Csf2 and Ptgs2 Epigenetic Dysregulation in Diabetes-prone Bicongenic B6.NODC11bxC1tb Mice.

In Type 1 diabetic (T1D) human monocytes, STAT5 aberrantly binds to epigenetic regulatory sites of two proinflammatory genes, CSF2 (encoding granulocyte-macrophage colony-stimulating factor) and PTGS2 (encoding prostaglandin synthase 2/cyclooxygenase 2). Bicongenic B6.NOD C11bxC1tb mice re-create this phenotype of T1D monocytes with only two nonobese diabetic (NOD) Idd subloci (130.8 Mb-149.7 Mb, of Idd5 on Chr 1 and 32.08-53.85 Mb of Idd4.3 on Chr11) on C57BL/6 genetic background. These two Idd loci interact through STAT5 binding at upstream regulatory regions affecting Csf2 (Chr 11) and Ptgs2 (Chr 1) expression. B6.NODC11bxC1tb mice exhibited hyperglycemia and immune destruction of pancreatic islets between 8 and 30 weeks of age, with 12%-22% penetrance. Thus, B6.NODC11bxC1tb mice embody NOD epigenetic dysregulation of gene expression in myeloid cells, and this defect appears to be sufficient to impart genetic susceptibility to diabetes in an otherwise genetically nonautoimmune mouse.

Novel TSHbeta subunit gene mutation causing congenital central hypothyroidism in a newborn male.

Newborn screening programs that use only high TSH levels as a marker for hypothyroidism may overlook neonates with congenital hypothyroidism (CH) due to TSH deficiency. We sought the cause of TSH deficiency in a neonate with low levels of thyroxine and TSH. The coding region of the TSHbeta gene was amplified and its sequence examined for mutations. Two mutations in exon 3 were identified: 1) a nucleotide deletion of T410 in codon 105 resulting in a frameshift in one allele, and 2) a previously unreported nucleotide deletion of T266 in codon 57, causing a frameshift and a premature stop at codon 62 in the other allele. We describe a compound heterozygous patient with TSHbeta mutations at codons 57 and 105 that interfered with a critical disulfide bond in the TSH molecule and caused CH. State screening programs that measure both T4 and TSH levels have the potential to detect newborns with congenital central hypothyroidism.

Molecular cloning and characterization of the mouse Acdp gene family.

BACKGROUND: We have recently cloned and characterized a novel gene family named ancient conserved domain protein (ACDP) in humans. To facilitate the functional study of this novel gene family, we have cloned and characterized Acdp, the mouse homologue of the human ACDP gene family. RESULTS: The four Acdp genes (Acdp1, Acdp2, Acdp3 and Acdp4) contain 3,631 bp, 3,244 bp, 2,684 bp and 2,743 bp of cDNA sequences, and encode deduced proteins of 951, 874, 713 and 771 amino acids, respectively. The mouse Acdp genes showed very strong homologies (>90%) in both nucleotide and amino acid sequences to their human counterparts. In addition, both nucleotide and amino acid sequences within the Ancient Conserved Domain (ACD) are highly conserved in many different taxonomic species. Particularly, Acdp proteins showed very strong AA homologies to the bacteria CorC protein (35% AA identity with 55% homology), which is involved in magnesium and cobalt efflux. The Acdp genes are widely expressed in all tissues tested except for Acdp1, which is only highly expressed in the brain with low levels of expression in kidney and testis. Immunostaining of Acdp1 in hippocampus neurons revealed a predominant localization on the plasma membrane. CONCLUSION: The Acdp genes are evolutionarily conserved in diverse species and ubiquitously expressed throughout development and adult tissues suggesting that Acdp may be an essential gene. Acdp showed strong homology to bacteria CorC protein and predominantly localized on the plasma membrane. These results suggest that Acdp is probably a family of proteins involved in ion transport in mammalian cells

Microarray analysis of gene expression in the kidneys of new- and post-onset diabetic NOD mice.

We profiled the expression of 5,760 clones from a kidney subtraction library in the kidneys of three groups of NOD mice: nondiabetic, new-onset, and long-term diabetic. A total of 27 genes had lower expression and 1 gene (Gpx3) had higher expression in the new-onset diabetic mice compared with nondiabetic control NOD mice (P < 0.001). Similarly, 19 of the above 27 genes and 7 additional genes had higher expression and the Gpx3 gene had lower expression in long-term diabetic mice compared with controls (P < 0.001). Interestingly, only three genes may be different between new-onset and long-term diabetic mice (P < 0.0004). These genes are from diverse functional groups, including oxidative phosphorylation, free radical neutralization, channels, pumps, lipid processing, transcription and translation machinery, protein trafficking, constitutive protein processing, and immune function. The majority of these genes fall into four signaling pathways: insulin, transforming growth factor-beta, tumor necrosis factor-alpha, and peroxisome proliferator-activated receptor. The most significant expression change was found for the stearoyl-coenzyme A desaturase 1 (SCD1) gene (P < 10(-7)). The lower expression levels of the SCD1 gene in both diabetic groups compared with controls were further confirmed by Northern blot analysis and immunohistochemistry.

High resolution mapping and mutation analyses of candidate genes in the urofacial syndrome (UFS) critical region.

The urofacial (Ochoa) syndrome (UFS) characterized by congenital obstructive uropathy and abnormal facial expression is a rare disorder caused by a single recessive disease gene. Our previous studies using homozygosity mapping have located the UFS gene to a genomic interval of approximately 360 kb on chromosome 10q23-10q24. In this study, we have constructed a genomic sequence map covering the entire UFS interval and narrowed the disease interval to a genomic region of 220 kb that harbor the newly identified ACDP1 gene in addition to part of the GOT1 gene which has already been excluded as a candidate for UFS. Extensive search for mutations in the coding region, the 5' and 3' untranslated regions, the promoter region, and the exon/intron junctions failed to identify a pathogenic mutation in UFS patients. Furthermore, our analyses indicated that the same gene on chromosome 10q is responsible for all UFS patients from multiple ethnic groups.

Molecular cloning and characterization of a novel gene family of four ancient conserved domain proteins (ACDP).

We have recently cloned four novel human genes that encode the ancient conserved domain proteins (ACDP). The full-length cDNA sequence of ACDP1 consists of 5898 bp and encodes a predicted protein of 951 amino acids (AA). The transcript for ACDP2 has 4058 bp of cDNA sequence, encoding a protein of 875 AA. ACDP3 contains 3113 bp of cDNA sequence and encodes a putative protein of 707 AA. ACDP4 contains 4765 bp of cDNA sequence and encodes a protein of 775 AA. The ACDP genes belong to a highly conserved new gene family. The conserved region showed 62.8% of nucleotide sequence identity, and 65.5% of AA identity with 92% of AA homologies among ACDP members. The conserved domain is also found in genes from evolutionarily divergent species from bacteria, yeast, Caenorhabditis elegans, and Drosophila melanogaster to mammals. All ACDP genes except ACDP1 have a ubiquitous expression pattern while ACDP1 expression is restricted to the brain and testis. Immunofluorescence staining of premeablized HeLa cells showed that ACDP proteins are predominantly localized in the nucleus. Sequence homology analyses revealed AA property and structural homologies between the ACD domain and cyclin molecules.