Journal article

The X factor: X chromosome dosage compensation in the evolutionarily divergent monotremes and marsupials

Deanne J Whitworth, Andrew J Pask

SEMINARS IN CELL & DEVELOPMENTAL BIOLOGY | ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD | Published : 2016

Abstract

Marsupials and monotremes represent evolutionarily divergent lineages from the majority of extant mammals which are eutherian, or placental, mammals. Monotremes possess multiple X and Y chromosomes that appear to have arisen independently of eutherian and marsupial sex chromosomes. Dosage compensation of X-linked genes occurs in monotremes on a gene-by-gene basis, rather than through chromosome-wide silencing, as is the case in eutherians and marsupials. Specifically, studies in the platypus have shown that for any given X-linked gene, a specific proportion of nuclei within a cell population will silence one locus, with the percentage of cells undergoing inactivation at that locus being high..

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University of Melbourne Researchers