Supplementary Material for: Differential Expression of <b><i>SLC9A9</i></b> and Interacting Molecules in the Hippocampus of Rat Models for Attention Deficit/Hyperactivity Disorder

<i>SLC9A9</i> [solute carrier family 9, member 9, also known as Na⁺/H⁺ exchanger member 9 (NHE9)], has been implicated in human attention deficit/hyperactivity disorder (ADHD), autism, and rat studies of hyperactivity and inattentiveness. <i>SLC9A9</i> is a membrane protein that regulates the luminal pH of the recycling endosome. We recently reported the interactions of <i>SLC9A9</i> with two molecules: calcineurin homologous protein <i>(CHP)</i> and receptor for activated C-kinase 1 <i>(RACK1)</i>. We also reported two novel <i>SLC9A9</i> mutations and abnormal gene expression profiles in the brains of an inattentive type rat model of ADHD (WKY/NCrl rat). In this study, we further examined the expression and relationship of <i>SLC9A9</i> and 9 additional genes <i>(CHP, RACK1, CaM, PPP3R1, PPP1R10, PKCm, CaMKI, NR2B, PLCb1)</i> that may directly or indirectly interact with <i>SLC9A9</i> in the hippocampus of the WKY/NCrl rat and the spontaneously hypertensive rat (SHR) model of the combined type of ADHD. We found that the expression levels of these genes were significantly correlated, suggesting that they may be coregulated. Principal component analysis identified two main factors that accounted for 94% of the expression variance of the 10 genes. Significant differences were found for both factors across the 3 different rat strains. The two ADHD rat models (WKY/NCrl and SHR), although different from each other in adulthood, showed similar profiles in adolescence. Both models were significantly different from WKY/NHsd control rats at both ages. The expression abnormalities of each gene were evaluated and their roles in cell signaling processes such as calcium signaling and protein phosphorylation are discussed. Our results suggest that abnormalities in <i>SLC9A9</i>-mediated signaling pathways could contribute to the ADHD phenotype of two rat models (WKY/NCrl and SHR/NCrl), and that the perturbation of the <i>SLC9A9</i> network is age-dependent

Supplementary Material for: Characterization of a Novel Mutation in <b><i>SLC1A1 </i></b>Associated with Schizophrenia

We have recently described a hemi-deletion on chromosome 9p24.2 at the <i>SLC1A1</i> gene locus and its co-segregation with schizophrenia in an extended Palauan pedigree. This finding represents a point of convergence for several pathophysiological models of schizophrenia. The present report sought to characterize the biological consequences of this hemi-deletion. Dual luciferase assays demonstrated that the partially deleted allele (lacking exon 1 and the native promoter) can drive expression of a 5′-truncated <i>SLC1A1</i> using sequence upstream of exon 2 as a surrogate promoter. However, confocal microscopy and electrophysiological recordings demonstrate that the 5′-truncated <i>SLC1A1</i> lacks normal membrane localization and glutamate transport ability. To identify downstream consequences of the hemi-deletion, we first used a themed qRT-PCR array to compare expression of 84 GABA and glutamate genes in RNA from peripheral blood leukocytes in deletion carriers (n = 11) versus noncarriers (n = 8) as well as deletion carriers with psychosis (n = 5) versus those without (n = 3). Then, targeted RNA-Seq (TREx) was used to quantify expression of 375 genes associated with neuropsychiatric disorders in HEK293 cells subjected to either knockdown of <i>SLC1A1</i> or overexpression of full-length or 5′-truncated <i>SLC1A1</i>. Expression changes of several genes strongly implicated in schizophrenia pathophysiology were detected (e.g. <i>SLC1A2</i>,<i> SLC1A3</i>,<i> SLC1A6</i>,<i> SLC7A11</i>,<i> GRIN2A</i>,<i> GRIA1 </i>and<i> DLX1</i>)

Supplementary Material for: Analysis of Shared Haplotypes amongst Palauans Maps Loci for Psychotic Disorders to 4q28 and 5q23-q31

<p>To localize genetic variation affecting risk for psychotic disorders in the population of Palau, we genotyped DNA samples from 203 Palauan individuals diagnosed with psychotic disorders, broadly defined, and 125 control subjects using a genome-wide single nucleotide polymorphism array. Palau has unique features advantageous for this study: due to its population history, Palauans are substantially interrelated; affected individuals often, but not always, cluster in families; and we have essentially complete ascertainment of affected individuals. To localize risk variants to genomic regions, we evaluated long-shared haplotypes, ≥10 Mb, identifying clusters of affected individuals who share such haplotypes. This extensive sharing, typically identical by descent, was significantly greater in cases than population controls, even after controlling for relatedness. Several regions of the genome exhibited substantial excess of shared haplotypes for affected individuals, including 3p21, 3p12, 4q28, and 5q23-q31. Two of these regions, 4q28 and 5q23-q31, showed significant linkage by traditional LOD score analysis and could harbor variants of more sizeable risk for psychosis or a multiplicity of risk variants. The pattern of haplotype sharing in 4q28 highlights <i>PCDH10</i>, encoding a cadherin-related neuronal receptor, as possibly involved in risk.</p