0000000000278149
AUTHOR
Tim Tralau
showing 4 related works from this author
Sex-specific windows for high mRNA expression of DNA methyltransferases 1 and 3A and methyl-CpG-binding domain proteins 2 and 4 in human fetal gonads
2006
DNA methyltransferases (DNMTs) and 5-methyl-CpG-binding domain proteins (MBDs) are involved in the acquisition of parent-specific epigenetic modifications in human male and female germ cells. Reverse Northern blot analyses demonstrated sex-specific differences in mRNA expression for the maintenance DNMT1 and the de novo DNMT3A in developing testis and ovary. In fetal testis DNMT1 and DNMT3A expression peaked in mitotically arrested spermatogonia around 21 weeks gestation. In fetal ovary transcriptional upregulation of DNMT1 and DNMT3A occurred during a very brief period at 16 weeks gestation, when the oocytes proceeded through meiotic prophase. Fetal gonads showed several fold higher DNMT3A…
Expression ofDNMT3A transcripts and nucleolar localization of DNMT3A protein in human testicular and fibroblast cells suggest a role for de novo DNA …
2006
Transcriptional silencing during differentiation of human male germ cells and serum starvation of human fibroblasts is controlled by epigenetic mechanisms that involve de novo DNA methylation. It is associated with high expression of different transcripts of the DNA methyltransferase 3A (DNMT3A) gene that encode two isoforms with de novo methyltransferase activity and one without catalytic activity. Western blots revealed that DNMT3A protein (with catalytic domain) is present at low levels in several tissues and at increased levels in testicular cells and growth-arrested fibroblasts. Immunofluorescence experiments localized DNMT3A to discrete nucleolar foci in B spermatogonia and resting fi…
Epigenetic dysregulation in the developing Down syndrome cortex
2016
Using Illumina 450K arrays, 1.85% of all analyzed CpG sites were significantly hypermethylated and 0.31% hypomethylated in fetal Down syndrome (DS) cortex throughout the genome. The methylation changes on chromosome 21 appeared to be balanced between hypo- and hyper-methylation, whereas, consistent with prior reports, all other chromosomes showed 3–11 times more hyper- than hypo-methylated sites. Reduced NRSF/REST expression due to upregulation of DYRK1A (on chromosome 21q22.13) and methylation of REST binding sites during early developmental stages may contribute to this genome-wide excess of hypermethylated sites. Upregulation of DNMT3L (on chromosome 21q22.4) could lead to de novo methyl…
Congenital nephrosis, mesangial sclerosis, and distinct eye abnormalities with microcoria: An autosomal recessive syndrome
2004
We observed the occurrence of congenital nephrotic syndrome (CNS) and distinct ocular anomalies in two unrelated families. Eleven children from both families presented with a similar course of renal disease starting with nephrotic syndrome and renal failure prenatally or immediately after birth that resulted in death before the age of 2 months. Kidney histopathology showed diffuse mesangial sclerosis (DMS). Clinically obvious eye abnormalities were recognized in six of the eight patients in whom sufficient clinical data were available. Ocular anomalies included enlarged or large appearing corneae in some cases suggesting buphthalmos, and extremely narrow, nonreactive pupils (microcoria). Pa…