A fluorimetric immunoassay has been used to assess reactivity of rheumatoid factor (RF) with both histone proteins and other basic polycations (poly-L-lysine, poly-L-ornithine, and protamine) bound to an immobilised tyrosine-glutamic acid polyanionic copolymer. Isolated RF preparations can bind to histone proteins in this assay, notably to H3 and H4 histones, and this activity was always masked...

x-linked agammaglobulinemia (xla) is an immunodeficiency caused by mutations in the bruton tyrosine kinase (btk) gene. in order to identify the mutations in btk gene in iranian patients with antibody deficiency, 13 male patients with an xla phenotype from 11 unrelated families were enrolled as the subjects of investigation for btk mutation analysis using pcr-sscp followed by sequencing. five di...

Tyrosine specific protein kinase activity was determined in 70 speci mens of the human mammary gland. These included 28 cancers of the breast, 21 benign breast diseases, and 21 normal breast tissues. We measured tyrosine kinase activity in the cytosol fraction and in the membrane fraction of the homogenates. In addition cytosolic aldolase activity was measured. Tyrosine kinase activity was dete...

Resilin is an elastic rubber-like protein found in the cuticles of insects. It incorporates outstanding properties high resilience and fatigue lifetime, where kinetic energy storage needed for biological functions such as flight jumps. Since resilin rich tyrosine groups, localized photopolymerization enabled due to ability introduce di-tyrosine bonds by a ruthenium-based photoinitiator. Using M...

Copolymer 1 [Cop 1, poly(Y,E,A,K)] is a random synthetic amino acid copolymer of L-tyrosine, L-glutamic acid, L-alanine and L-lysine, effective both in suppression of experimental allergic encephalomyelitis and in the treatment of relapsing forms of multiple sclerosis. Cop 1 binds promiscuously and very efficiently to purified human HLA-DR molecules within the peptide-binding groove. In the pre...

The activity of calmodulin (CaM) is modulated not only by oscillations in the cytosolic concentration of free Ca(2+), but also by its phosphorylation status. In the present study, the role of tyrosine-phosphorylated CaM [P-(Tyr)-CaM] on the regulation of the epidermal growth factor receptor (EGFR) has been examined using in vitro assay systems. We show that phosphorylation of CaM by rat liver s...

The present work deals with the synthesis and characterization of a novel nucleoamino acid derivative based on a l-tyrosine moiety to which a thymine nucleobase was anchored by means of an amide bond to the N-alpha group. This derivative, denominated by us TyrT, belongs to the family of the nucleobase-amino acid conjugates that show a wide range of biological activities, frequently associated w...