The nuclear envelope is a membrane system which surrounds the nucleoplasm of eukaryotic cells. It is composed of the nuclear lamina, nuclear pore complexes and two nuclear membranes. The space between the two membranes is called the nuclear intermembrane space.
Part of the first module of ergosterol biosynthesis pathway that includes the early steps of the pathway, conserved across all eukaryotes, and which results in the formation of mevalonate from acetyl-coenzyme A (acetyl-CoA) (PubMed:8896278, PubMed:19486165). Hmg1 catalyzes the reduction of hydroxymethylglutaryl-CoA (HMG-CoA) to mevalonate (PubMed:8896278, PubMed:19486165). The first module starts with the action of the cytosolic acetyl-CoA acetyltransferase eg10 that catalyzes the formation of acetoacetyl-CoA. The hydroxymethylglutaryl- CoA synthases erg13 then condenses acetyl-CoA with acetoacetyl-CoA to form HMG-CoA. The rate-limiting step of the early module is the reduction to mevalonate by the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductases hcs1 (Probable). {Experimental EvidencePubMed:19486165, Experimental EvidencePubMed:8896278, Curator Inference}.
National and Kapodistrian University of Athens
Department of Biology
Biophysics & Bioinformatics Laboratory