Posted by Anna Nordén
Next time at the lab meeting (Tuesday, April 5th) we will discuss a review by Jennifer Marshall Graves about the evolution of vertebrate sex chromosomes with an emphasis on the variation and similarity of dosage compensation mechanisms in vertebrate clades. How it works, how it might have evolved, and general patterns.
Looking forward to a fruitful discussion. Time (10 am) and place (Argumetet) as usual.
Title: Evolution of vertebrate sex chromosomes and dosage compensation
Abstract: Differentiated sex chromosomes in mammals and other vertebrates evolved
independently but in strikingly similar ways. Vertebrates with
differentiated sex chromosomes share the problems of the unequal
expression of the genes borne on sex chromosomes, both between the sexes
and with respect to autosomes. Dosage compensation of genes on sex
chromosomes is surprisingly variable — and can even be absent — in
different vertebrate groups. Systems that compensate for different gene
dosages include a wide range of global, regional and gene-by-gene
processes that differ in their extent and their molecular mechanisms.
However, many elements of these control systems are similar across
distant phylogenetic divisions and show parallels to other gene
silencing systems. These dosage systems cannot be identical by descent
but were probably constructed from elements of ancient silencing
mechanisms that are ubiquitous among vertebrates and shared throughout