A small, dense body one or more of which are present in the nucleus of eukaryotic cells. It is rich in RNA and protein, is not bounded by a limiting membrane, and is not seen during mitosis. Its prime function is the transcription of the nucleolar DNA into 45S ribosomal-precursor RNA, the processing of this RNA into 5.8S, 18S, and 28S components of ribosomal RNA, and the association of these components with 5S RNA and proteins synthesized outside the nucleolus. This association results in the formation of ribonucleoprotein precursors; these pass into the cytoplasm and mature into the 40S and 60S subunits of the ribosome.

The formation of mature insulin by proteolysis of the precursor preproinsulin. The signal sequence is first cleaved from preproinsulin to form proinsulin; proinsulin is then cleaved to release the C peptide, leaving the A and B chains of mature insulin linked by disulfide bridges.

The formation from simpler components of any amino sugar, sugars containing an amino group in place of a hydroxyl group.

regulation of mitotic metaphase/anaphase transition

Any process that modulates the frequency, rate or extent of the onset of anaphase (chromosome movement) in the mitotic cell cycle.

A complex composed of RNA of the small nucleolar RNA (snoRNA) and protein, found in the nucleolus of a eukaryotic cell. Most are involved in a step of processing of rRNA: cleavage, 2'-O-methylation, or pseudouridylation. The majority, though not all, fall into one of two classes, box C/D type or box H/ACA type.

The regulated release of a peptide hormone from secretory granules.

The regulated release of proinsulin from secretory granules (B granules) in the B cells of the pancreas; accompanied by cleavage of proinsulin to form mature insulin.

RNA polymerase I, one of three eukaryotic nuclear RNA polymerases, is a multisubunit complex; it produces rRNAs. Two large subunits comprise the most conserved portion including the catalytic site and share similarity with other eukaryotic and bacterial multisubunit RNA polymerases. The remainder of the complex is composed of smaller subunits (generally ten or more), some of which are also found in RNA polymerase III and others which are found in all three nuclear RNA polymerases. Although the core is competent to mediate ribonucleic acid synthesis, it requires additional factors to select the appropriate template.