[Alteration in the expression of platelet microRNAs in diseases with abnormal platelet activation].

MicroRNAs (miRNA) are short, non-coding RNAs consisting of 18-25 nucleotides that regulate posttranscriptionally the gene expression involved in the regulation of physiological processes of the cells. Their key role is to modulate the translation of target mRNAs via binding to complementary sequences within the 3' UTRs of mRNAs resulting in altered protein synthesis or even the degradation of mRNAs. miRNAs are carried not only by cells with nucleus, but also in platelets, red blood cells, and they are present in the circulation, in urine and in other body fluids as well.