Assignment of solute carrier family 2 (facilitated glucose transporter), members <i>SLC2A2</i>, <i>SLC2A3</i>, <i>SLC2A5</i>, <i>SLC2A8</i> and <i>SLC2A12</i> to porcine chromosomes by somatic cell and radiation hybrid panel mapping (Brief report)

The transport of glucose plays an important role in cellular glucose homeostasis and metabolism [1]. Due to the hydrophilic character of glucose, the transport of glucose in and out of cells requires specific carrier proteins. The mammalian facilitative glucose transport family, which contains the energy-independent transporters (gene symbol SLC2A, protein symbol GLUT), catalyzes the entry of glucose into mammalian cells by facilitative diffusion down a concentration gradient. Thirteen members of mammalian GLUT family have been now characterized [1]. In swine, the chromosomal locations for the five genes (SLC2A2, SLC2A3, SLC2A5, SLC2A8 and SLC2A12) have not yet been determined. In this study, as the first step to better understand of the roles of these GLUTs in pigs which could subsequently be beneficial for pig production, we report the mapping of the five genes using both porcine somatic cell hybrid panel (INRA-SCHP) and radiation hybrid panel (IMpRH).

Characterization of Nonfunctional V1R-like Pheromone Receptor Sequences in Human

The vomeronasal organ (VNO) or Jacobson's organ is responsible in terrestrial vertebrates for the sensory perception of pheromones, chemicals that elicit stereotyped behaviors among individuals of the same species. Pheromone-induced behaviors and a functional VNO have been described in a number of mammals, but the existence of this sensory system in human is still debated. Recently, two nonhomologous gene families, V1R and V2R, encoding pheromone receptors have been identified in rat. These receptors belong to the seven-transmembrane domain G-protein-coupled receptor superfamily. We sought to characterize V1R-like genes in the human genome. We have identified seven different human sequences by PCR and library screening with rodent sequences. These human sequences exhibit characteristic features of V1R receptors and show 52%–59% of amino acid sequence identity with the rat sequences. Using PCR on a monochromosomal somatic cell hybrid panel and/or FISH, we demonstrate that these V1R-like sequences are distributed on chromosomes 7, 16, 20, 13, 14, 15, 21, and 22 and possibly on additional chromosomes. One sequence hybridizes to pericentromeric locations on all the acrocentric chromosomes (13, 14, 15, 21, and 22). All of the seven V1R-like sequences analyzed show interrupted reading frames, indicating that they represent nonfunctional pseudogenes. The preponderence of pseudogenes among human V1R sequences and the striking anatomical differences between rodent and human VNO raise the possibility that humans may have lost the V1R/VNO-mediated sensory functions of rodents.[Sequence data from this article have been deposited with the DDBJ/EMBL/GenBank Data Libraries under accession nos. U73852–73853 andAF253312–253316.]

Isolation and chromosomal mapping of human glycogen synthase kinase-3 α and -3β encoding genes

Glycogen synthase kinase-3 (GSK-3) is a serine-threonine kinase that exists as two isoforms, α and β, encoded by separate genes. Phosphorylation targets include a variety of cytoplasmic and nuclear proteins. Recent studies found that neurofilaments, amyloid precursor protein, and tau proteins are substrates of GSK-3 and that aberrant phosphorylation of these proteins is implicated in pathologies of the nervous system. To analyse the organisation of these two genes, a YAC library was screened by polymerase chain reaction, using primers specific for human GSK-3α and GSK-3β cDNA. Two clones, 220 and 285 kb in size, containing the complete GSK-3α coding sequence, and two clones, 365 and 285 kb in size, containing the 5 coding sequence of GSK-3β, were isolated. By somatic cell hybrid panel DNA amplification and radiation hybrid mapping, GSK-3α was found to be located at 19q13.2. On the other hand, by somatic cell hybrid panel DNA amplification and fluorescence in situ hybridisation using the 285-kb YAC clone, GSK-3β was mapped to 3q13.3.Key words: Alzheimer's disease, fluorescence in situ hybridisation, glycogen synthase kinase, neurodegeneration, radiation hybrid mapping, yeast artificial chromosome.