INSTEAD of being packed together on chromosomes with hundreds and thousands
of neighbours, some of the genes in dinoflagellates鈥攖he floating algae
that sometimes produce toxic 鈥渞ed tides鈥濃�攅ach have a chromosome all to
themselves.
Chloroplasts, the chlorophyll-carrying packets in plants, have their own DNA
and probably evolved from bacteria that formed a partnership with a primordial
plant cell. Not all chloroplasts are alike, however. Zhaoduo Zhang and
colleagues at the University of British Columbia report this week in
Nature (vol 400, p 155) that the nine chloroplast genes in dinoflagellates
each occupy their own loop of DNA.
The researchers say that this strange arrangement may explain why these genes
have been so hard to sequence until now.
Advertisement