADP) is known to impact its interactions with other actin molecules upon polymerization as well as with multiple actin binding proteins both in the monomeric and filamentous states of actin. Recently, molecular dynamics simulations predicted that a sequence located at the interface of subdomains 1 and 3 (W-loop; residues 165-172) changes from an unstructured loop to a ␤-turn conformation upon ATP hydrolysis (Zheng, X., Diraviyam, K., and Sept, D. (2007) Biophys. J. 93, 1277-1283). This region participates directly in the binding to other subunits in F-actin as well as to cofilin, profilin, and WH2 domain proteins and, therefore, could contribute to the nucleotide sensitivity of these interactions. The present study demonstrates a reciprocal communication between the W-loop region and the nucleotide binding cleft on actin. Point mutagenesis of residues 167, 169, and 170 and their site-specific labeling significantly affect the nucleotide release from the cleft region, whereas the ATP/ADP switch alters the fluorescence of probes located in the W-loop. In the ADP-P i state, the W-loop adopts a conformation similar to that in the ATP state but different from the ADP state. Binding of latrunculin A to the nucleotide cleft favors the ATP-like conformation of the W-loop, whereas ADP-ribosylation of Arg-177 forces the W-loop into a conformation distinct from those in the ADP and ATP-states. Overall, our experimental data suggest that the W-loop of actin is a nucleotide sensor, which may contribute to the nucleotide state-dependent changes in F-actin and nucleotide state-modulated interactions of both G-and F-actin with actin-binding proteins.Actin, one of the most abundant and conserved eukaryotic proteins, is involved in a variety of cellular functions, from cell division and migration to intracellular transport and endo-and exocytosis. Under physiological conditions, monomeric actin (G-actin) 3 and filamentous actin (F-actin) are in a dynamic equilibrium, strongly favoring the latter. Very low basal ATPase activity of G-actin is amplified strongly upon its polymerization, and the release of inorganic P i in general follows the polymerization with some delay (2, 3). Consequently, under equilibrium conditions, a typical actin filament contains ATP protomers at the growing end followed by an ADP-P i -enriched region and then by an extended ADP region in the rest of the filament. The nature of the bound nucleotide influences the properties of G-and F-actin and controls their interactions with a number of actin-binding proteins (ABP), which play key regulatory and structural roles in the dynamics and maintenance of the actin cytoskeleton. Nucleotide-sensitive ABPs regulate nucleotide exchange rates and the polymerization of G-actin, the nucleation of new filaments, and disassembly of mature filaments. Thus, preferential binding of the Arp2/3 nucleating complex to ATP and ADP-P i F-actin, cofilin to ADP-F-actin, and profilin to ATP-G-actin leads to the acceleration of directe...

show abstract

“…17 In accordance, G4-G6 displays a preference for ADP-containing actin monomers while G1-G3 binds to ATP-and ADP-Gactin with comparable affinities. 18 Actin nucleotide exchange is diminished or abrogated in the 1:2 and 1:1 gelsolin:actin complexes, respectively. 19 Discovery of a strong interaction between gelsolin and ATP led to suggestions that ATP might be involved in some of the multiple functions of gelsolin.…”

Section: Introductionmentioning

confidence: 99%