title: Isolation and differential expression of two isoforms of the ROBO2/Robo2 axon guidance receptor gene in humans and mice.
abstract: Expression of Robo receptor molecules is important for axon guidance across the midline of the mammalian central nervous system. Here we describe novel isoform a of human ROBO2, which is initially strongly expressed in the fetal human brain but thereafter only weakly expressed in adult brain and a few other tissues. The known isoform b of ROBO2 shows a more or less ubiquitous expression pattern, suggesting diverse functional roles. The genomic structure and distinct expression patterns of Robo2a and Robo2b have been conserved in the mouse, but in contrast to human ROBO2a mouse Robo2a is also abundant in adult brain. Exons 1 and 2 of human ROBO2a lie in an inherently unstable DNA segment at human chromosome 3p12.3 that is associated with segmental duplications, independent chromosome rearrangements during primate evolution, and homozygous deletion and loss of heterozygosity in various human cancers. The 5' end of mouse Robo2a lies in a <150-kb DNA segment of break in synteny between mouse chromosome 16C3.1 and the human genome.
authors.affiliation: Institute for Human Genetics, Mainz University School of Medicine, Langenbeckstrasse 1, Building 601, 55131 Mainz, Germany.
authors.forename: Ying
authors.initials: Y
authors.lastname: Yue
authors.affiliation: Institute for Human Genetics, Mainz University School of Medicine, Langenbeckstrasse 1, Building 601, 55131 Mainz, Germany.
authors.forename: Bärbel
authors.initials: B
authors.lastname: Grossmann
authors.affiliation: Institute for Human Genetics, Mainz University School of Medicine, Langenbeckstrasse 1, Building 601, 55131 Mainz, Germany.
authors.forename: Danuta
authors.initials: D
authors.lastname: Galetzka
authors.affiliation: Institute for Human Genetics, Mainz University School of Medicine, Langenbeckstrasse 1, Building 601, 55131 Mainz, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Zechner
authors.affiliation: Institute for Human Genetics, Mainz University School of Medicine, Langenbeckstrasse 1, Building 601, 55131 Mainz, Germany. Electronic address: haaf@humgen.klinik.uni-mainz.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Haaf
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000196:embryology / Q000378:metabolism; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics; D033481:Chromosomes, Mammalian / Q000235:genetics; D005091:Exons / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000235:genetics* / Q000378:metabolism; D011971:Receptors, Immunologic / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000097905:Roundabout Proteins
chemical_list: D020033:Protein Isoforms; D011971:Receptors, Immunologic; C498890:ROBO2 protein, human; D000097905:Roundabout Proteins; C498888:Robo2 protein, mouse