Crystallization and Structure Determination of Bovine Profilin at 2·0 Å Resolution

Cedergren-Zeppezauer, Eila; Goonesekere, Nalin C. W.; Rozycki, Michael D.; Myslik, James C.; Dauter, Zbigniew; Lindberg, Uno; Schutt, Clarence E.

doi:10.1006/jmbi.1994.1461

Cited by 79 publications

(83 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Using photoactivatable homologs of PI (4, 5)P 2 , Chaudhary et al (1998) subsequently hypothesized that the carboxy terminal basic residues in human profilin-I is involved in contacting the negative head groups of PI(4, 5)P 2 . A competition between poly-L-proline and PI (4, 5)P 2 for binding to profilin (Lambrechts et al 1997) has been observed, which is consistent with the proposal that the carboxy terminus of profilin is involved in PI(4, 5)P 2 binding (Cedergren-Zeppezauer et al 1994). Based on a comparison of the crystal structure of the two Acanthamoeba profilin isoforms, it has been proposed that a surface Human Profilin-I Human Profilin -II Fig.…”

Section: Profilin and Phosphatidylinositol 4 5-bisphosphate [Pi(4 5supporting

confidence: 89%

Structure and functions of profilins

Krishnan

Moens

2009

Biophys Rev

View full text Add to dashboard Cite

Profilins are small actin-binding proteins found in eukaryotes and certain viruses that are involved in cell development, cytokinesis, membrane trafficking, and cell motility. Originally identified as an actin sequestering/ binding protein, profilin has been involved in actin polymerization dynamics. It catalyzes the exchange of ADP/ATP in actin and increases the rate of polymerization. Profilins also interact with polyphosphoinositides (PPI) and proline-rich domains containing proteins. Through its interaction with PPIs, profilin has been linked to signaling pathways between the cell membrane and the cytoskeleton, while its role in membrane trafficking has been associated with its interaction with proline-rich domain-containing proteins. Depending on the organism, profilin is present in a various number of isoforms. Four isoforms of profilin have been reported in higher organisms, while only one or two isoforms are expressed in single-cell organisms. The affinity of these isoforms for their ligands varies between isoforms and should therefore modulate their functions. However, the significance and the functions of the different isoforms are not yet fully understood. The structures of many profilin isoforms have been solved both in the presence and the absence of actin and poly-L-proline. These structural studies will greatly improve our understanding of the differences and similarities between the different profilins. Structural stability studies of different profilins are also shedding some light on our understanding of the profilin/ligand interactions. Profilin is a multifaceted protein for which a dramatic increase in potential functions has been found in recent years; as such, it has been implicated in a variety of physiological and pathological processes.

show abstract

Section: Profilin and Phosphatidylinositol 4 5-bisphosphate [Pi(4 5supporting

confidence: 89%

Structure and functions of profilins

Krishnan

Moens

2009

Biophys Rev

View full text Add to dashboard Cite

show abstract

“…3, C and D), both are consequently also similar to CitA and PhoQ, but the dual arrangement of two PDC subdomains is unique. Shortly after our structure determinations, it was shown that the sensor domain of Vibrio harveyi LuxQ also displays a similar quasi-tandem subdomain topology (30,31).…”

Section: Resultsmentioning

confidence: 93%

Crystal Structures of C4-Dicarboxylate Ligand Complexes with Sensor Domains of Histidine Kinases DcuS and DctB

Cheung

Hendrickson

2008

Journal of Biological Chemistry

101

161

View full text Add to dashboard Cite

Two-component signaling systems allow bacteria to adapt to changing environments. Typically, a chemical or other stimulus is detected by the periplasmic sensor domain of a transmembrane histidine kinase sensor, which in turn relays a signal through a phosphotransfer cascade to the cognate cytoplasmic response regulator. Such systems lead ultimately to changes in gene expression or cell motility. Mechanisms of ligand binding and signal transduction through the cell membrane in histidine kinases are not fully understood. In an effort to further understand such processes, we have solved the crystal structures of the periplasmic sensor domains of Escherichia coli DcuS and of Vibrio cholerae DctB in complex with the respective cognate ligands, malate and succinate. Both proteins are involved in the regulation of the transport and metabolism of C 4 -dicarboxylates, but they are not highly related by sequence similarity. Our work reveals that despite disparate sizes, both structures contain a similar characteristic ␣/␤ PDC (PhoQ-DcuS-CitA) sensor-domain fold and display similar modes of ligand binding, suggesting similar mechanisms of function.The ability of bacteria to monitor and adapt to their environment is crucial to their survival, and two-component signal transduction systems mediate most of these adaptive responses. One component is a histidine kinase sensor, most commonly part of a homodimeric transmembrane sensor protein, and the second component is a cytoplasmic response regulator. The two components interact in tandem through a phosphotransfer cascade (1-4). A typical transmembrane sensor protein contains a periplasmic sensor domain and a cytoplasmic histidine kinase domain. Upon binding of a ligand to the periplasmic sensor domain, this signal is transduced across the membrane to the cytoplasmic domain where an ATP-dependent autophosphorylation of a conserved histidine residue occurs (1). The phosphate is subsequently transferred to a conserved aspartate residue in the response regulator protein by an auto-catalyzed reaction (2), ultimately leading to adaptive modulation of gene expression. In some circumstances, sensor stimulation leads to dephosphorylation. Within the large family of protein histidine kinases, the sequence of the sensor domain is considered to be modular, whereas that of the histidine kinase domain is more conserved. Over the past decade, especially with the determination of numerous bacterial genome sequences, hundreds of new histidine kinase proteins have been identified but remain unstudied.The DcuS-DcuR two component system is involved in the regulation of the anaerobic fumarate respiratory pathway in Escherichia coli (5, 6). The sensor kinase DcuS is a member of the CitA family of histidine kinases, and it responds to C 4 -dicarboxylates such as fumarate, succinate, malate, and tartrate (5, 7). Upon detection of its cognate ligand, the DcuS-DcuR system up-regulates the synthesis of both fumarate reductase (frdABCD) and also the anaerobic fumarate-succinate antiporter DcuB. DcuS is p...

show abstract

“…Next we sought to determine whether these moderate structural changes between PFN1 WT and M114T mapped to regions involved in PFN1 function, namely to residues that make contact with actin (24-31) or poly-L-proline (21,22,24,32,33). The ternary complex comprised of PFN1 WT, actin, and the poly-Lproline peptide derived from vasodilator-stimulated phosphoprotein (VASP) (21) (PDB ID code 2PAV) is shown in Fig.…”

Section: Als-linked Mutations Induce a Misfolded Conformation Within mentioning

confidence: 99%

Structural basis for mutation-induced destabilization of profilin 1 in ALS

Boopathy

Silvas

Tischbein

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

110

View full text Add to dashboard Cite

Mutations in profilin 1 (PFN1) are associated with amyotrophic lateral sclerosis (ALS); however, the pathological mechanism of PFN1 in this fatal disease is unknown. We demonstrate that ALS-linked mutations severely destabilize the native conformation of PFN1 in vitro and cause accelerated turnover of the PFN1 protein in cells. This mutationinduced destabilization can account for the high propensity of ALSlinked variants to aggregate and also provides rationale for their reported loss-of-function phenotypes in cell-based assays. The source of this destabilization is illuminated by the X-ray crystal structures of several PFN1 proteins, revealing an expanded cavity near the protein core of the destabilized M114T variant. In contrast, the E117G mutation only modestly perturbs the structure and stability of PFN1, an observation that reconciles the occurrence of this mutation in the control population. These findings suggest that a destabilized form of PFN1 underlies PFN1-mediated ALS pathogenesis.amyotrophic lateral sclerosis | profilin 1 | protein stability | X-ray crystallography | protein misfolding M utations in the profilin 1 gene (PFN1) were recently associated with both familial and sporadic forms of amyotrophic lateral sclerosis (ALS) (1, 2), an incurable and fatal neurodegenerative disease that primarily targets motor neurons (3). The etiology of sporadic ALS is poorly understood, whereas familial ALS is caused by inheritable genetic defects in defined genes such as PFN1 (3). PFN1 is a 15-kDa protein that is best known for its role in actin dynamics in the context of endocytosis, membrane trafficking, cell motility, and neuronal growth and differentiation (4). In addition to binding monomeric or G-actin, PFN1 also binds to a host of different proteins through their poly-L-proline motifs and to lipids such as phosphatidylinositol 4,5-bisphosphate (4, 5). However, little is known about the mechanism(s) associated with PFN1-mediated ALS pathogenesis. The observation that most ALS-linked PFN1 variants are highly prone to aggregation in mammalian cultured cells suggests that diseasecausing mutations induce an altered, or misfolded, conformation within PFN1 (2). Protein misfolding is a hallmark feature of most neurodegenerative diseases, including ALS (3), and can contribute to disease through both gain-of-toxic-function and loss-of-normalfunction mechanisms (6). Although mutations in PFN1 cause ALS through a dominant inheritance mode (2), there is some evidence supporting a loss-of-function mechanism for mutant PFN1. For example, ALS-linked mutations were shown to abrogate the binding of PFN1 to actin (2) and to impair the incorporation of PFN1 into cytoplasmic stress granules during arsenite-induced stress (7) in cultured cells. Moreover, ectopic expression of these variants in murine motor neurons led to a reduction in both axon outgrowth and growth cone size, consistent with a loss of function through a dominant-negative mechanism (2).Although ALS-linked mutations were shown to induce PFN1 aggregation, the ef...

show abstract

Crystallization and Structure Determination of Bovine Profilin at 2·0 Å Resolution

Cited by 79 publications

References 0 publications

Structure and functions of profilins

Structure and functions of profilins

Crystal Structures of C4-Dicarboxylate Ligand Complexes with Sensor Domains of Histidine Kinases DcuS and DctB

Structural basis for mutation-induced destabilization of profilin 1 in ALS

Contact Info

Product

Resources

About