title: Neuropeptide Y (NPY): genetic variation in the human promoter alters glucocorticoid signaling, yielding increased NPY secretion and stress responses.
abstract: OBJECTIVE
  This study sought to understand whether genetic variation at the Neuropeptide Y (NPY) locus governs secretion and stress responses in vivo as well as NPY gene expression in sympathochromaffin cells.
  
  
  BACKGROUND
  The NPY is a potent pressor peptide co-released with catecholamines during stress by sympathetic axons. Genome-wide linkage on NPY secretion identified a LOD (logarithm of the odds ratio) peak spanning the NPY locus on chromosome 7p15.
  
  
  METHODS
  Our approach began with genomics (linkage and polymorphism determination), extended into NPY genetic control of heritable stress traits in twin pairs, established transcriptional mechanisms in transfected chromaffin cells, and concluded with observations on blood pressure (BP) in the population.
  
  
  RESULTS
  Systematic polymorphism tabulation at NPY (by re-sequencing across the locus: promoter, 4 exons, exon/intron borders, and untranslated regions; on 2n = 160 chromosomes of diverse biogeographic ancestries) identified 16 variants, of which 5 were common. We then studied healthy twin/sibling pairs (n = 399 individuals), typing 6 polymorphisms spanning the locus. Haplotype and single nucleotide polymorphism analyses indicated that proximal promoter variant ∇-880Δ (2-bp TG/-, Ins/Del, rs3037354) minor/Δ allele was associated with several heritable (h(2)) stress traits: higher NPY secretion (h(2) = 73 ± 4%) as well as greater BP response to environmental (cold) stress, and higher basal systemic vascular resistance. Association of ∇-880Δ and plasma NPY was replicated in an independent sample of 361 healthy young men, with consistent allelic effects; genetic variation at NPY also associated with plasma NPY in another independent series of 2,212 individuals derived from Australia twin pairs. Effects of allele -880Δ to increase NPY expression were directionally coordinate in vivo (on human traits) and in cells (transfected NPY promoter/luciferase reporter activity). Promoter -880Δ interrupts a novel glucocorticoid response element motif, an effect confirmed in chromaffin cells by site-directed mutagenesis on the transfected promoter, with differential glucocorticoid stimulation of the motif as well as alterations in electrophoretic mobility shifts. The same -880Δ allele also conferred risk for hypertension and accounted for approximately 4.5/approximately 2.1 mm Hg systolic BP/diastolic BP in a population sample from BP extremes.
  
  
  CONCLUSIONS
  We conclude that common genetic variation at the NPY locus, especially in proximal promoter ∇-880Δ, disrupts glucocorticoid signaling to influence NPY transcription and secretion, raising systemic vascular resistance and early heritable responses to environmental stress, eventuating in elevated resting BP in the population. The results point to new molecular strategies for probing autonomic control of the human circulation and ultimately susceptibility to and pathogenesis of cardiovascular and neuropsychiatric disease states.
authors.affiliation: Department of Medicine and Institute for Genomic Medicine, University of California at San Diego, San Diego, California, USA.
authors.forename: Kuixing
authors.initials: K
authors.lastname: Zhang
authors.forename: Fangwen
authors.initials: F
authors.lastname: Rao
authors.forename: Jose Pablo
authors.initials: JP
authors.lastname: Miramontes-Gonzalez
authors.forename: C Makena
authors.initials: CM
authors.lastname: Hightower
authors.forename: Brian
authors.initials: B
authors.lastname: Vaught
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Chen
authors.forename: Tiffany A
authors.initials: TA
authors.lastname: Greenwood
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Schork
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Manjula
authors.initials: M
authors.lastname: Mahata
authors.forename: Mats
authors.initials: M
authors.lastname: Stridsberg
authors.forename: Srikrishna
authors.initials: S
authors.lastname: Khandrika
authors.forename: Nilima
authors.initials: N
authors.lastname: Biswas
authors.forename: Maple M
authors.initials: MM
authors.lastname: Fung
authors.forename: Jill
authors.initials: J
authors.lastname: Waalen
authors.forename: Rita P
authors.initials: RP
authors.lastname: Middelberg
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Heath
authors.forename: Grant W
authors.initials: GW
authors.lastname: Montgomery
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Martin
authors.forename: John B
authors.initials: JB
authors.lastname: Whitfield
authors.forename: Dewleen G
authors.initials: DG
authors.lastname: Baker
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Schork
authors.forename: Caroline M
authors.initials: CM
authors.lastname: Nievergelt
authors.forename: Daniel T
authors.initials: DT
authors.lastname: O'Connor
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D004247:DNA / Q000235:genetics*; D024202:Electrophoretic Mobility Shift Assay; D005260:Female; D005786:Gene Expression Regulation; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009478:Neuropeptide Y / Q000096:biosynthesis / Q000235:genetics*; D011401:Promoter Regions, Genetic; D011965:Receptors, Glucocorticoid / Q000097:blood*; D015398:Signal Transduction; D013315:Stress, Psychological / Q000097:blood / Q000235:genetics*
chemical_list: D009478:Neuropeptide Y; D011965:Receptors, Glucocorticoid; D004247:DNA