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| | Nuclear and cytoplasmic expression of NRP/B/ENC1 were demonstrated by immunostaining with specific anti-NRP/B/ENC1 antibody. Nuclear NRP/B/ENC1: (A) Human normal adult brain (frontal cortex), (B) U87-MG human glioblastoma cells. (C) Cytoplasmic NRP/B/ENC1: primary GBM cells. |
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| Description | 589AA and 66130 Da. NRP/B/ENC1 is a member of a growing family of proteins that contains two major structural elements: A BTB/POZ domain in the N-terminus and kelch motif in the C-terminus [See above]. The BTB/POZ domain, consisting of approximately 115 amino acids is found in several members of the kelch family. It is involved in protein-protein interactions and mediates both dimer and heterodimer formation. The kelch domain includes six repeats (each containing about 50 amino acids), which are implicated in actin binding, protein folding and/or protein-protein interactions. NRP/B/ENC1 encodes an unusually evolutionarily conserved protein between mouse and human. |
| Expression | NRP/B/ENC1 is expressed in the nervous system. NRP/B/ENC1 is expressed mostly in primary neurons, but not in primary astrocytes. NRP/B/ENC1 mRNA and protein expression were detected abundantly and observed in human primary brain tumors, including glioblastoma multiformae and astrocytoma, and in human neuroblastoma cell lines (IMR32, SK-N-MC, SK-N-SH), in glioblastoma cell lines (A172, T98G, U87-MG, U118-MG, U138-MG and U373-MG), and in neuroglioma (H4) and astrocytoma cell lines (CCF-STTG1 and SW1088). |
| Localisation | Nuclear (Glioblastoma, U87-MG) and Cytosolic (Glioblastoma, GBM). |
| Function | Evidence suggests that NRP/B/ENC1 is involved in multiple cell processes, including nervous system development, neuronal and adipocyte differentiation and brain tumorigenesis. NRP/B/ENC1 functions as an actin-binding protein that may be important in the organization of the actin cytoskeleton during neural fate specification and nervous system development, and plays a crucial role in the regulation of neuronal process formation via association with the hypophosphorylated form of retinoblastoma protein (p110RB). |
| Homology | NRP/B/ENC1 shares significant homology with the "kelch" repeats found in several kelch-related genes, including the Drosophila gene which is essential for oogenesis. |
| kelch encodes a component of intercellular bridges in Drosophila egg chambers. |
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