The modification of proteins with ubiquitin is an important cellular mechanism for targeting abnormal or short-lived proteins for degradation. Ubiquitination involves at least three classes of enzymes: ubiquitin-activating enzymes, or E1s, ubiquitin-conjugating enzymes, or E2s, and ubiquitin-protein ligases, or E3s. This gene encodes a member of the E2 ubiquitin-conjugating enzyme family. Four alternatively spliced transcript variants encoding the same protein have been found for this gene. [p

Lamins are nuclear membrane proteins that serve to maintain specific cellular functions, such as DNA replication and chromatin organization. Lamin B receptor (LBR) is an integral protein of the nuclear envelope inner membrane. It is phosphorylated by CDC2 protein kinase in mitosis when the inner nuclear membrane breaks down into vesicles that dissociate from the lamina and the chromatin. It is phosphorylated by different protein kinases in interphase when the membrane is associated with these

Early endosomes are cytoplasmic compartments that function in receiving and sorting endocytosed proteins for vesicular transport. EEA1 (early endosome antigen 1) is a peripheral membrane protein that co-localizes with the transferrin receptor and Rab5 on early endosomes. EEA1 contains a calmodulin-binding IQ motif and cysteine rich finger motif necessary for its specific localization to the early endosomes. EEA1 has sequence homology to several yeast proteins that have been implicated in mem

Midkine exhibits neurite outgrowth-promoting activity and may play a role in nervous system development and/or maintenance. Its expression is predominant only for a short period from approximately one-half to two-thirds of the way through gestation; before and after that, it is barely detectable. Midkine was first found in differentiating mouse teratocarcinoma cells. It has neurotrophic activities and is mitogenic to certain, but not to all, fibroblast cell lines.

Glutamate receptors constitute the principal excitatory neurotransmitter receptors in brain. Two classes of glutamate receptors exist: Ionotropic receptors, and metabotropic receptors (mGluRs). Metabotropic Glutamate Receptor 5b (GRM5) activity is mediated by a G-protein that activates a phosphatidylinositol-calcium second messenger system and generates a calcium-activated chloride current. The metabotropic glutamate receptor type 5 (mGlu5) is expressed in two splice variants, mGlu5a and mGl