A BROAD BEAN CDNA CLONE ENCODING A DNA-BINDING PROTEIN RESEMBLING MAMMALIAN CREB IN ITS SEQUENCE SPECIFICITY AND DNA METHYLATION SENSITIVITY
GENE
Authors: EHRLICH, KC; CARY, JW; EHRLICH, M
Abstract
A plant cDNA has been cloned that encodes a DNA-binding protein displaying a nucleotide (nt) sequence specificity similar to that of the mammalian cyclic AMP response element-binding protein/activating transcription factor (CREB/ATF) family of mammalian proteins. This cDNA was cloned in Escherichia coli from a broad bean (Vicia faba) cDNA expression library using a recognition site probe. The deduced amino acid (aa) sequence of the recombinant cDNA-encoded protein, called VBP1, has a basic region adjacent to a leucine zipper motif, of the type seen in the DNA-binding domains of many eukaryotic DNA-binding proteins, including mammalian CREB/ATF. Although this aa sequence has homology to regions of deduced aa sequences of other cloned plant cDNAs, it is distinct in both the derived primary structure and in its nt sequence specificity. VBP1, as well as proteins in nuclear extracts of V. faba with similar nt sequence specificity, have their binding to DNA suppressed more than tenfold by cytosine methylation at the CREB/ATF consensus sequence.
Disease-dependent Differently Methylated Regions (D-DMRs) of DNA are Enriched on the X Chromosome in Uterine Leiomyoma
JOURNAL OF REPRODUCTION AND DEVELOPMENT
Authors: Maekawa, Ryo; Yagi, Shintaro; Ohgane, Jun; Yamagata, Yoshiaki; Asada, Hiromi; Tamura, Isao; Sugino, Norihiro; Shiota, Kunio
Abstract
Uterine leiomyoma is the most common benign tumor in women. Although responsible gene mutations have not been found in leiomyomas, they represent a progressive disease with irreversible symptoms. To characterize epigenetic features of uterine leiomyomas, the DNA methylation status of a paired sample of leiomyoma and normal myometrium was subjected to a microarray-based DNA methylation analysis with restriction tag-mediated amplification (D-REAM). in the leiomyoma, we identified an aberrant DNA methylation status for 463 hypomethylated and 318 hypermethylated genes. Although these changes occurred on all chromosomes, aberrantly hypomethylated genes were preferentially located on the X chromosome. Using paired samples of normal myometrium and leiomyoma from 6 hysterectomy patients, methylation-sensitive quantitative real-time PCR revealed 14 shared X chromosome genes with an abnormal DNA hypomethylation status (FAM9A, CPXCR1, CXORF45, TAF1, NXF5, VBP1, GABRE, DDX53, FHL1, BRCC3, DMD, GJB1, AP1S2 and PCDH11X) and one hypermethylated locus (HDAC8). Expression of XIST, which is involved in X chromosome inactivation, was equivalent in the normal myometrium and leiomyoma, indicating that the epigenetic abnormality on the X chromosome did not result from aberration of XIST gene expression. Based on these data, a unique epigenetic signature for uterine leiomyomas has emerged. The 14 hypomethylated and one hypermethylated loci provide valuable biomarkers for understanding the molecular pathogenesis of leiomyoma.