Biomaterial Database

Methylated DNA sequences in genomic imprinting. 2000

J R Mann, and P E Szabó, and M R Reed, and J Singer-Sam

Division of Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010-3011, USA.

Genomic imprinting is a special form of epigenetic system that determines the parent-of-origin-specific, or monoallelic, expression of a small number of genes, termed "imprinted" genes. Considerable sequence and methylation analysis of imprinted genes has revealed a common theme: Regions of allele-specific methylation inherited from the gametes, or primary differentially methylated regions (DMRs), are associated with CpG islands and repeat elements, and this overall structure suggests functional significance. For at least three imprinted genes the sequence of the primary DMR constitutes an element able to regulate gene activity in cis--a chromatin insulator and a promoter of an antisense transcript. In these cases the unique feature of imprinting appears to be in the ability to switch the regulatory capacity of these elements on or off by the absence or presence of inherited methylation. Increasing evidence therefore suggests that genomic imprinting for at least some genes constitutes the regulation of gene regulatory elements by methylation. An important challenge now is to determine how the differential methylation of primary DMR sequences is established in the germ line. If methylation is the primary imprint, then the processes establishing it are the primary imprinting mechanisms. Trans-acting factors that are expressed in one sex of germ line and not the other are likely to be involved, and their ability to methylate may be mediated through repeat elements associated with the sequence of primary DMRs.

UI	MeSH Term	Description	Entries
D007335	Insulin-Like Growth Factor II	A well-characterized neutral peptide believed to be secreted by the LIVER and to circulate in the BLOOD. It has growth-regulating, insulin-like and mitogenic activities. The growth factor has a major, but not absolute, dependence on SOMATOTROPIN. It is believed to be a major fetal growth factor in contrast to INSULIN-LIKE GROWTH FACTOR I, which is a major growth factor in adults.	IGF-II,Multiplication-Stimulating Activity,Somatomedin MSA,IGF-2,Insulin Like Growth Factor II,Insulin-Like Somatomedin Peptide II,Multiplication-Stimulating Factor,Somatomedin A,Factor, Multiplication-Stimulating,Insulin Like Somatomedin Peptide II,Multiplication Stimulating Activity,Multiplication Stimulating Factor
D011218	Prader-Willi Syndrome	An autosomal dominant disorder caused by deletion of the proximal long arm of the paternal chromosome 15 (15q11-q13) or by inheritance of both of the pair of chromosomes 15 from the mother (UNIPARENTAL DISOMY) which are imprinted (GENETIC IMPRINTING) and hence silenced. Clinical manifestations include MENTAL RETARDATION; MUSCULAR HYPOTONIA; HYPERPHAGIA; OBESITY; short stature; HYPOGONADISM; STRABISMUS; and HYPERSOMNOLENCE. (Menkes, Textbook of Child Neurology, 5th ed, p229)	Labhart-Willi Syndrome,Royer Syndrome,Labhart-Willi-Prader-Fanconi Syndrome,Prader Labhart Willi Syndrome,Prader-Labhart-Willi Syndrome,Royer's Syndrome,Willi-Prader Syndrome,Labhart Willi Prader Fanconi Syndrome,Labhart Willi Syndrome,Prader Willi Syndrome,Royers Syndrome,Syndrome, Labhart-Willi,Syndrome, Labhart-Willi-Prader-Fanconi,Syndrome, Prader-Labhart-Willi,Syndrome, Prader-Willi,Syndrome, Royer,Syndrome, Royer's,Syndrome, Willi-Prader,Willi Prader Syndrome
D005854	Germ Cells	The reproductive cells in multicellular organisms at various stages during GAMETOGENESIS.	Gamete,Gametes,Germ-Line Cells,Germ Line,Cell, Germ,Cell, Germ-Line,Cells, Germ,Cells, Germ-Line,Germ Cell,Germ Line Cells,Germ Lines,Germ-Line Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000483	Alleles	Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.	Allelomorphs,Allele,Allelomorph
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D017204	Angelman Syndrome	A syndrome characterized by multiple abnormalities, MENTAL RETARDATION, and movement disorders. Present usually are skull and other abnormalities, frequent infantile spasms (SPASMS, INFANTILE); easily provoked and prolonged paroxysms of laughter (hence "happy"); jerky puppetlike movements (hence "puppet"); continuous tongue protrusion; motor retardation; ATAXIA; MUSCLE HYPOTONIA; and a peculiar facies. It is associated with maternal deletions of chromosome 15q11-13 and other genetic abnormalities. (From Am J Med Genet 1998 Dec 4;80(4):385-90; Hum Mol Genet 1999 Jan;8(1):129-35)	Happy Puppet Syndrome,Puppet Children,Children, Puppet,Syndrome, Angelman,Syndrome, Happy Puppet
D062085	RNA, Long Noncoding	A class of untranslated RNA molecules that are typically greater than 200 nucleotides in length and do not code for proteins. Members of this class have been found to play roles in transcriptional regulation, post-transcriptional processing, CHROMATIN REMODELING, and in the epigenetic control of chromatin.	LincRNA,RNA, Long Untranslated,LINC RNA,LincRNAs,Long Intergenic Non-Protein Coding RNA,Long Non-Coding RNA,Long Non-Protein-Coding RNA,Long Noncoding RNA,Long ncRNA,Long ncRNAs,RNA, Long Non-Translated,lncRNA,Long Intergenic Non Protein Coding RNA,Long Non Coding RNA,Long Non Protein Coding RNA,Long Non-Translated RNA,Long Untranslated RNA,Non-Coding RNA, Long,Non-Protein-Coding RNA, Long,Non-Translated RNA, Long,Noncoding RNA, Long,RNA, Long Non Translated,RNA, Long Non-Coding,RNA, Long Non-Protein-Coding,Untranslated RNA, Long,ncRNA, Long,ncRNAs, Long
D018392	Genomic Imprinting	The variable phenotypic expression of a GENE depending on whether it is of paternal or maternal origin, which is a function of the DNA METHYLATION pattern. Imprinted regions are observed to be more methylated and less transcriptionally active. (Segen, Dictionary of Modern Medicine, 1992)	Genetic Imprinting,Parental Imprinting,Imprinting, Genetic,Imprinting, Genomic,Imprinting, Parental
D019175	DNA Methylation	Addition of methyl groups to DNA. DNA methyltransferases (DNA methylases) perform this reaction using S-ADENOSYLMETHIONINE as the methyl group donor.	DNA Methylations,Methylation, DNA,Methylations, DNA