14-3-3 proteins are promising LRRK2 interactors

2010 ◽  
Vol 430 (3) ◽  
pp. e5-e6 ◽  
Author(s):  
Iakov N. Rudenko ◽  
Mark R. Cookson

Mutations in LRRK2 (leucine-rich repeat kinase 2) are the most common cause of familial PD (Parkinson’s disease). Mutations that cause PD are found in either the GTPase or kinase domains of LRRK2 or an intervening sequence called the COR [C-terminus of ROC (Ras of complex proteins)] domain. As well as the two catalytic domains, LRRK2 possesses several protein–protein interaction domains, but their function and the proteins with which they interact are poorly understood. In this issue of the Biochemical Journal, Nichols et al. study the interaction of the N-terminal region of LRRK2 with 14-3-3 proteins, regulatory proteins that often bind to phosphorylated regions of components of cell signalling pathways. Using a combination of techniques, Nichols et al. have identified two residues (Ser910 and Ser935) that are critically responsible for 14-3-3 binding. The interaction of LRRK2 with 14-3-3 proteins can prevent dephosphorylation of Ser910/Ser935 and stabilize LRRK2 structure, perhaps by influencing the dimerization of LRRK2. The ability to interact with 14-3-3 correlates with the pattern of intracellular LRRK2 distribution. Collectively, these new results identify a potentially important regulatory mechanism of this complex protein and might provide ways to think about therapeutic opportunities for PD.

2008 ◽  
Vol 414 (2) ◽  
pp. 221-229 ◽  
Author(s):  
Xinjiang Wang ◽  
Yuji Shi ◽  
Junru Wang ◽  
Guochang Huang ◽  
Xuejun Jiang

PTEN (phosphatase and tensin homologue deleted on chromosome 10), a potent tumour suppressor and multifunctional signalling protein, is under intricate regulation. In the present study, we have investigated the mechanism and regulation of PTEN ubiquitination catalysed by NEDD4-1 (neural-precursor-cell-expressed, developmentally down-regulated 4-1), a ubiquitin ligase for PTEN we identified recently. Using the reconstituted assay and cellular analysis, we demonstrated that NEDD4-1-mediated PTEN ubiquitination depends on its intact HECT (homologous to E6-associated protein C-terminus) domain. Instead of using its WW domains (protein–protein interaction domains containing two conserved tryptophan residues) as a protein interaction module, NEDD4-1 interacts with PTEN through its N-terminal region containing a C2 domain as well as the HECT domain. Strikingly, we found that a C-terminal truncated PTEN fragment binds to NEDD4-1 with higher affinity than the full-length PTEN, suggesting an intrinsic inhibitory effect of the PTEN C-terminus on PTEN–NEDD4-1 interaction. Moreover, the C-terminal truncated PTEN is more sensitive to NEDD4-1-mediated ubiquitination and degradation. Therefore the present study reveals that the C-terminus of PTEN plays a critical role in stabilizing PTEN via antagonizing NEDD4-1-induced PTEN protein decay; conversely, truncation of the PTEN C-terminus results in rapid NEDD4-1-mediated PTEN degradation, a possible mechanism accounting for attenuation of PTEN function by certain PTEN mutations in human cancers.


2008 ◽  
Vol 415 (1) ◽  
pp. 155-163 ◽  
Author(s):  
M. Christine Bruce ◽  
Voula Kanelis ◽  
Fatemeh Fouladkou ◽  
Anne Debonneville ◽  
Olivier Staub ◽  
...  

Ubiquitin ligases play a pivotal role in substrate recognition and ubiquitin transfer, yet little is known about the regulation of their catalytic activity. Nedd4 (neural-precursor-cell-expressed, developmentally down-regulated 4)-2 is an E3 ubiquitin ligase composed of a C2 domain, four WW domains (protein–protein interaction domains containing two conserved tryptophan residues) that bind PY motifs (L/PPXY) and a ubiquitin ligase HECT (homologous with E6-associated protein C-terminus) domain. In the present paper we show that the WW domains of Nedd4-2 bind (weakly) to a PY motif (LPXY) located within its own HECT domain and inhibit auto-ubiquitination. Pulse–chase experiments demonstrated that mutation of the HECT PY-motif decreases the stability of Nedd4-2, suggesting that it is involved in stabilization of this E3 ligase. Interestingly, the HECT PY-motif mutation does not affect ubiquitination or down-regulation of a known Nedd4-2 substrate, ENaC (epithelial sodium channel). ENaC ubiquitination, in turn, appears to promote Nedd4-2 self-ubiquitination. These results support a model in which the inter- or intra-molecular WW-domain–HECT PY-motif interaction stabilizes Nedd4-2 by preventing self-ubiquitination. Substrate binding disrupts this interaction, allowing self-ubiquitination of Nedd4-2 and subsequent degradation, resulting in down-regulation of Nedd4-2 once it has ubiquitinated its target. These findings also point to a novel mechanism employed by a ubiquitin ligase to regulate itself differentially compared with substrate ubiquitination and stability.


2020 ◽  
Vol 477 (7) ◽  
pp. 1219-1225 ◽  
Author(s):  
Nikolai N. Sluchanko

Many major protein–protein interaction networks are maintained by ‘hub’ proteins with multiple binding partners, where interactions are often facilitated by intrinsically disordered protein regions that undergo post-translational modifications, such as phosphorylation. Phosphorylation can directly affect protein function and control recognition by proteins that ‘read’ the phosphorylation code, re-wiring the interactome. The eukaryotic 14-3-3 proteins recognizing multiple phosphoproteins nicely exemplify these concepts. Although recent studies established the biochemical and structural basis for the interaction of the 14-3-3 dimers with several phosphorylated clients, understanding their assembly with partners phosphorylated at multiple sites represents a challenge. Suboptimal sequence context around the phosphorylated residue may reduce binding affinity, resulting in quantitative differences for distinct phosphorylation sites, making hierarchy and priority in their binding rather uncertain. Recently, Stevers et al. [Biochemical Journal (2017) 474: 1273–1287] undertook a remarkable attempt to untangle the mechanism of 14-3-3 dimer binding to leucine-rich repeat kinase 2 (LRRK2) that contains multiple candidate 14-3-3-binding sites and is mutated in Parkinson's disease. By using the protein-peptide binding approach, the authors systematically analyzed affinities for a set of LRRK2 phosphopeptides, alone or in combination, to a 14-3-3 protein and determined crystal structures for 14-3-3 complexes with selected phosphopeptides. This study addresses a long-standing question in the 14-3-3 biology, unearthing a range of important details that are relevant for understanding binding mechanisms of other polyvalent proteins.


2020 ◽  
Vol 27 (11) ◽  
pp. 1068-1081
Author(s):  
Xi Liu ◽  
Dongwu Liu ◽  
Yangyang Shen ◽  
Mujie Huang ◽  
Lili Gao ◽  
...  

Matrix Metalloproteinases (MMPs) belong to a family of metal-dependent endopeptidases which contain a series of conserved pro-peptide domains and catalytic domains. MMPs have been widely found in plants, animals, and microorganisms. MMPs are involved in regulating numerous physiological processes, pathological processes, and immune responses. In addition, MMPs play a key role in disease occurrence, including tumors, cardiovascular diseases, and other diseases. Compared with invertebrate MMPs, vertebrate MMPs have diverse subtypes and complex functions. Therefore, it is difficult to study the function of MMPs in vertebrates. However, it is relatively easy to study invertebrate MMPs because there are fewer subtypes of MMPs in invertebrates. In the present review, the structure and function of MMPs in invertebrates were summarized, which will provide a theoretical basis for investigating the regulatory mechanism of MMPs in invertebrates.


2021 ◽  
Vol 11 (5) ◽  
pp. 578
Author(s):  
Oge Gozutok ◽  
Benjamin Ryan Helmold ◽  
P. Hande Ozdinler

Hereditary spastic paraplegia (HSP) and primary lateral sclerosis (PLS) are rare motor neuron diseases, which affect mostly the upper motor neurons (UMNs) in patients. The UMNs display early vulnerability and progressive degeneration, while other cortical neurons mostly remain functional. Identification of numerous mutations either directly linked or associated with HSP and PLS begins to reveal the genetic component of UMN diseases. Since each of these mutations are identified on genes that code for a protein, and because cellular functions mostly depend on protein-protein interactions, we hypothesized that the mutations detected in patients and the alterations in protein interaction domains would hold the key to unravel the underlying causes of their vulnerability. In an effort to bring a mechanistic insight, we utilized computational analyses to identify interaction partners of proteins and developed the protein-protein interaction landscape with respect to HSP and PLS. Protein-protein interaction domains, upstream regulators and canonical pathways begin to highlight key cellular events. Here we report that proteins involved in maintaining lipid homeostasis and cytoarchitectural dynamics and their interactions are of great importance for UMN health and stability. Their perturbation may result in neuronal vulnerability, and thus maintaining their balance could offer therapeutic interventions.


2012 ◽  
Vol 367 (1602) ◽  
pp. 2540-2555 ◽  
Author(s):  
Jing Jin ◽  
Tony Pawson

Phosphorylation sites are formed by protein kinases (‘writers’), frequently exert their effects following recognition by phospho-binding proteins (‘readers’) and are removed by protein phosphatases (‘erasers’). This writer–reader–eraser toolkit allows phosphorylation events to control a broad range of regulatory processes, and has been pivotal in the evolution of new functions required for the development of multi-cellular animals. The proteins that comprise this system of protein kinases, phospho-binding targets and phosphatases are typically modular in organization, in the sense that they are composed of multiple globular domains and smaller peptide motifs with binding or catalytic properties. The linkage of these binding and catalytic modules in new ways through genetic recombination, and the selection of particular domain combinations, has promoted the evolution of novel, biologically useful processes. Conversely, the joining of domains in aberrant combinations can subvert cell signalling and be causative in diseases such as cancer. Major inventions such as phosphotyrosine (pTyr)-mediated signalling that flourished in the first multi-cellular animals and their immediate predecessors resulted from stepwise evolutionary progression. This involved changes in the binding properties of interaction domains such as SH2 and their linkage to new domain types, and alterations in the catalytic specificities of kinases and phosphatases. This review will focus on the modular aspects of signalling networks and the mechanism by which they may have evolved.


Microbiology ◽  
2014 ◽  
Vol 160 (12) ◽  
pp. 2745-2754 ◽  
Author(s):  
Alistair J. Standish ◽  
Jonathan J. Whittall ◽  
Renato Morona

Tyrosine phosphorylation has long been recognized as a crucial post-translational regulatory mechanism in eukaryotes. However, only in the past decade has recognition been given to the crucial importance of bacterial tyrosine phosphorylation as an important regulatory feature of pathogenesis. This study describes the effect of tyrosine phosphorylation on the activity of a major virulence factor of the pneumococcus, the autolysin LytA, and a possible connection to the Streptococcus pneumoniae capsule synthesis regulatory proteins (CpsB, CpsC and CpsD). We show that in vitro pneumococcal tyrosine kinase, CpsD, and the protein tyrosine phosphatase, CpsB, act to phosphorylate and dephosphorylate LytA. Furthermore, this modulates LytA function in vitro with phosphorylated LytA binding more strongly to the choline analogue DEAE. A phospho-mimetic (Y264E) mutation of the LytA phosphorylation site displayed similar phenotypes as well as an enhanced dimerization capacity. Similarly, tyrosine phosphorylation increased LytA amidase activity, as evidenced by a turbidometric amidase activity assay. Similarly, when the phospho-mimetic mutation was introduced in the chromosomal lytA of S. pneumoniae, autolysis occurred earlier and at an enhanced rate. This study thus describes, to our knowledge, the first functional regulatory effect of tyrosine phosphorylation on a non-capsule-related protein in the pneumococcus, and suggests a link between the regulation of LytA-dependent autolysis of the cell and the biosynthesis of capsular polysaccharide.


2018 ◽  
Vol 19 (7) ◽  
pp. 2131 ◽  
Author(s):  
Lili Niu ◽  
Biying Dong ◽  
Zhihua Song ◽  
Dong Meng ◽  
Yujie Fu

In the CIPK family, the CBL-interacting protein kinases have shown crucial roles in hormone signaling transduction, and response to abiotic stress in plant developmental processes. The CIPK family is characterized by conserved NAF/FISL (Asn-Ala-Phe) and PPI (protein-phosphatase interaction) domains in the C-terminus. However, little data has been reported about the CIPK family in apple. A total of 34 MdCIPK genes were identified from the apple genome in this study and were later divided into two groups according to the CIPK domains, characterized by gene structure and chromosomal distribution, and then mapped onto 17 chromosomes. All MdCIPK genes were expressed in the four apple tissues (leaf, root, flower, and fruit). In addition, the MdCIPK gene expression profile showed that five members among them revealed enhanced expression during the pollen tube growth stages. The MdCIPK4 was the most expressive during the entire fruit development stages. Under stress conditions 21 MdCIPK genes transcript levels were up-regulated in response to fungal and salt treatments. This suggested the possible features of these genes’ response to stresses in apples. Our findings provide a new insight about the roles of CIPK genes in apples, which could contribute to the cloning and functional analysis of CIPK genes in the future.


2010 ◽  
Vol 433 (2) ◽  
pp. e1-e2 ◽  
Author(s):  
Zachary A. Knight

More than 20 protein kinases are directly activated by 3-phosphoinositide-dependent kinase 1 (PDK1), which is a central component of the pathways that regulate cell growth, proliferation and survival. Despite the importance of PDK1 in cell signalling, highly selective PDK1 inhibitors have not been described. In this issue of the Biochemical Journal, Dario Alessi's group and their collaborators at GlaxoSmithKline report GSK2334470, a potent and selective PDK1 inhibitor. They show that this compound blocks the phosphorylation of known PDK1 substrates, but surprisingly find that the potency and kinetics of inhibition vary for different PDK1 targets. This substrate-specific inhibition has implications for the development of PDK1 inhibitors as drugs.


2008 ◽  
Vol 18 (9) ◽  
pp. 1500-1508 ◽  
Author(s):  
K. Xia ◽  
Z. Fu ◽  
L. Hou ◽  
J.-D. J. Han

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