Please see answers to specific points below. Currently just one nucleus is shown for the whole paper. This article has the two sex chromosomes are considered autosomes def in Memphis cited by other articles in PMC. B Comparison of transgene expression at different sites along a chromosome reveals only minimal position effects.
Using single-copy transgenes integrated throughout the Caenorhabditis elegans genome, we show that expression of all X-linked transgenes is balanced between XX hermaphrodites and XO males.
Here in a different exploration of Ohno's hypothesis, we asked whether a chromosome-wide mechanism operates in C. The distance doesn't appear to be limited for dosage compensation. Middle Under a model of no X-chromosome-wide upregulation, dosage compensated transgenes would be expressed at half the level of transgenes on autosomes due to repression by the DCC.
Hence, DCC binding near a gene could not be the sole determinant of dosage compensation.
Author contributions BSW, Conception and design, Acquisition of data, Analysis and interpretation of data, Drafting or revising the article. In a second step, overexpression of genes on female X chromosomes would be offset by inactivating one of the two X chromosomes.
Interestingly, the authors of the present paper show that a previous evolutionary comparison that had concluded that there was no evolutionary upregulation in C.