title: LINE1 family member is negative regulator of HLA-G expression.
abstract: Class Ia molecules of human leucocyte antigen (HLA-A, -B and -C) are widely expressed and play a central role in the immune system by presenting peptides derived from the lumen of the endoplasmic reticulum. In contrast, class Ib molecules such as HLA-G serve novel functions. The distribution of HLA-G is mostly limited to foetal trophoblastic tissues and some tumour tissues. The mechanism required for the tissue-specific regulation of the HLA-G gene has not been well understood. Here, we investigated the genomic regulation of HLA-G by manipulating one copy of a genomic DNA fragment on a human artificial chromosome. We identified a potential negative regulator of gene expression in a sequence upstream of HLA-G that overlapped with the long interspersed element (LINE1); silencing of HLA-G involved a DNA secondary structure generated in LINE1. The presence of a LINE1 gene silencer may explain the limited expression of HLA-G compared with other class I genes.
authors.affiliation: School of Medicine, Keio University, Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. mikeno@fujita-hu.ac.jp
authors.forename: Masashi
authors.initials: M
authors.lastname: Ikeno
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Suzuki
authors.forename: Megumi
authors.initials: M
authors.lastname: Kamiya
authors.forename: Yuji
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Jun
authors.initials: J
authors.lastname: Kudoh
authors.forename: Tsuneko
authors.initials: T
authors.lastname: Okazaki
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D022222:Chromosomes, Artificial, Human; D020868:Gene Silencing; D005822:Genetic Vectors; D016678:Genome; D059951:HLA-G Antigens / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D020084:Long Interspersed Nucleotide Elements; D051379:Mice; D009690:Nucleic Acid Conformation
chemical_list: D059951:HLA-G Antigens