Three-dimensional structures of H-ras p21 mutants: Molecular basis for their inability to function as signal switch molecules

Cell ◽  
1990 ◽  
Vol 62 (3) ◽  
pp. 539-548 ◽  
Author(s):  
Ute Krengel ◽  
Ilme Schlichting ◽  
Anna Scherer ◽  
Renate Schumann ◽  
Matthias Frech ◽  
...  
Keyword(s):  
Molecular Basis ◽  
Three Dimensional ◽  
Ras P21 ◽  
Signal Switch

scholarly journals The molecular basis of mouse sperm–zona pellucida binding: a still unresolved issue in developmental biology

Reproduction ◽  
2011 ◽  
Vol 142 (3) ◽  
pp. 377-381 ◽  
Author(s):  
Gary F Clark
Keyword(s):  
Zona Pellucida ◽  
Molecular Basis ◽  
Three Dimensional ◽  
Inhibitory Effect ◽  
Specific Model ◽  
Cell Stage ◽  
Sperm Binding ◽  
Potent Inhibitory Effect ◽  
Alternate Model ◽  
Sperm Plasma Membrane

During murine fertilization, sperm bind to the specialized extracellular matrix of the egg, known as the zona pellucida (ZP). This matrix is composed of three major glycoproteins designated ZP1, ZP2, and ZP3. Three models for sperm–ZP binding are now under consideration. The domain-specific model posits that adhesion relies primarily on interactions between N-glycans located within the C-terminal domain of ZP3 and a lectin-like egg-binding protein in the sperm plasma membrane. However, this model does not explain recent results obtained in studies with ZP2mut mice. In the supramolecular structure model, sperm bind to a three-dimensional zona matrix that depends on the cleavage status of ZP2. This paradigm does not explain the potent inhibitory effect of specific carbohydrate sequences or a C-terminal glycopeptide (gp55) derived from ZP3. Recently, O-glycans linked at Thr155 and Thr162 of ZP3 were implicated as potential ligands that mediate initial sperm–ZP binding. This novel model will be reviewed. A major challenge is to develop an alternate model for sperm–ZP binding that fits as much of the data as possible. Such a model is presented in this review. This paradigm could explain how the inability to cleave ZP2mut in ZP2mut mice could result in continued sperm binding to two-cell stage embryos without the formation of a supramolecular binding complex. These novel insights should guide future experiments that will eventually determine the molecular basis underlying gamete binding in the mouse and other eutherian mammals.

Insights into the binding specificity and catalytic mechanism ofN-acetylhexosamine 1-phosphate kinases through multiple reaction complexes

2014 ◽  
Vol 70 (5) ◽  
pp. 1401-1410 ◽  
Author(s):  
Kuei-Chen Wang ◽  
Syue-Yi Lyu ◽  
Yu-Chen Liu ◽  
Chin-Yuan Chang ◽  
Chang-Jer Wu ◽  
...  
Keyword(s):  
Molecular Basis ◽  
Catalytic Mechanism ◽  
Structural Information ◽  
Bifidobacterium Longum ◽  
Three Dimensional ◽  
Binding Specificity ◽  
Chemoenzymatic Synthesis ◽  
Leloir Pathway ◽  
The Given

Utilization ofN-acetylhexosamine in bifidobacteria requires the specific lacto-N-biose/galacto-N-biose pathway, a pathway differing from the Leloir pathway while establishing symbiosis between humans and bifidobacteria. The genelnpBin the pathway encodes a novel hexosamine kinase NahK, which catalyzes the formation ofN-acetylhexosamine 1-phosphate (GlcNAc-1P/GalNAc-1P). In this report, seven three-dimensional structures of NahK in complex with GlcNAc, GalNAc, GlcNAc-1P, GlcNAc/AMPPNP and GlcNAc-1P/ADP from bothBifidobacterium longum(JCM1217) andB. infantis(ATCC15697) were solved at resolutions of 1.5–2.2 Å. NahK is a monomer in solution, and its polypeptide folds in a crescent-like architecture subdivided into two domains by a deep cleft. The NahK structures presented here represent the first multiple reaction complexes of the enzyme. This structural information reveals the molecular basis for the recognition of the given substrates and products, GlcNAc/GalNAc, GlcNAc-1P/GalNAc-1P, ATP/ADP and Mg2+, and provides insights into the catalytic mechanism, enabling NahK and mutants thereof to form a choice of biocatalysts for enzymatic and chemoenzymatic synthesis of carbohydrates.

Three-Dimensional Structure of ras p21 Proteins

1989 ◽  
pp. 27-34 ◽  
Author(s):  
A. M. de Vos ◽  
L. Tong ◽  
M. V. Milburn ◽  
P. M. Matias ◽  
S.-H. Kim
Keyword(s):  
Three Dimensional ◽  
Dimensional Structure ◽  
Three Dimensional Structure ◽  
Ras P21 ◽  
P21 Proteins

scholarly journals Molecular basis of human 46X,Y sex reversal revealed from the three-dimensional solution structure of the human SRY-DNA complex

Cell ◽  
1995 ◽  
Vol 81 (5) ◽  
pp. 705-714 ◽  
Author(s):  
Milton H Werner ◽  
Jeffrey R Huth ◽  
Angela M Gronenborn ◽  
G Marius Clore
Keyword(s):  
Molecular Basis ◽  
Solution Structure ◽  
Three Dimensional ◽  
Sex Reversal ◽  
Dimensional Solution ◽  
Dna Complex

scholarly journals The Molecular Basis of Different Approaches for the Study of Cancer Stem Cells and the Advantages and Disadvantages of a Three-Dimensional Culture

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2615
Author(s):  
Danila Cianciosi ◽  
Johura Ansary ◽  
Tamara Y. Forbes-Hernandez ◽  
Lucia Regolo ◽  
Denise Quinzi ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cancer Stem Cells ◽  
Molecular Basis ◽  
Myeloid Leukemia ◽  
Three Dimensional ◽  
Specific Cell ◽  
Advantages And Disadvantages ◽  
Tumorigenic Potential ◽  
Three Dimensional Culture ◽  
Specific Cell Surface

Cancer stem cells (CSCs) are a rare tumor subpopulation with high differentiation, proliferative and tumorigenic potential compared to the remaining tumor population. CSCs were first discovered by Bonnet and Dick in 1997 in acute myeloid leukemia. The identification and isolation of these cells in this pioneering study were carried out through the flow cytometry, exploiting the presence of specific cell surface molecular markers (CD34+/CD38−). In the following years, different strategies and projects have been developed for the study of CSCs, which are basically divided into surface markers assays and functional assays; some of these techniques also allow working with a cellular model that better mimics the tumor architecture. The purpose of this mini review is to summarize and briefly describe all the current methods used for the identification, isolation and enrichment of CSCs, describing, where possible, the molecular basis, the advantages and disadvantages of each technique with a particular focus on those that offer a three-dimensional culture.

Structural Basis for Prereceptor Modulation of Plant Hormones by GH3 Proteins

Science ◽  
2012 ◽  
Vol 336 (6089) ◽  
pp. 1708-1711 ◽  
Author(s):  
Corey S. Westfall ◽  
Chloe Zubieta ◽  
Jonathan Herrmann ◽  
Ulrike Kapp ◽  
Max H. Nanao ◽  
...  
Keyword(s):  
Amino Acids ◽  
Conformational Changes ◽  
Molecular Basis ◽  
Biochemical Analysis ◽  
Plant Hormone ◽  
Three Dimensional ◽  
Structural Basis ◽  
Hormone Action ◽  
Plant Signaling ◽  
Carboxyl Terminal

Acyl acid amido synthetases of the GH3 family act as critical prereceptor modulators of plant hormone action; however, the molecular basis for their hormone selectivity is unclear. Here, we report the crystal structures of benzoate-specific Arabidopsis thaliana AtGH3.12/PBS3 and jasmonic acid–specific AtGH3.11/JAR1. These structures, combined with biochemical analysis, define features for the conjugation of amino acids to diverse acyl acid substrates and highlight the importance of conformational changes in the carboxyl-terminal domain for catalysis. We also identify residues forming the acyl acid binding site across the GH3 family and residues critical for amino acid recognition. Our results demonstrate how a highly adaptable three-dimensional scaffold is used for the evolution of promiscuous activity across an enzyme family for modulation of plant signaling molecules.

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