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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.

SUBMITTER: Ikeno M

PROVIDER: S-EPMC3510505 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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LINE1 family member is negative regulator of HLA-G expression.

Ikeno Masashi M Suzuki Nobutaka N Kamiya Megumi M Takahashi Yuji Y Kudoh Jun J Okazaki Tsuneko T

Nucleic acids research 20120921 21

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 investig ...[more]

PMID: 23002136

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