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.
The inner membrane of the nucleus is the membrane which separates the nuclear matrix from the intermembrane space. In mammals, the inner nuclear membrane is associated with heterochromatin and the nuclear lamina.
The membrane surrounding the nucleus. This term is used when it is not known if the protein is found in or associated with the inner or outer nuclear membrane.
The outer membrane of the nucleus is the membrane facing the cytoplasm. In mammals, the outer nuclear membrane is continuous in many places with the rough endoplasmic reticulum and is dotted with ribosomes.
Functions in lipid transport from the endoplasmic reticulum and is involved in a wide array of cellular functions probably through regulation of the biogenesis of lipid microdomains at the plasma membrane (PubMed:12730355). Involved in the regulation of different receptors it plays a role in BDNF signaling and EGF signaling. Also regulates ion channels like the potassium channel and could modulate neurotransmitter release. Plays a role in calcium signaling through modulation together with ANK2 of the ITP3R-dependent calcium efflux at the endoplasmic reticulum. Plays a role in several other cell functions including proliferation, survival and death. Originally identified for its ability to bind various psychoactive drugs it is involved in learning processes, memory and mood alteration (PubMed:11149946, PubMed:14622179, PubMed:15571673, PubMed:15777781, PubMed:23332758, PubMed:9425306, PubMed:9603192). Necessary for proper mitochondrial axonal transport in motor neurons, in particular the retrograde movement of mitochondria (PubMed:25678561). Plays a role in protecting cells against oxidative stress-induced cell death via its interaction with RNF112 (PubMed:26792191). {Experimental EvidencePubMed:11149946, Experimental EvidencePubMed:12730355, Experimental EvidencePubMed:14622179, Experimental EvidencePubMed:15571673, Experimental EvidencePubMed:15777781, Experimental EvidencePubMed:23332758, Experimental EvidencePubMed:25678561, Experimental EvidencePubMed:26792191, Experimental EvidencePubMed:9425306, Experimental EvidencePubMed:9603192}.
Endoplasmic reticulum chaperone BiP (EC 3.6.4.10) (78 kDa glucose-regulated protein) (GRP-78) (Binding-immunoglobulin protein) (BiP) (Heat shock protein 70 family protein 5) (HSP70 family protein 5) (Heat shock protein family A member 5) (Immunoglobulin heavy chain-binding protein)
National and Kapodistrian University of Athens
Department of Biology
Biophysics & Bioinformatics Laboratory