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Publication Abstract from PubMed

Contactins (CNTN) are neural cell adhesion molecules that encode axon-target specificity during the patterning of the vertebrate visual and olfactory systems. Because CNTNs are tethered to the plasma membrane by a glycosylphosphatidylinositol anchor, they lack an intracellular region to communicate across the membrane. Instead, they form co-receptor complexes with distinct transmembrane proteins to transmit signals inside the cell. In particular, a complex of CNTN4 and amyloid precursor protein (APP) is known to guide the assembly of specific circuits in the visual system. Here, using in situ hybridization in zebrafish embryos, we show that CNTN4, CNTN5, and the APP homologues APLP1 and APLP2 are expressed in olfactory pits, suggesting that these receptors may also function together in the organization of olfactory tissues. Furthermore, we use biochemical and structural approaches to characterize interactions between members of these two receptor families. In particular, APP and APLP1 interact with CNTN3-5, while APLP2 only binds to CNTN4 and 5. Finally, structural analyses of five CNTN/amyloid pairs indicate that these proteins interact through a conserved interface involving the second fibronectin type III repeat of CNTNs and the copper-binding domain of amyloid proteins. Overall, this work sets the stage for analyzing CNTN/amyloid-mediated connectivity in vertebrate sensory circuits.

Members of the vertebrate contactin and amyloid precursor protein families interact through a conserved interface.,Karuppan SJ, Vogt A, Fischer Z, Ladutska A, Swiastyn J, McGraw HF, Bouyain S J Biol Chem. 2021 Dec 24:101541. doi: 10.1016/j.jbc.2021.101541. PMID:34958801^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.