CHARACTERIZATION OF LINNE, A NEW AUTOSOMAL ECLOSION RHYTHM MUTANT IN DROSOPHILA-SUBOBSCURA

A new putative gene, named linne, affecting circadian eclosion rhythm was found in a Norwegian strain of Drosophila subobscura. The phenotyp e of linne may be novel among Drosophila clock mutants. Eclosion is pr actically arrhythmic in light-dark cycles, but diel temperature cycles of 4-degrees-C amplitude effectively entrain eclosion in continuous l ight and in continuous darkness. After that, the rhythm continues in c onstant temperature and darkness, but unlike other strains, it continu es in constant temperature and light as well. Thus in the linne strain the coupling between light signals and pacemaker is disrupted, not th e pacemaker itself. Genetic effects of linne were tested in crosses wi th a wild strain. Arrhythmicity was recessive and autosomal and showed monogenic inheritance, suggesting that arrhythmicity in linne is base d on mutation on a single locus.