Renal gene expression in embryonic and newborn diabetic mice.
Several novel genes that are upregulated in diabetic kidneys have been identified. Recently, transforming growth factor beta driven secreted proteins, i.e., connective tissue growth factor and gremlin (bone morphogenetic protein 2), have been identified, and their expression has been correlated with the tissue changes seen in diabetic nephropathy in the adult population. However, there are very few studies reported in the literature that describe the gene expression in the diabetic state during embryonic and neonatal life. It is well known that exposure to glucose or its epimer, i.e., mannose, induces marked dysmorphogenesis of the embryonic metanephros in an organ culture system. These changes are associated with ATP depletion and marked apoptosis, suggesting an oxidant stress in the induction of dysmorphogenesis of the embryonic metanephros. In view of the glucose-induced changes in the fetal metanephros, a diabetic state was induced by the administration of streptozotocin during pregnancy, and newborn mouse kidneys were processed for suppression subtractive hybridization-PCR. In addition, a diabetic state was induced in newborn diabetic mice, and after 1 week their kidneys were harvested and subjected to representational difference analysis of cDNA. Four novel genes with upregulated mRNA expression were identified. They included: (1) a translocase inner mitochondrial membrane 44 that is involved in the ATP-dependent import of preproteins from the cytosol into the mitochondrial matrix; (2) a kidney-specific aldo-keto reductase that utilizes NADPH and NADH as cofactors in the reduction of aromatic aldehydes and aldohexoses; (3) Rap1b, a Ras-related small GTP-binding protein that behaves as a GTPase and cycles between GTP-bound (active) and GDP-bound (inactive) states associated with conformational change, and (4) a fusion protein of ubiquitin polypeptide and ribosomal protein L40 (UbA(52) or ubiquitin/60) that is intimately involved in the ubiquitin-dependent proteasome pathway related to the accelerated degradation of proteins under various stress conditions, such as those seen in patients with cancer and diabetes mellitus.
Wallner
Elisabeth I
EI
Department of Medicine, Northwestern University Medical School, 303 E Chicago Avenue, Chicago, IL 60611, USA.
Wada
Jun
J
Lin
Sun
S
Pan
Xiaomin
X
Reddy
Janaradan K
JK
Chugh
Sumant S
SS
Kanwar
Yashpal S
YS
D000429:Alcohol Oxidoreductases / Q000235:genetics; D000449:Aldehyde Reductase; D000074408:Aldo-Keto Reductases; D000595:Amino Acid Sequence; D000818:Animals; D000831:Animals, Newborn; D002352:Carrier Proteins / Q000235:genetics; D003928:Diabetic Nephropathies / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D007668:Kidney / Q000196:embryology* / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics; D051379:Mice; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D025801:Ubiquitin / Q000235:genetics; D020668:rap GTP-Binding Proteins / Q000235:genetics
D002352:Carrier Proteins; D008565:Membrane Proteins; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D024101:Mitochondrial Proteins; C489671:TIMM44 protein, human; C489672:Timm44 protein, mouse; D025801:Ubiquitin; D000429:Alcohol Oxidoreductases; D000074408:Aldo-Keto Reductases; D000449:Aldehyde Reductase; C000614209:AKR7A5 protein, mouse; C492136:Rap1b protein, mouse; D020668:rap GTP-Binding Proteins