Pleckstrin is the major target of protein kinase C (PKC) in blood platelets. Its phosphorylation triggers responses that ultimately lead to platelet activation and blood clot formation. Pleckstrin consists of three domains: a pleckstrin homology (PH) domain at both termini and a central DEP (Dishevelled, Egl-1, Pleckstrin) domain. Here, we report the solution nuclear magnetic resonance (NMR) structure of the C-terminal PH domain (C-PH) of human pleckstrin-1. We show that this PH domain binds phosphatidylinositol-3,4-bisphosphate (PtdIns(3,4)P2) with high specificity in protein lipid overlay assays. Using NMR titration experiments and mutational analysis, residues involved in binding to PtdIns(3,4)P2 are identified. The binding site is formed by a patch of basic residues from the beta1 and beta2 strands and the beta1-beta2 loop. Since PtdIns(3,4)P2 is an important signaling molecule in platelets, our data suggest a C-PH dependent regulation of pleckstrin function in response to PtdIns(3,4)P2.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.str.2004.11.012DOI Listing

Publication Analysis

Top Keywords

c-terminal domain
8
pleckstrin
6
domain
5
structure phosphatidylinositol-34-bisphosphate
4
phosphatidylinositol-34-bisphosphate binding
4
binding c-terminal
4
domain human
4
human pleckstrin
4
pleckstrin pleckstrin
4
pleckstrin major
4

Similar Publications

The Orange Carotenoid Protein (OCP) is a unique water-soluble photoactive protein that plays a critical role in regulating the balance between light harvesting and photoprotective responses in cyanobacteria. The challenge in understanding OCP´s photoactivation mechanism stems from the heterogeneity of the initial configurations of its embedded ketocarotenoid, which in the dark-adapted state can form up to two hydrogen bonds to critical amino acids in the protein's C-terminal domain, and the extremely low quantum yield of primary photoproduct formation. While a series of experiments involving point mutations within these contacts helped us to identify these challenges, they did not resolve them.

View Article and Find Full Text PDF

Cryo-EM structure of human TUT1:U6 snRNA complex.

Nucleic Acids Res

January 2025

Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.

U6 snRNA (small nuclear ribonucleic acid) is a ribozyme that catalyzes pre-messenger RNA (pre-mRNA) splicing and undergoes epitranscriptomic modifications. After transcription, the 3'-end of U6 snRNA is oligo-uridylylated by the multi-domain terminal uridylyltransferase (TUTase), TUT1. The 3'- oligo-uridylylated tail of U6 snRNA is crucial for U4/U6 di-snRNP (small nuclear ribonucleoprotein) formation and pre-mRNA splicing.

View Article and Find Full Text PDF

Discovery of PRMT5 N-Terminal TIM Barrel Ligands from Machine-Learning-Based Virtual Screening.

ACS Omega

January 2025

Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States.

Protein arginine methyltransferase 5 (PRMT5), which symmetrically dimethylates cytosolic and nuclear proteins, has been demonstrated as an important cancer therapeutic target. In recent years, many advanced achievements in PRMT5 inhibitor development have been made. Most PRMT5 inhibitors in the clinical trial focus on targeting the C-terminal catalytic domain, whereas developing small molecules to interrupt the PRMT5/pICLn (methylosome subunit) protein-protein interface is also of great importance for inhibiting PRMT5.

View Article and Find Full Text PDF

Sevenless, the Drosophila homologue of ROS1 (University of Rochester Sarcoma) (herein, dROS1) is a receptor tyrosine kinase (RTK) essential for the differentiation of Drosophila R7 photoreceptor cells. Activation of dROS1 is mediated by binding to the extracellular region (ECR) of the GPCR (G protein coupled receptor) BOSS (Bride Of Sevenless) on adjacent cells. Activation of dROS1 by BOSS leads to subsequent downstream signaling pathways including SOS (Son of Sevenless).

View Article and Find Full Text PDF

Treponema denticola major surface protein (Msp): a key player in periodontal pathogenicity and immune evasion.

Arch Microbiol

January 2025

Department of Stomatology, The Second Affiliated Hospital, Hengyang Medical College, University of South China, Hengyang, 421001, Hunan, China.

Treponema denticola, a bacterium that forms a "red complex" with Porphyromonas gingivalis and Tannerella forsythia, is associated with periodontitis, pulpitis, and other oral infections. The major surface protein (Msp) is a surface glycoprotein with a relatively well-established overall domain structure (N-terminal, central and C-terminal regions) and a controversial tertiary structure. As one of the key virulence factors of T.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!