Ly6/neurotoxin 1 is a protein in humans that is encoded by the LYNX1 gene.  Alternatively spliced variants encoding different isoforms have been identified.
Function [ edit ]
This gene encodes a member of the Ly-6/
neurotoxin gene family, a group of lymphocyte antigens that attach to the cell surface by a glycosylphosphatidylinositol anchor and have a unique structure showing conserved 8-10 cysteine residues with a characteristic spacing pattern. Functional analysis indicates that this protein is not a ligand or neurotransmitter but has the capacity to enhance nicotinic acetylcholine receptor function in the presence of acetylcholine. This gene may also play a role in the pathogenesis of psoriasis vulgaris. 
The LYNX1 gene codes for a protein (Lynx1) that binds to
acetylcholine receptors in the brain. Lynx1 a member of the Ly6 superfamily of proteins that are capable of modulating neurotransmitter receptors.  
Lynx1 and Visual Plasticity [ edit ]
Transgenic mice without Lynx1 expression do not have a normal critical period of neuroplasticity in the visual cortex for development of ocular dominance columns. These mice show unusually rapid recovery from  amblyopia in adulthood indicating a role in reduction of synaptic plasticity during the normal expression of Lynx1 in adult brain. 
Lynx1 reduces adult visual cortex
plasticity by binding to nicotinic acetylcholine receptors (NAchR) and diminishing acetylcholine signaling. After the developmental  critical period and into adulthood, both Lynx1 mRNA and protein levels increase in the adult V1 and the lateral geniculate nucleus (LGN). Lynx1 and nAChR mRNAs are co-expressed in the LGN, as well as in  parvalbumin-positive GABAergic interneurons. After monocular deprivation during the  critical period to induce amblyopia, Lynx1 knock-out rat models spontaneously recovered normal visual acuity by reopening the closed eye. Similarly, an infusion of  physostigmine to increase acetylcholine signaling prompted recovery from amblyopia in wild type mice Inhibition of Lynx1 may be a possible therapeutic mechanism to prolong  synaptic plasticity of the visual cortex and improve binocular function of some amblyopes.
See also [ edit ]
Other Ly6 family proteins that are expressed in the brain:
Lynx2, LYPD6, LYPD6B and PSCA. 
References [ edit ]
^ "Human PubMed Reference:".
^ "Mouse PubMed Reference:".
^ a b "Entrez Gene: Ly6/neurotoxin 1".
^ a b c Miwa JM, Lester HA, Walz A (Aug 2012). "Optimizing cholinergic tone through lynx modulators of nicotinic receptors: implications for plasticity and nicotine addiction". Physiology. 27 (4): 187–99. doi: 10.1152/physiol.00002.2012. PMID 22875450.
^ Holford M, Auer S, Laqua M, Ibañez-Tallon I (2009). "Manipulating neuronal circuits with endogenous and recombinant cell-surface tethered modulators". Frontiers in Molecular Neuroscience. 2: 21. doi: 10.3389/neuro.02.021.2009. PMC . 2776481 PMID 19915728.
^ Higley MJ, Strittmatter SM (Nov 2010). "Neuroscience. Lynx for braking plasticity". Science. 330 (6008): 1189–90. doi: 10.1126/science.1198983. PMC . 3244692 PMID 21109660.
^ a b c d e Morishita H, Miwa JM, Heintz N, Hensch TK (Nov 2010). "Lynx1, a cholinergic brake, limits plasticity in adult visual cortex". Science. 330 (6008): 1238–40. doi: 10.1126/science.1195320. PMC . 3387538 PMID 21071629.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.