BDNF is the neurotrophin mediating pro-neuronal survival and plasticity. Cortisol (COR), in turn, is engaged in the coordination of several processes in the brain homeostasis. Stress-responsive, both factors show an integrative role through their receptor's dynamics in neurophysiology. Furthermore, the Val66Met BDNF polymorphism may play a role in this mechanism. to investigate BDNF-COR interaction in the human neurophysiology context. We collected all papers containing BDNF and COR parameters or showing COR analyses in genotyped individuals in a PubMed search - full description available on PROSPERO - CRD42016050206. BDNF and COR perform distinct roles in the physiology of the brain whose systems are integrated by glucocorticoid receptors dynamics. The BDNF polymorphism appears to have an influence on individual COR responsivity to stress. BDNF and COR play complementary roles in the nervous system where COR is a regulator of positive/negative effects. Exercise positively regulates both factors, regardless of BDNF polymorphism.
Most proteases are synthesized in the cell as precursor-containing propeptides. These structural elements can determine the folding of the cognate protein, function as an inhibitor/activator peptide, mediate enzyme sorting, and mediate the protease interaction with other molecules and supramolecular structures. The data presented in this review demonstrate modulatory activity of propeptides irrespective of the specific mechanism of action. Changes in propeptide structure, sometimes minor, can crucially alter protein function in the living organism. Modulatory activity coupled with high variation allows us to consider propeptides as specific evolutionary modules that can transform biological properties of proteases without significant changes in the highly conserved catalytic domains. As the considered properties of propeptides are not unique to proteases, propeptide-mediated evolution seems to be a universal biological mechanism.
Proprotein convertases (PCs) is a protein family which includes nine highly specific subtilisin-like serine endopeptidases in mammals. The system of PCs is involved in carcinogenesis and levels of PC mRNAs alter in cancer, which suggests expression status of PCs as a possible marker for cancer typing and prognosis. The goal of this work was to assess the information value of expression profiling of PC genes. Quantitative polymerase chain reaction was used for the first time to analyze mRNA levels of all PC genes as well as matrix metalloproteinase genes MMP2 and MMP14, which are substrates of PCs, in 30 matched pairs of samples of human lung cancer tumor and adjacent tissues without pathology. Significant changes in the expression of PCs have been revealed in tumor tissues: increased FURIN mRNA level (p<0.00005) and decreased mRNA levels of PCSK2 (p<0.007), PCSK5 (p<0.0002), PCSK7 (p<0.002), PCSK9 (p<0.00008), and MBTPS1 (p<0.00004) as well as a tendency to increase in the level of PCSK1 mRNA. Four distinct groups of samples have been identified by cluster analysis of the expression patterns of PC genes in tumor vs. normal tissue. Three of these groups covering 80% of samples feature a strong elevation in the expression of a single gene in cancer: FURIN, PCSK1, or PCSK6. Thus, the changes in the expression of PC genes have a limited number of scenarios, which may reflect different pathways of tumor development and cryptic features of tumors. This finding allows to consider the mRNAs of PC genes as potentially important tumor markers.
BDNF and its specialized receptor TrkB are expressed in the developing lateral line system of zebrafish, but their role in this organ is unknown. To tackle this problem in vivo, we used transgenic animals expressing fluorescent markers in different cell types of the lateral line and combined a BDNF gain-of-function approach by BDNF mRNA overexpression and by soaking embryos in a solution of BDNF, with a loss-of-function approach by injecting the antisence ntrk2b-morpholino and treating embryos with the specific Trk inhibitor K252a. Subsequent analysis demonstrated that the BDNF-TrkB axis regulates migration of the lateral line primordium. In particular, BDNF-TrkB influences the expression level of components of chemokine signaling including Cxcr4b, and the generation of progenitors of mechanoreceptors, at the level of expression of Atoh1a-Atp2b1a.