BI236 Lecture 15: BI236 – Gene Expression 5
Document Summary
If pairing is a perfect match mrna degradation is initiated by slicer (a ribonuclease component of sirisc) degraded complementary nuclear dna sequences and sirna silences the gene expression. If the match is imperfect translation of the mrna is inhibited without mrna being. In some cases, sirisc may enter the nucleus and be guided by its sirna to: micrornas (mirnas) A class of single-stranded rnas about 21-22 nt eukaryotic cells. Posttranslational modifications of protein structure, function: once polypeptide chain is formed - still many ways of regulating the activity of polypeptide chain, these are posttranslational control mechanisms that are available for modifying protein structure and function. Reversible structural alterations that influence protein function (protein phosphorylation and dephosphorylation) Permanent alterations such as proteolytic cleavage: mechanisms that control the amount of any given protein present in a cell is influenced by its - rate of degradation and.
