English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Background  Genomic imprinting causes parent-of-origin specific gene expression by differential epigenetic modifications between two parental genomes. We previously reported that there is no evidence of genomic imprinting of  CDKN1C  in the  KCNQ1  domain in the placenta of an Australian marsupial, the tammar wallaby ( Macropus eugenii ) whereas tammar  IGF2  and  H19 , located adjacent to the  KCNQ1  domain in eutherian mammals, are imprinted. We have now identified and characterised the marsupial orthologue of  PHLDA2 , another gene in the  KCNQ1  domain (also known as  IPL  or  TSSC3 ) that is imprinted in eutherians. In mice,  Phlda2  is a dose-sensitive negative regulator of placental growth, as  Cdkn1c  is for embryonic growth.    Results  Tammar  PHLDA2  is highly expressed in the yolk sac placenta compared to other fetal tissues, confirming a similar expression pattern to that of mouse  Phlda2 . However, tammar  PHLDA2  is biallelically expressed in both the fetus and yolk sac placenta, so it is not imprinted. The lack of imprinting in tammar  PHLDA2  suggests that the acquisition of genomic imprinting of the  KCNQ1  domain in eutherian mammals, accompanied with gene dosage reduction, occurred after the split of the therian mammals into the marsupials and eutherians.    Conclusions  Our results confirm the idea that acquisition of genomic imprinting in the  KCNQ1  domain occurred specifically in the eutherian lineage after the divergence of marsupials, even though imprinting of the adjacent  IGF2-H19  domain arose before the marsupial-eutherian split. These data are consistent with the hypothesis that genomic imprinting of the  KCNQ1  domain may have contributed to the evolution of more complex placentation in the eutherian lineage by reduction of the gene dosage of negative regulators for both embryonic and placental growth.

Characterisation of marsupial PHLDA2 reveals eutherian specific acquisition of imprinting