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The circadian clock plays a vital role in monarch butterfly (Danaus plexippus) migration by providing the timing component of time-compensated sun compass orientation, a process that is important for successful navigation. We therefore evaluated the monarch clockwork by focusing on the functions of a Drosophila-like cryptochrome (cry), designated cry1, and(More)
We examined Period (PER) protein regulation in the brain of the silkmoth Antheraea pernyi. PER expression is restricted to the cytoplasm and axons of eight neurons, with no evidence of temporal movement into the nucleus. These neurons appear to be circadian clock cells, because PER and per mRNA are colocalized and their levels oscillate in these cells,(More)
Migratory monarch butterflies (Danaus plexippus) use a time-compensated sun compass to navigate to their overwintering grounds in Mexico. Although polarized light is one of the celestial cues used for orientation, the spectral content (color) of that light has not been fully explored. We cloned the cDNAs of three visual pigment-encoding opsins (ultraviolet(More)
The period (per) gene of Drosophila plays an important role in circadian clock function. Interestingly, homologs of per have not been cloned outside of dipteran species. Using a PCR strategy, we now report the cloning of the cDNA of a per homolog from the silkmoth Antheraea pernyi. The cDNA encodes a protein of 849 amino acids, which shows highest identity(More)
Using a PCR strategy, we have cloned the cDNA for prothoracicotropic hormone (PTTH) from the giant silkmoth, Antheraea pernyi. The A. pernyi PTTH cDNA encodes a preprohormone of 221 amino acids that is 51 and 71% identical at the amino acid level with Bombyx mori and Samia cynthia ricini PTTHs, respectively. Bacterially expressed, recombinant A. pernyi PTTH(More)
Photoperiodic signal stimulates induction of larval diapause in Chymomyza costata. Larvae of NPD strain (npd-mutants) do not respond to photoperiod. Our previous results indicated that the locus npd could code for the timeless gene and its product might represent a molecular link between circadian and photoperiodic clock systems. Here we present results of(More)
Rhythmicity of the rat suprachiasmatic nucleus (SCN), a site of the circadian pacemaker, is affected by daylength; that is, by the photoperiod. Whereas various markers of rhythmicity have been followed, so far there have been no studies on the effect of the photoperiod on the expression of the clock genes in the rat SCN. To fill the gap and to better(More)
Investigations performed on adult insects revealed that putative components of the central pacemaker, the protein Period (PER) and the pigment-dispersing hormone (PDH), are immunocytochemically detectable in discrete sets of brain neurons throughout the class of Insecta, represented by a bristletail, mayfly, damselfly, 2 locust species, stonefly, 2 bug(More)
The circadian mechanism appears remarkably conserved between Drosophila and mammals, with basic underlying negative and positive feedback loops, cycling gene products, and temporally regulated nuclear transport involving a few key proteins. One of these negative regulators is PERIOD, which in Drosophila shows very similar temporal and spatial regulation to(More)
Homologs of the Drosophila clock gene per have recently been cloned in Lepidopteran and Blattarian insect species. To assess the extent to which clock mechanisms are conserved among phylogenetically distant species, we determined whether PER protein from the silkmoth Antheraea pernyi can function in the Drosophila circadian timing system. When expressed in(More)