 Perichromatin fibrils are visible only under electron microscope . They are located next to the transcriptionally active chromatin and are hypothesized to be the sites of active pre @-@ mRNA processing . 
 Perichromatin fibrils <a href='drop_aux' title='1'><mark>are</mark></a>visible only under electron microscope . They are located next to the transcriptionally active chromatin and are hypothesized to be the sites of active pre @-@ mRNA processing . 
Perichromatin fibrils visible only under electron microscope . They r located next to da transcriptionally active chromatin and are hypothesized to b the sites of active pre @-@ mRNA processing .