Geno-transcriptomic dissection of proteinuria in the uninephrectomized rat uncovers a molecular complexity with sexual dimorphism. Physiol Genomics 2010 Nov 29;42A(4):301-16
Date
09/30/2010Pubmed ID
20876844DOI
10.1152/physiolgenomics.00149.2010Scopus ID
2-s2.0-78649736609 (requires institutional sign-in at Scopus site) 7 CitationsAbstract
Investigation of proteinuria, whose pathophysiology remains incompletely understood, is confounded by differences in the phenotype between males and females. We initiated a sex-specific geno-transcriptomic dissection of proteinuria in uninephrectomized male and female Sabra rats that spontaneously develop focal and segmental glomerulosclerosis, testing the hypothesis that different mechanisms might underlie the pathophysiology of proteinuria between the sexes. In the genomic arm, we scanned the genome of 136 male and 111 female uninephrectomized F2 populations derived from crosses between SBH/y and SBN/y. In males, we identified proteinuria-related quantitative trait loci (QTLs) on RNO2 and 20 and protective QTLs on RNO6 and 9. In females, we detected proteinuria-related QTLs on RNO11, 13, and 20. The only QTL overlap between the sexes was on RNO20. Using consomic strains, we confirmed the functional significance of this QTL in both sexes. In the transcriptomic arm, we searched on a genomewide scale for genes that were differentially expressed in kidneys of SBH/y and SBN/y with and without uninephrectomy. These studies identified within each sex differentially expressed genes of relevance to proteinuria. Integrating genomics with transcriptomics, we identified differentially expressed genes that mapped within the boundaries of the proteinuria-related QTLs, singling out 24 transcripts in males and 30 in females, only 4 of which (Tubb5, Ubd, Psmb8, and C2) were common to both sexes. Data mining revealed that these transcripts are involved in multiple molecular mechanisms, including immunity, inflammation, apoptosis, matrix deposition, and protease activity, with no single molecular pathway predominating in either sex. These results suggest that the pathophysiology of proteinuria is highly complex and that some of the underlying mechanisms are shared between the sexes, while others are sex specific and may account for the difference in the proteinuric phenotype between males and females.
Author List
Yagil Y, Hessner M, Schulz H, Gosele C, Lebedev L, Barkalifa R, Sapojnikov M, Hubner N, Yagil CAuthor
Martin J. Hessner PhD Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsCluster Analysis
Female
Gene Expression Profiling
Male
Nephrectomy
Phenotype
Proteinuria
Quantitative Trait Loci
Rats
Sex Characteristics