Maternal-specific methylation of the imprinted mouse Igf2r locus identifies the expressed locus as carrying the imprinting signal

Cell. 1993 Apr 9;73(1):61-71. doi: 10.1016/0092-8674(93)90160-r.

Abstract

The mouse insulin-like growth factor type 2 receptor (Igf2r) is imprinted and expressed exclusively from the maternally inherited chromosome. To investigate whether methylation could function as the imprinting signal, we have cloned 130 kb from the Igf2r locus and searched for sequences methylated in a parental-specific manner. Two regions have been identified: region 1 contains the start of transcription and is methylated only on the silent paternal chromosome; region 2 is contained in an intron and is methylated only on the expressed maternal chromosome. Methylation of region 1 is acquired after fertilization, in contrast with the methylation of region 2, which is inherited from the female gamete. Methylation of region 2 may mark the maternal Igf2r locus in a manner that could act as an imprinting signal. These data suggest that the expressed locus carries a potential imprinting signal and imply that methylation is necessary for expression of the Igf2r gene.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Dosage Compensation, Genetic*
  • Female
  • Male
  • Methylation
  • Mice
  • Mice, Inbred BALB C
  • Molecular Sequence Data
  • Receptor, IGF Type 2 / genetics*
  • Regulatory Sequences, Nucleic Acid
  • Restriction Mapping
  • Sex Factors

Substances

  • Receptor, IGF Type 2

Associated data

  • GENBANK/L06445
  • GENBANK/L06446
  • GENBANK/M97300