Towards universal approach for bacterial production of three-finger Ly6/uPAR proteins: Case study of cytotoxin I from cobra N. oxiana.

Cytotoxins or cardiotoxins is a group of polycationic toxins from cobra venom belonging to the 'three-finger' protein superfamily (Ly6/uPAR family) which includes small β-structural proteins (60-90 residues) with high disulfide bond content (4-5 disulfides). Due to a high cytotoxic activity for cancer cells, cytotoxins are considered as potential anticancer agents. Development of the high-throughput production methods is required for the prospective applications of cytotoxins.

[INVOLVEMENT OF 5-HT1A RECEPTORS IN LONG-TERM INFLUENCE OF INFLAMMATORY PAIN AND STRESS IN EARLY AGE ON REACTIVITY OF NOCICEPTIVE SYSTEM].

Effects of inflammatory pain, short stress of maternal isolation and combination of these impacts in 1-day-old and repeatedly 2-day-old rat pups (neonatal period of development) on the indices of generalized pain and the inflammatory pain response were studied on the rats during the adulthood. To study the involvement of 5-HT1A receptors in the long-term impact of neonatal effects on pain sensitivity we used a chronic injection of 5-HT1A receptor agonist buspirone during the prepuberal period of rats which as newborn experienced similar impacts (control, injection of saline). It was found that in adult rats in which inflammatory pain and stress of maternal isolation during the first two days of life caused changes in pain sensitivity, buspirone normalized the indices of basic pain in the hot plate test and the pain response in the formalin test; the combination of these impacts did not cause any changes in the pain sensitivity, and the effect of buspirone did not appear.

[LONG-TERM EFFECTS OF STRESSFUL IMPACTS DURING NEONATAL PERIOD OF DEVELOPMENT ON NOCICEPTIVE SYSTEM AND PSYCHOEMOTIONAL BEHAVIOR].

Long-term effects of peripheral pain, brief stress of maternal isolation and their combination in one-day- and repeatedly two-day-old rat pups or seven-day- and repeatedly eight-day-old pups were investigated on indices of basal pain (in the absence of inflammation), a prolonged response to again evoked inflammation in the formalin test, the level of anxiety and depression and of spatial learning ability in the animals as adults (90-day-olds). Changes in the indices under investigation were revealed in adult rats depending on the type of early life impact and age during which it occurred: inflammatory pain induced hypoalgesia in the test of hot plate and deterioration in spatial learning ability in the Morris test; the stress of maternal isolation on the first and second days, but not seventh and eighth days of life caused a strengthening of formalin-induced pain response. Regardless of the age when rat pups were exposed to impact, again induced inflammation evoked strengthening of pain response when the animals reached adulthood.

Human Secreted Ly-6/uPAR Related Protein-1 (SLURP-1) Is a Selective Allosteric Antagonist of α7 Nicotinic Acetylcholine Receptor.

SLURP-1 is a secreted toxin-like Ly-6/uPAR protein found in epithelium, sensory neurons and immune cells. Point mutations in the slurp-1 gene cause the autosomal inflammation skin disease Mal de Meleda. SLURP-1 is considered an autocrine/paracrine hormone that regulates growth and differentiation of keratinocytes and controls inflammation and malignant cell transformation.

Point mutations in dimerization motifs of the transmembrane domain stabilize active or inactive state of the EphA2 receptor tyrosine kinase.

The EphA2 receptor tyrosine kinase plays a central role in the regulation of cell adhesion and guidance in many human tissues. The activation of EphA2 occurs after proper dimerization/oligomerization in the plasma membrane, which occurs with the participation of extracellular and cytoplasmic domains. Our study revealed that the isolated transmembrane domain (TMD) of EphA2 embedded into the lipid bicelle dimerized via the heptad repeat motif L(535)X3G(539)X2A(542)X3V(546)X2L(549) rather than through the alternative glycine zipper motif A(536)X3G(540)X3G(544) (typical for TMD dimerization in many proteins).