Introduction

• CNPase (2',3'-cyclic nucleotide 3'-phosphodiesterase)

• CNPase is an oligodendrocyte-related gene. PMID: 18289148

• CNPase is a known non-compact myelin protein (Watanabe, M., Sakurai, Y., Ichinose, T., Aikawa, Y., Kotani, M., Itoh, K., 2006. J. Neurosci. Res. 84, 525-533)

• CNPase is a myelin-specific enzyme and third most abundant myelin protein in the central nervous system (CNS). PMID: 15535987, PMID: 12225906, PMID: 9143234, PMID: 6280086

• CNPase is a protein related to axonal ensheathment by myelinating cells. PMID: 12898532

• CNPase is used as a myelin marker. PMID: 17306456

• The antigen labeled with mAb-Rip is CNP in the oligodendrocytes. PMID: 16786579

• CNPase, a member of the 2H phosphoesterase superfamily, is firmly bound to brain white matter and found mainly in the central nervous system of vertebrates. PMID: 15713463

• CNP, a protein of unknown function in vivo, is abundantly expressed in myelinating glia in two isoforms, CNP1 and CNP2. PMID: 14749525

• CNP is a membrane-bound microtubule-associated protein that can link tubulin to membranes and may regulate cytoplasmic microtubule distribution. PMID: 11842207

• CNPases are well-established markers of mammalian myelin. PMID: 10098837

• CNPase is a 48-kDa prenylated protein that associates with microtubules. PMID: 9280293

• CNPase is the earliest myelination specific polypeptide to be synthesized by oligodendrocytes (OLs). PMID: 7884818

Expression

• CNPase) is a myelin-associated enzyme. In central and peripheral nervous system tissues, the enzyme is localized almost exclusively in the two cell types that elaborate myelin, the oligodendrocyte and the Schwann cell, respectively. PMID: 2537684

• CNPase is a protein associated with oligodendrocyte/myelin membranes, also present in lymphocytes and retina. PMID: 9576757

• CNPase is a protein found abundantly in the cytoplasmic compartments of CNS myelin. Two isoforms of this protein, CNP1 and CNP2, are detectable. PMID: 10646504

• CNPase is an isoprenylated protein enriched in myelin and oligodendrocytes but also present in several other tissues at low levels. CNP binds avidly to membranes and in addition possesses several characteristics of cytoskeletal proteins. PMID: 8752099

• In tissue sections from paraformaldehyde-fixed rat brain the antigen was localized in oligodendrocytes. In cultured glial cells from newborn mice the antibody stained cells which were identified as oligodendrocytes by co-localization of myelin basic protein. PMID: 7877717

• CNP gene products were expressed exclusively by oligodendrocytes in the CNS. CNP mRNA was concentrated around oligodendrocyte perinuclear regions during all stages of myelination. PMID: 2842456

• Robust RIP immunoreactivity was present in Remak bundles in mixed nerves and in sympathetic ganglia and grey rami. Following peripheral nerve injury, RIP immunoreactivity was redistributed diffusely throughout de-differentiating Schwann cell cytoplasm. In uninjured rats, low levels of RIP immunoreactivity were detectable in satellite cells surrounding dorsal root ganglion (DRG) neurons and in terminal Schwann cells at neuromuscular junctions. PMID: 17229407

• Marrow stromal cells exhibited 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) at the plasma membrane and this has allowed their identification after transplantation by immunoelectron microscopy. In the control rats, the lesion site showed activated microglia/neural macrophages and some elongated cells, whose cytoplasm was immunoreactive for CNP. PMID: 17061258

• CNP is a widely expressed protein that is associated with mitochondria and provides new clues as to its cellular function outside of myelin structures. PMID: 9359886

• CNP was expressed in cytoplasm and plasma membrane of HeLa cells by transfection of its cDNA clone. PMID: 2161933

• The highest specific activities of CNPase were associated with the cells that elaborate myelin membrane in the central and peripheral nervous system, oligodendrocytes and Schwann cells, respectively. PMID: 2995854

• CNPase is localized on the plasma membranes of Schwann cells and is expressed by the cells in the absence of an axonal stimulus. PMID: 2983827

• CNP was localized to oligodendrocytes in the corpus callosum and subcortical white matter and gray matter. Also, nerve fibers appeared to be stained. PMID: 2580990

• CNPase is localized in the optic nerve fiber and photoreceptor layers of the chick retina. PMID: 6192212

• CNPase occurs not only in myelin fractions and glial cells, but can also be shown to be present in a CNS cell line of neuronal origin (B104). PMID: 6275035

• CNP is present in PNS myelin and preferentially localized in Schwann cell plasma membranes. PMID: 6255099

Function

• CNPase is an early expressed regulator of cellular events that culminate in CNS myelination. PMID: 8875429

• CNPaseII is important in myelinogenesis and possibly neuronal growth and repair. PMID: 8647287

• Reduced CNP expression in the schizophrenic brain is relevant to disease etiology and therefore provide support for the general hypothesis that altered oligodendrocyte function is an etiological factor in schizophrenia.

Applications

Immunoblot (IB)

• Immunoblot analysis indicated that both CNP1 and CNP2 isoforms are present in the CBL-PSD fraction, whereas there is little CNP2 in the forebrain (FB)-PSD fraction. Immunocytochemistry of dissociated cerebellar cultures revealed patchy CNP staining in oligodendrocytes (OLs), Purkinje cells (PCs), and unidentified PSD95-positive cells, but no staining in granule cells (GCs). PMID: 14503857

• By immunoblotting, using two distinct anti-CNP monoclonal antibodies, CNP was detected in medullary cell cultures and expression of CNP was confirmed by reverse transcription and PCR amplification. PMID: 9359886

• A method is presented for the separation and detection of the myelin marker enzyme 2',3'-cyclic nucleotide 3'-phosphodiesterase on isoelectric focusing gels and by immunoblotting. PMID: 2162637

Immuno-Electron Microscopy (IEM)

• In a light and electron microscopic immunocytochemical study we have examined the distribution of myelin basic protein (MBP), 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP), and myelin/oligodendroglial glycoprotein (MOG) within CNS myelin sheaths and oligodendrocytes of adult Sprague-Dawley rats. PMID: 2462020

• Oligodendrocytes or their putative progenitors were the only cells found to be immunoreactive to polyclonal antisera against the enzyme 2'3'-cyclic nucleotide 3'-phosphodiesterase (CNP) in developing and mature brains of rats and mice, as visualized by light and electron microscopy. PMID: 2842470

Immunofluorescence (IF)

• Primary cultures of Schwann cells were labeled by indirect immunofluorescence using an antibody directed against 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase). PMID: 2983827

• Immunofluorescence demonstration of 2':3'-cyclic-nucleotide 3'-phosphodiesterase in cultured oligodendrocytes of mouse, rat, calf and human. PMID: 6329429

• The localization of 2':3'-cyclic nucleotide 3'-phosphodiesterase in bovine cerebrum by immunofluorescence. PMID: 6318888

Immunohistochemistry (IHC)

• Expression of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) in amoeboid microglial cells (AMC) in developing rat brain from prenatal day 18 (E18) to postnatal day 10 (P10) was demonstrated by immunohistochemistry/immunofluorescence and immunoelectron microscopy both in vivo and in vitro, respectively. PMID: 16876328

• Immunohistochemical localization of 2',3'-cyclic nucleotide 3'-phosphodiesterase in adult bovine cerebrum and cerebellum. PMID: 2997644

• Immunohistochemical localization of 2',3'-cyclic nucleotide 3'-phosphodiesterase and myelin basic protein in the central nervous system of the jimpy and the normal mouse. PMID: 2579194

• Immunohistochemical techniques were utilized to localize the putative myelin enzyme 2':3'-cyclic nucleotide 3'-phosphodiesterase (CNP) in the central nervous system (CNS) of normal (+/+) and Shiverer (Shi/Shi) mice (Mus musculus). PMID: 2984337

• Immunohistochemical localization of 2', 3'-cyclic nucleotide 3'-phosphodiesterase in the central nervous system. PMID: 6261888