In this review we discuss the structural elements of CD44 that have been shown to be involved in specific functions. To this end, we focus primarily on experiments in which CD44 constructs are transfected into cells whose function is then assayed. The hyaluronan binding function of CD44 has been assayed in cell lines and in fusion proteins, termed CD44-Igs, consisting of the external domain of CD44 coupled to the hinge, CH2 and CH3 regions of human IgG1. These studies have shown that hyaluronan binding by CD44 is regulated by the cells in which it is expressed, and that at least part of this regulation is determined by cell specific posttranslational modifications, especially N-glycosylation, of CD44 itself. Variant isoforms of CD44 determined by alternative splicing of 11 optional exons in the middle of the gene determine additional functions of CD44, as well as contributing to the regulation of hyaluronan binding. Soluble CD44 may modulate the function of cell surface CD44. The cytoplasmic domain of CD44 contributes to ligand binding in a way that remains obscure. It also determines membrane localization in polarized epithelial cells, and is probably involved in CD44 interactions with the cytoskeleton and in mediating post-ligand binding events.

Cited by 174Open access

Superantigens: Structure-function relationships

Matthew Baker, K. Ravi Acharya · International Journal of Medical Microbiology · 2004

Cited by 103

From structure to function

Armin Durmisevic · Open MIND · 2025

DNA G-quadruplexes are four-stranded secondary DNA structures formed through Hoogsten hydrogen bonds of four individual guanines, creating a G-tetrad whereby several of such tetrads can stack on top of each other to create the final construct. They are closely involved in the regulation of several biological processes such as transcription and translation, core mechanisms of life on earth. This makes them prime targets for several therapeutic approaches. Amongst them is the development of small molecule ligands capable of targeting and stabilising or destabilising G-quadruplex structures. Yet their polymorphic character and their complex interaction with other biomolecules, primarily proteins, remains a challenging aspect of understanding G-quadruplex chemical and biological features. Concomitantly this renders them an interesting playground to introduce modifications into these systems that potentially offer a novel understanding of their characteristics. In this thesis, a novel artificial bipyridine ligandoside was incorporated covalently into short DNA oligonucleotides capable of forming G-quadruplex structures. It was shown that these modifications had little to no impact on the parental structure, retaining the original topology and thermal stability. Although almost all sequences showed thermal stabilisation to some degree through complex formation of the bipyridine moieties and divalent metal cations such as Cu2+, Ni2+, Zn2+, Co2+, Cd2+ and Fe2+, only few G-quadruplexes experienced a structural reorganisation resulting in a novel distinct topology. Of these particular examples, kinetic experiments revealed how the refolding was mostly driven by hydrogen bond and π-stacking interactions of the DNA structure and merely kinetically enables through the initial fast formation of the metal complex. Furthermore, it was showcased that these artificial G-quadruplexes retained interaction capabilities with proteins and in particular helicases Pif1 and DHX36. As the topology of some modified G-quadruplexes was metal dependent, the resulting binding constants (Kd) where impacted as preferential interaction with either hybrid, antiparallel or parallel topologies was observed. For the best systems low nM Kd values could be obtained while taking advantage of the thermal stabilisation by the metal complex and thus greatly impeding the unwinding the G-quadruplex structure proven by luciferase assays. Lastly, these modified systems were transfected into human cancer cell lines HeLa and U2OS where their spontaneous localisation into the cell nucleus as well as the retention of their structure stabilised ideally by Ni2+ cations be proven by fluorescence based microscopy. Overall, these novel modified G-quadruplex systems bearing bipyridine modifications granted a more detailed insight into structural properties of these DNA secondary structures and also made for promising novel therapeutic approaches and an application as potential molecular decoy.

Cited by 0

Photon Structure Function Revisited

Christoph Berger · Journal of Modern Physics · 2015

The flux of papers from electron positron colliders containing data on the photon structure function ended naturally around 2005. It is thus timely to review the theoretical basis and confront the predictions with a summary of the experimental results. The discussion will focus on the increase of the structure function with x (for x away from the boundaries) and its rise with , both characteristics being dramatically different from hadronic structure functions. The agreement of the experimental observations with the theoretical calculations is a striking success of QCD. It also allows a new determination of the QCD coupling constant which very well corresponds to the values quoted in the literature.

Cited by 9Open access

MTHFD structure and function.

Fernando Maiello (8837069), Gloria Gallo (8837072), Camila Coelho (8837075) et al. · Figshare · 2020

(A) MTHFD catalyzes the conversion of 5,10‐methylenetetrahydrofolate via 5,10-methenyltetrahydrofolate to 10-formyltetrahydrofolate in a NADP+ dependent manner. (B) Secondary structural elements of the T. thermophilus MTHFD dimer. Important structural elements are indicated. LL: lid loop, NTH: N-terminal helix, SBD: substrate binding domain, CH: connector helix, NBD: nucleotide binding domain, CTH: C-terminal helix. (C) 2Fo-Fc electron density map at the 1.0 σ level of the active site of T. thermophilus MTHFD showing the NADP+ nucleotide. (D) Alignment of Thermus thermophilus (red) Thermoplasma acidophilum (yellow) Acinetobacter baumannii (blue) crystal structures. (E) Amino acid sequence alignment of MTHFD from T. thermophilus, T. acidophilum and A. baumannii with secondary structure elements (α-helices, β-strands as arrows) of T. thermophilus indicated above sequences. Numbering (indicated by dots) refers to the T. thermophilus sequence.

Cited by 0Open access

Lipotubuloids - Structure and Function

Maria Kwiatkowska, Katarzyna Poposka, Dariusz Stpiski et al. · InTech eBooks · 2012

Rozdział 17 książki: Advances in Selected Plant Physiology Aspects\nEdited by Dr. Giuseppe Montanaro

Cited by 3Open access

Plant Structure and Function

Cecie Starr, Ralph E. Taggart · Medical Entomology and Zoology · 1995

V: PLANT STRUCTURE AND FUNCTION. 29. Plant Tissues. 30. Plant Nutrition and Transport. 31. Plant Reproduction. 32. Plant Growth and Development.

Cited by 30

Plant Function and Structure

Gregory N. Brown · Forest Science · 1974

Cited by 0

antibodies structure and function

Shane Burke · Zenodo (CERN European Organization for Nuclear Research) · 2024

Cited by 0Open access

Structure-function in smokers

Sylvia Verbanck · VUBIR (Vrije Universiteit Brussel) · 2024

Cited by 0Open access

Antibody structure and function

Marks, C · OpenGrey (Institut de l'Information Scientifique et Technique) · 1992

Available from British Library Document Supply Centre- DSC:D062802 / BLDSC - British Library Document Supply Centre

Cited by 1

Pectin Structure-Function Relationship

Naschla Gasaly Retamal · 2025

Our gut is home to trillions of microbes and lined with a protective barrier that keeps us healthy. When this barrier is weakened, as in conditions like inflammatory bowel disease (IBD), chronic inflammation can occur. The food that we eat, plays a key role in maintaining gut health, and one important ingredient that contributes to gut health are pectins, a type of fiber naturally found in fruits like apples and lemons. In this thesis, we studied how different types of pectin, specifically low and high methyl-esterified pectins, affect gut health. Using advanced in vitro models, including human intestinal cell lines and organoids (mini-gut structures grown in the lab), we found that low-methyl pectin could reduce inflammation, protect gut barrier function, and support mucus production. These effects occurred both through interactions with immune receptors on the cells and by mimicking the action of microbial metabolites such as butyrate. While these results are promising, it is important to note that they were obtained in controlled laboratory conditions and not in patients. Pectins are not a cure for IBD, although our findings suggest that specific types of dietary fiber may have potential as part of a supportive treatment for gut health. Although we gained supportive results for a role for pectins in gut health and prevention of IBD, more research, especially in humans, is needed to confirm these effects and to explore how personalized nutrition might help manage chronic gut inflammation in the future.

Cited by 0Open access

Plasmodesmata: Structure and Function

Thomas David Geydan, Luz Marina Melgarejo, Luz Marina Melgarejo · SHILAP Revista de lepidopterología · 2006

Plasmodesmata are channels that transverse the cell wall and membrane. These specialized and non passive channels act like gates that facilitate and regulate both communication and transportation of molecules such as water, nutrients, metabolites and macromolecules between plant cells. In the last decade a new point of view of plasmodesmata has emerged, and studies have demonstrated that these channels are more complex. In this brief note, we pretend to expose the actual knowledge of plasmodesmata, focusing on their structure and function.

Cited by 1Open access

mRNA Structure and Function

James Darnell · Progress in nucleic acid research and molecular biology · 1977

Cited by 39