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bioRxiv · 10.1101/2020.01.20.913376

Smchd1 is a maternal effect gene required for autosomal imprinting

Wanigasuriya, I.·Gouil, Q.·Kinkel, S. A.·Tapia del Fierro, A.·Beck, T.·Roper, E. E. A.·Breslin, K.·Stringer, J.·Hutt, K.·Lee, H. J.·Keniry, A.·Ritchie, M. E.·Blewitt, M. E.
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Abstract

Genomic imprinting establishes parental allele-biased expression of a suite of mammalian genes based on parent-of-origin specific epigenetic marks. These marks are under the control of maternal effect proteins supplied in the oocyte. Here we report the epigenetic repressor Smchd1 as a novel maternal effect gene that regulates imprinted expression of 16 genes. Most Smchd1-sensitive genes only show loss of imprinting post-implantation, indicating maternal Smchd1s long-lived epigenetic effect. Sm-chd1-sensitive genes include both those controlled by germline polycomb marks and germline DNA methylation imprints; however, Smchd1 differs to other maternal effect genes that regulate the latter group, as Smchd1 does not affect germline DNA methylation imprints. Instead, Smchd1-sensitive genes are united by their reliance on polycomb-mediated histone methylation marks as germline or secondary imprints. We propose that Smchd1 translates these imprints to establish a heritable chromatin state required for imprinted expression later in development, revealing a new mechanism for maternal effect genes.

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Wanigasuriya, I., Gouil, Q., Kinkel, S. A., Tapia del Fierro, A., Beck, T., Roper, E. E. A., Breslin, K., Stringer, J., Hutt, K., Lee, H. J., Keniry, A., Ritchie, M. E., Blewitt, M. E.. 2020-01-21. Smchd1 is a maternal effect gene required for autosomal imprinting. https://doi.org/10.1101/2020.01.20.913376

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