Formation of the spliceosome, a ribonucleoprotein apparatus that catalyzes nuclear mRNA splicing via transesterification reactions.

The process by which a cell irreversibly increases in size in one [spatial] dimension or along one axis.

The breakdown into simpler components of steroids, compounds with a 1,2,cyclopentanoperhydrophenanthrene nucleus.

The breakdown into simpler components of cholesterol, cholest-5-en-3 beta-ol, the principal sterol of vertebrates and the precursor of many steroids, including bile acids and steroid hormones.

Catalysis of the introduction of a C-5 double bond in the B ring of ergosterol.

Interacting selectively with a steroid, any of a large group of substances that have in common a ring system based on 1,2-cyclopentanoperhydrophenanthrene.

Interacting selectively with any androgen, male sex hormones.

Interacting selectively with vitamin D, a fat soluble vitamin that contributes to the maintenance of normal levels of calcium and phosphorus in the human bloodstream. Vitamin D is also known as calciferol and five different forms are known, including ergocalciferol and cholecalciferol.

Catalysis of the transfer of a hydroxyl group from 2-oxoglutarate to a prolyl residue in a protein.

Catalysis of the reaction: peptidyl-proline (omega=180) = peptidyl-proline (omega=0).

Catalysis of the reaction: peptidyl L-proline + 2-oxoglutarate + O2 = procollagen trans-4-hydroxy-L-proline + succinate + CO2.

Any of the spindle microtubules that radiate in all directions from the spindle poles and are thought to contribute to the forces that separate the poles and position them in relation to the rest of the cell.

Catalysis of the rearrangement of both intrachain and interchain disulfide bonds in proteins.

Interacting selectively with monomeric actin, also known as G-actin.

ATPase activity, coupled to transmembrane movement of ions, phosphorylative mechanism

Catalysis of the reaction: ATP + H2O = ADP + phosphate, to directly drive the transport of ions across a membrane. The reaction is characterized by the transient formation of a high-energy aspartyl-phosphoryl-enzyme intermediate.