Identification of a novel contactin‐associated transmembrane receptor with multiple domains implicated in protein–protein interactions

“Antibodies P6061 and P4344 directed to the intracellular region of Caspr or Caspr2, respectively, monoclonal antibody M275 directed against the extracellular domain of Caspr, as well as mouse serum that recognizes the extracellular region of Caspr2 have been previously described (Peles et al., 1997; Poliak et al., 199…”

“In animal cells, many GPI-anchored proteins are localized in plasma membrane microdomains where they associate with specific groups of transmembrane proteins (Peles et al., 1997; Muñiz and Riezman, 2000).”

“5) (Biogenesis; 1 : 1000); mouse monoclonal Downloaded from https://academic.oup.com/brain/article-abstract/128/5/1168/278531 by guest on 28 July 2018 and rabbit polyclonal antibodies to contactin-associated protein (Caspr) (Peles et al., 1997); mouse monoclonal anti-Kv1.”

“Furthermore, RPTPb expressed at the surface of glial cells binds to a cell recognition complex on neurons consisting of several proteins which include contactin, Caspr (also named paranodin) (34, 35 ), and Nr-CAM (40).”

“The paranodal junctions consist of a complex containing the axonal proteins Caspr (12) and contactin (13) and the glial isoform of neurofascin (14).”

“Rb pan Na channels 1:500 Vabnick et al., 1997 Rb Nav1.2 1:100 Caldwell et al., 2000 Rb Nav1.6 1:100 Caldwell et al., 2000 Rb Nav1.7 1:100 Caldwell et al., 2000 Rb Nav1.8 1:100 Caldwell et al., 2000 Rb Nav1.9 1:100 Fjell et al., 2000 Rb ankyrinG 1:100 Lambert et al., 1997 Rb Kv1.1 1:200 Alomone Labs, Jerusalem, Israel…”

“…al., 1993), NrCAM (Morales et al., 1993; Suter et al., 1995;Sensory neurons located in the dorsal root ganglia (DRG) Fitzli et al., 2000), RPTP /phosphacan (Milev et al., 1996;transmit different types of sensory information to the Peles et al., 1997), neurofascin (Volkmer et al., 1998),spinal cord.”

“Lateral cis interactions occur with the Ig superfamily transmembrane receptors Ng-CAM and Nr-CAM (Brümmendorf et al., 1993; Morales et al., 1993; Sakurai et al., 1997) and with Caspr (Peles et al., 1997).”

“In the latter case, Ntm, like other GPIanchored proteins, may associate with nonreceptor tyrosine kinases in glycosphingolipid-enriched membrane domains (Faivre-Sarrailh and Rougon, 1997; Henke et al., 1997) or promote outgrowth via cis interactions with neuronal transmembrane proteins ( Peles et al., 1997; Galbiati e…”

“…mice expressing deletion mutants of Caspr and Caspr2 lacking their 4.1B-binding sequence Caspr and Caspr2 interact with 4.1 proteins through a short sequence found in their cytoplasmic domain (Menegoz et al., 1997; Peles et al., 1997; Gollan et al., 2002; Denisenko-Nehrbass et al., 2003).”

“S6E) (Peles et al., 1997;Poliak et al., 2003; Traka et al., 2003).”

“These results suggest that Caspr serves as a “transmembrane scaffold” that stabilizes the Caspr/contactin adhesion complex at the paranodal junction by connecting it to cytoskeletal components within the axon.”

“…of caspr, neurofascin, and Nav channels was investigated after 22–28 days in vitro using antibodies directed against caspr, (1:1,000, anti-rabbit Peles et al., 1997), neurofascin (pan neurofascin 186 and 155, 1:1,000, anti-rabbit, Tait et al., 2000), and pan sodium channels (1:100, Nav, Sigma,…”

“The pres- ence of punctate Caspr staining, found exclusively at paranodes (Peles et al., 1997), was used as a surrogate measure of intact myelin (Arancibia- Carcamo et al., 2017; Etxeberria et al., 2016; Pedraza, Huang, & Colman, 2009).”

“The Caspr is another molecule that can be used to define the paranodal regions at the nodes (Einheber et al., 1997; Menegoz et al., 1997; Peles et al., 1997).”

“It was suggested that Caspr2 is also involved in the proper placement of ion channels along the axon, albeit through a different mechanism that involves its coupling to the channels by an intermediate PDZ-domain scaffolding protein (Peles and Salzer, 2000; Poliak et al., 1999).”

“…et al. Molecular Interactions of Neurofascin 1091 (Pesheva et al., 1993; Friedlander et al., 1994; Peles et al., 1995; Sakurai et al., 1997; Peles et al., 1997; Kunz et al., 1996; Rader et al., 1996; Suter et al., 1995; Buchstaller et al., 1996; Kuhn et al., 1991; Morales et al., 1993;…”

“Sodium channels are aggregated at the node of Ranvier, whereas Paranodin/Caspr, associated in cis with contactin on the axonal surface, is expressed at the paranode [27,28].”

“A number of candidate proteins have been identified that may be involved in the aggregation of sodium channels and in the formation of paranodal axoglial junctions (Kordeli et al., 1995; Lambert et al., 1997; Menegoz et al., 1997; Peles et al., 1997; Berghs et al., 2000; Tait et al., 2000; Boyle et al., 2001).”

“Caspr/paranodin Caspr, also known as paranodin, is a 190 kDa member of the neurexin superfamily of transmembrane proteins encoded on chromosome 17q21 [191,192].”

“…(a membrane skeleton protein) reportedly form a molecular complex at the vertebrate paranodal junction (Einheber et al., 1997; Menegoz et al., 1997; Peles et al., 1997; Arroyo and Scherer, 2000; Salzer, 2003), and at the invertebrate septate junctions, neurexin IV and coracle, which are homologous…”

“The AGSJs comprise three major components, contactin-associated protein (Caspr) and contactin (Cont) on the axonal side, which bind to each other in cis, and the 155-kDa isoform of Nfasc, Nfasc, on the glial side (Fig. 4A; Menegoz et al., 1997; Peles et al., 1997; Rios et al., 2000; Charles et al., 2002).”

“…CT, USA), polyclonal guinea pig Caspr [1 : 2000; generated against the same fusion protein as previously characterized anti-Caspr antibodies (Peles et al., 1997); the plasmid for the fusion protein was a kind gift of E. Peles, Weizmann Institute, Rehovot, Israel], monoclonal peripherin (1 :…”

“…Baumgartner et al., 1996; Gobron et al., 1996; Einheber et al., 1997; He and Tessier-Lavigne, 1997; Kitsukawa et al., 1997; Kolodkin et al., 1997; Peles et al., 1997; Marı́n et al., 2001) that has been described in the InterPro database to function in cell– cell adhesion (Apweiler et al.,…”

“Similar fusion proteins have been used to localize ligands in other studies of membrane bound receptors (Davis et al. 1994; Peles et al. 1997).”

“The first new component was identified by Poliak et al. (1999) and named Caspr2 based on its homology to the paranodal axoglial junction component contactin-associated protein (Caspr; also known as parano- Figure 2. din or NCP1; Einheber et al., 1997; Menegoz et al., 1997; Peles et al., 1997).”

“6 at nodes formed by Schwann cell remyelination, identified using the paranodal marker Caspr (Menegoz et al., 1997; Peles et al., 1997) in sections that were serial to sections labelled for P0.”

“…polyclonal anti-caspr (1:2000 IB) (Rasband et al., 2003), monoclonal anti-caspr IgG (1:400 IF) (Rasband and Trimmer, 2001), monoclonal anti-caspr IgM (neat IF) (Schafer et al., 2004), all generated against a GST fusion protein containing the entire cytoplasmic domain of caspr (Peles et al., 1997).”

“iTBS shortens nodes of Ranvier At the end of each internode, anchoring proteins expressed by the myelin loops, such as neurofascin 155, interact with the axonal proteins contactin and CASPR to form paranodes (Bhat et al., 2001; Charles et al., 2002; Klingseisen et al., 2019; Peles et al., 1997; Sherman et al., 2005).”

“Rabbit polyclonal antibodies against gliomedin (Eshed et al., 2007), Caspr (Peles et al., 1997), protein 4.1B (Gollan et al., 2002), neurofascin-155 (Poliak et al., 2001); rat antibody against Caspr (Feinberg et al., 2010); and mouse monoclonal antibodies against gliomedin (Eshed et al., 2005) and…”

“Several proteins involved in axoglial contacts have been identified [12,16], including paranodin [17], also known as Caspr [18].”

“Primary antibodies used in this study were rat anti-MBP (Millipore), rat antineurofilament (Millipore), rabbit anti-Caspr (Peles et al., 1997), rabbit anti-P0 (Wong and Filbin, 1994), rabbit antigliomedin (Eshed et al., 2005), rabbit anti-DRP2 (Sherman et al., 2001), rabbit anti–Oct-6 (Jaegle et…”

“, 2003)], or Caspr [1:500 (Peles et al., 1997)]; and mouse monoclonal antibodies against panNav channels (K58/35; 1:250; Sigma, St.”

“Caspr-1 belongs to the neurexin family and is composed of a discoidin domain, and several laminin-G and EGF-like modules (Menegoz et al., 1997; Peles et al., 1997; Figure 1).”

“The polyclonal and monoclonal anti-Caspr antibodies were a gift from Dr. Elior Peles and used at a dilution of 1:2500 and of 1:250, respectively ( Peles et al., 1997 ).”

“Contactin-6 also interacts with protein tyrosine phosphatase receptor-gamma (Peles et al., 1997; Bouyain and Watkins, 2010).”

“…experiments: rat antiNB2 (1A6) (Shimoda et al., 2012), rat anti-NB2 (1B10) (Toyoshima et al., 2009; Shimoda et al., 2012), rabbit anti-Caspr (Peles et al., 1997), rabbit anti-Caspr2 (Poliak et al., 1999), rabbit anti-Caspr3 (Spiegel et al., 2002), rabbit anti-Caspr4 (Spiegel et al., 2002),…”

“Rabbit polyclonal antibodies were made against a Caspr fusion protein kindly provided by Dr. E. Peles (Peles et al., 1997).”

“During myelination, the axonal proteins contactin and contactin-associated protein (caspr) interact with neurofascin 155 in the oligodendrocyte myelin loops (Peles et al., 1997; Bhat et al., 2001; Charles et al., 2002; Sherman et al., 2005) to form the paranodal junctions that stabilize the nodes.”

“…and axon occur at paranodal junctions via anchorage of the axonal cytoskeleton to the oligodendrocyte through interactions of several adhesion molecules, including Caspr and contactin (on the axon-side) with neurofascin 155 (on the oligodendrocyte side) (Peles et al. 1997; Charles et al. 2002).”

“1 binding domains and SH3 domains (28).”

“The following primary antibodies were used as well: mouse anti-Necl4ECD (NeuroMab), rat anti-MBP (Millipore Bioscience Research Reagents), rat and mouse antineurofilament (Millipore Bioscience Research Reagents), rabbit and mouse anti-Caspr (Peles et al., 1997; Gollan et al., 2002), Chick anti-P0 (Aves), mouse anti-tu…”

“2000); (ii) the paranodal domain characterized by a tripartite CAM complex (axonal Caspr and contactin and glial NF-155; Peles et al. 1997; Tait et al. 2000) that mediates the attachment of the myelin sheath to the axon (Fig.”

“The carbonic anhydrase domain and the FNIIIlike domain are required for binding to the Contactinprotein complexes (Peles et al., 1995; 1997; Sakurai et al., 1997).”

“A recent expression study showed that CNTNAP2 is consistently expressed in circuits involved in higher cortical functions, including language [Peles et al., 1997; Bellen et al., 1998; Poliak et al., 1999; Abrahams et al., 2007].”

“Northern analysis Total RNAs from cell lines, normal B cells and primary tumour specimens were size fractionated in 1% agalose/ formaldehyde gels and transferred to nylon membranes as described (Peles et al, 1997).”

“In this situation, a possible linker could be p190/Caspr, a molecule that has been recently cloned, expressed in ovary cells, and able to form ciscomplex with F3 ( Peles et al., 1997 ).”

“A 0334, 1:2000), mouse anti-APC (Calbio- chem, OP80, Clone CC1, San Diego, CA, 1:500), rabbit anti-Caspr (1:1000, [Peles et al., 1997]), mouse anti-Na Channel (1:75, [Rasband et al., 1999]).”

“Because both systems have signaling capabilities (Peles et al., 1997; Biederer et al., 2002), it would appear that, in addition to providing an adhesive interaction, these molecules can activate intracellular signaling cascades in both astrocyte and GnRH neurons (reviewed in Lomniczi & Ojeda, 2009)…”

“In animals, GPI anchors may interact directly with receptor proteins in the signaling of neural and brain development (Peles et al., 1997; Ferrando-Miguel et al., 2004).”

“Similar observations were done using antibodies against contactin (data not shown), which is associated in cis with paranodin in the axonal paranodal regions [28].”

“6 (Scn8a), rabbit-anti-Caspr2 (both Chemicon, Temecula, CA), rabbit-anti-Caspr (intracellular domain; Peles et al., 1997) and mouse-anti-Caspr (extracellular domain; Poliak et al., 1999).”

“, 2010), CASPR (Peles et al., 1997)) or prodced from hybridoma cells (anti-GalCer O1 (Sommer and Schachner, 1981)).”

“, 2001), consistent with CNTN1 and Caspr1 being mutually dependent for trafficking to the cell surface (Peles et al., 1997).”

“The paranodal complex comprises of the neurexin protein Caspr on the axon, and the Ig superfamily (IgSF) members contactin and neurofascin 155 on the axon and glial cell surface, respectively (Peles et al., 1997; Volkmer et al., 1998; Faivre-Sarrailh et al., 2000; Charles et al., 2002).”

“, 2004), and recognizes a band at 190 kDa on western blot from brain tissues (Peles et al., 1997).”

“…including Caspr, NrCAM, RPTPs/h, Cntn2 and Neurofascin 155 on neurons and glial cells (Buttiglione et al., 1998; Faivre-Sarrailh et al., 1999; Peles et al., 1995, 1997; Volkmer et al., 1998) and with the extracellular matrix molecules Tenascin-C and Tenascin-R (Pesheva et al., 1993; Rigato…”

“…995 a trimeric protein complex that includes the cell adhesion molecules contactin-associated protein (Caspr) and contactin in the axon membrane and oligodendroglial neurofascin155 kDa (NF-155) (Menegoz et al. 1997; Peles et al. 1997; Peles and Salzer 2000; Tait et al. 2000; Charles et al. 2002).”

“This junction is believed to form a barrier against the lateral diffusion of nodal Naþ channels.(18,19) Altogether, these results indicate that mutations of GLDN or CNTNAP, encoding essential components of the nodes of Ranvier and paranodes, respectively, lead to severe developmental defects of the PNS, leading to red…”

“(C and D) COS7 cells expressing the wildtype (WT) or MAG-S133R (S133R) proteins were immunolabelled using an antibody to MAG and to the endoplasmic reticulum marker proteins VAPB (C) or Caspr (D).”

“These include the axonal proteins contactin (Rios et al., 2000; Boyle et al., 2001) and the contactin-associated protein, Caspr (Einheber et al., 1997; Peles et al., 1997), which form a heteromeric complex at the paranodes (Rios et al., 2000).”