title: Expression of fourteen novel obesity-related genes in Zucker diabetic fatty rats.
abstract: BACKGROUND
  Genome-wide association studies (GWAS) are useful to reveal an association between single nucleotide polymorphisms and different measures of obesity. A multitude of new loci has recently been reported, but the exact function of most of the according genes is not known. The aim of our study was to start elucidating the function of some of these genes.
  
  
  METHODS
  We performed an expression analysis of fourteen genes, namely BDNF, ETV5, FAIM2, FTO, GNPDA2, KCTD15, LYPLAL1, MCR4, MTCH2, NEGR1, NRXN3, TMEM18, SEC16B and TFAP2B, via real-time RT-PCR in adipose tissue of the kidney capsule, the mesenterium and subcutaneum as well as the hypothalamus of obese Zucker diabetic fatty (ZDF) and Zucker lean (ZL) rats at an age of 22 weeks.
  
  
  RESULTS
  All of our target genes except for SEC16B showed the highest expression in the hypothalamus. This suggests a critical role of these obesity-related genes in the central regulation of energy balance. Interestingly, the expression pattern in the hypothalamus showed no differences between obese ZDF and lean ZL rats. However, LYPLAL1, TFAP2B, SEC16B and FAIM2 were significantly lower expressed in the kidney fat of ZDF than ZL rats. NEGR1 was even lower expressed in subcutaneous and mesenterial fat, while MTCH2 was higher expressed in the subcutaneous and mesenterial fat of ZDF rats.
  
  
  CONCLUSIONS
  The expression pattern of the investigated obesity genes implies for most of them a role in the central regulation of energy balance, but for some also a role in the adipose tissue itself. For the development of the ZDF phenotype peripheral rather than central mechanisms of the investigated genes seem to be relevant.
authors.affiliation: Klinik und Poliklinik für Innere Medizin II, University of Regensburg, Regensburg, Germany. peterm.schmid@ukr.de
authors.forename: Peter M
authors.initials: PM
authors.lastname: Schmid
authors.forename: Iris
authors.initials: I
authors.lastname: Heid
authors.forename: Christa
authors.initials: C
authors.lastname: Buechler
authors.forename: Andreas
authors.initials: A
authors.lastname: Steege
authors.forename: Markus
authors.initials: M
authors.lastname: Resch
authors.forename: Christoph
authors.initials: C
authors.lastname: Birner
authors.forename: Dierk H
authors.initials: DH
authors.lastname: Endemann
authors.forename: Guenter A
authors.initials: GA
authors.lastname: Riegger
authors.forename: Andreas
authors.initials: A
authors.lastname: Luchner
mesh_terms: D050153:Abdominal Fat / Q000378:metabolism; D000818:Animals; D003920:Diabetes Mellitus / Q000235:genetics* / Q000378:metabolism; D004195:Disease Models, Animal; D004734:Energy Metabolism / Q000235:genetics; D020869:Gene Expression Profiling / Q000379:methods; D005786:Gene Expression Regulation; D005838:Genotype; D007031:Hypothalamus / Q000378:metabolism; D008297:Male; D009765:Obesity / Q000150:complications / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D051381:Rats; D011924:Rats, Zucker; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050151:Subcutaneous Fat / Q000378:metabolism