Numerous key biological processes rely on the concept of multivalency, where ligands achieve stable binding only upon engaging multiple receptors. These processes, like viral entry or immune synapse formation, occur diffusive cellular membrane. One crucial, yet underexplored aspect multivalent is mobility coupled Here, we discuss consequences in from four perspectives: (I) The facilitation rece...

The insulin-like growth factor I (IGF I) receptor is a tyrosine kinase-containing transmembrane protein that plays an important role in cell growth control. We have isolated and characterized human genomic DNA clones containing the entire coding sequence of the IGF I receptor. Results of restriction analysis and sequencing of multiple overlapping clones were consistent with the existence of a s...

introduction  insulin-like growth factor i (igf-i) which is produced in abundance in the normal adult liver, is deeply involved in hepatocyte survival, growth, and differentiation during liver development. igf-i plays the roles via the receptor (igf-ir) signaling pathway. igf-ir unlike igf-i is expressed strongly in the developing liver, but much more weakly in adults. objective:  we hypothesiz...

Blocking alphaVbeta3 integrin occupancy results in attenuation of the cellular migration response to insulin-like growth factor I (IGF-I). To determine whether integrin antagonists alter other IGF-I-stimulated biologic actions, quiescent smooth muscle cells (SMCs) were exposed to echistatin and their ability to respond to IGF-I was determined. Echistatin (10(-7) M) inhibited IGF-I-stimulated DN...

The effects of intraperitoneal injection of N6-cyclohexyladenosine (CHA, a selective adenosine A1 receptor agonist) and 8-cyclopenthyle-I-3-dimethylexanthine (CPT, a selective adenosine A1 receptor antagonist) on entorhinal cortex-kindled seizures were investigated. Fully entorhinal cortex-kindled rats received normal saline (control), CHA (0.06, 0.12 and 0.25 mg/kg) or CPT (0.06 and 0.12 mg/kg...

interferons (ifns) are a family of small regulatory glycoproteins that play a central role in the defense against viral infections. although ifns have been initially discovered as antiviral factors, today they are known as an integral part of the cytokine network that affect a wide range of biological processes. ifns exert their pleiotropic effects through their multisubunit cell surface recept...

Transforming growth factor beta (TGF-beta), a multifunctional cytokine that regulates a variety of biological functions, signals through a heteromeric receptor complex of the type I and type II TGF-beta receptors. The type II receptor, a transmembrane serine-threonine kinase, was cloned based on its ability to directly bind TGF-beta. Recently, a number of candidate type I TGF-beta receptors hav...

We have previously shown that circulating progenitor cells in patients with polycythemia vera (PV) are hypersensitive to insulin-like growth factor I (IGF-I) with respect to erythroid burst formation in serum-free medium, and that this effect occurs through the IGF-I receptor. To investigate the molecular basis of this IGF-I hypersensitivity phenomenon, we examined tyrosine phosphorylation of t...

There are two types of insulin-like growth factor (IGF) receptors. The type I receptor generally binds IGF-I more tightly than IGF-II and also interacts weakly with insulin. The type II receptor prefers IGF-II over IGF-I and does not recognize insulin. The type I receptor is made up of an alpha binding subunit (Mr 130000) and a beta subunit (Mr 95 000) probably organized as a heterotetramer (Oi...

Background: TGF-β isoforms play crucial roles in diverse cellular processes. Therefore, targeting and inhibiting TGF-β signaling pathway provides a potential therapeutic opportunity. TGF-β isoforms bind and bring the receptors (TβRII and TβRI) together to form a signaling complex in an ordered manner. Objectives: Herein, an antagonistic variant of TGF-β (AnTβ)...