Science, Vol 263, Issue 5153, 1606-1609
Copyright © 1994 by American Association for the Advancement of Science
Block in nuclear localization of period protein by a second clock mutation, timeless
LB Vosshall,
JL Price,
A Sehgal,
L Saez,
and
MW Young
Howard Hughes Medical Institute, National Science Foundation Science and Technology Center for Biological Timing, and Laboratory of Genetics, Rockefeller University, New York, NY 10021.
In wild-type Drosophila, the period protein (PER) is found in nuclei of the eyes and brain, and PER immunoreactivity oscillates with a circadian rhythm. The studies described here indicate that the nuclear localization of PER is blocked by timeless (tim), a second chromosome mutation that, like per null mutations, abolishes circadian rhythms. PER fusion proteins without a conserved domain (PAS) and some flanking sequences are nuclear in tim mutants. This suggests that a segment of PER inhibits nuclear localization in tim mutants. The tim gene may have a role in establishing rhythms of PER abundance and nuclear localization in wild-type flies.
