title: Laminets: laminin- and netrin-related genes expressed in distinct neuronal subsets.
abstract: Laminins and netrins are families of related secreted proteins known to play critical roles in guiding the growth of peripheral and central axons, respectively. Here we report the identification of two novel cell surface glycoproteins that we name laminets because they resemble both laminins and netrins. Laminet-1 and -2 are selectively expressed in neurons, each in a distinct subset that includes populations in forebrain, midbrain, hindbrain, spinal cord, and spinal ganglia. In several forebrain regions, including main relays of the central olfactory pathway, laminet-1 and -2 are expressed in nonoverlapping neuronal subsets. Both laminets are subject to alternative splicing which, in the case of laminet-1, generates at least 10 distinct isoforms, each of which contains a unique combination of potential binding sites for ligands or counterreceptors. Their complex patterns of distribution and isoform diversity, along with their homology to known axon guidance molecules, suggest that laminets contribute to the patterning of neuronal connections.
authors.affiliation: Department of Anatomy and Neurobiology, Washington University Medical School, St. Louis, Missouri 63110, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yin
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Miner
authors.forename: Joshua R
authors.initials: JR
authors.lastname: Sanes
mesh_terms: D017398:Alternative Splicing / Q000235:genetics; D000818:Animals; D001921:Brain / Q000196:embryology; D001923:Brain Chemistry / Q000235:genetics*; D019143:Evolution, Molecular; D058851:GPI-Linked Proteins; D018507:Gene Expression Regulation, Developmental; D006023:Glycoproteins / Q000235:genetics* / Q000378:metabolism; D006031:Glycosylation; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics; D000075385:Netrins; D009474:Neurons / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D017386:Sequence Homology, Amino Acid
chemical_list: D058851:GPI-Linked Proteins; D006023:Glycoproteins; C463082:NTNG1 protein, human; C463083:NTNG2 protein, human; D009419:Nerve Tissue Proteins; D000075385:Netrins; C456263:Ntng2 protein, mouse; D012333:RNA, Messenger; C463080:laminet-1, mouse; C413653:netrin-G1