A fly traveling at 4 A.M. from San Francisco to New York, however, was making very little
tim RNA before departure.
A fly moving at 8 P.M. from New York to San Francisco is producing maximum levels of
tim RNA, so protein lost by exposure to light in San Francisco is easily replaced after sunset in the new location.
We learned more about the mechanism behind the different molecular responses by examining the timing of the production of
tim RNA.