Linked Life Data

9783440

Source:http://linkedlifedata.com/resource/pubmed/id/9783440

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
1998-11-18
pubmed:abstractText
Two clock-controlled processes, overt circadian rhythmicity and the photoperiodic induction of diapause, are described in the blow fly, Calliphora vicina and the fruit fly, Drosophila melanogaster. Circadian locomotor rhythms of the adult flies reflect endogenous, self-sustained oscillations with a temperature compensated period. The free-running rhythms become synchronised (entrained) to daily light:dark cycles, but become arrhythmic in constant light above a certain intensity. Some flies show fragmented rhythms (internal desynchronisation) suggesting that overt rhythmicity is the product of a multioscillator (multicellular) system. Photoperiodic induction of larval diapause in C. vicina and of ovarian diapause in D. melanogaster is also based on the circadian system but seems to involve a separate mechanism at both the molecular and neuronal levels. For both processes in both species, the compound eyes and ocelli are neither essential nor necessary for photic entrainment, and the circadian clock mechanism is not within the optic lobes. The central brain is the most likely site for both rhythm generation and extra-optic photoreception. In D. melanogaster, a group of lateral brain neurons has been identified as important circadian pacemaker cells, which are possibly also photo-sensitive. Similar lateral brain neurons, staining for arrestin, a protein in the phototransduction 'cascade' and a selective marker for photoreceptors in both vertebrates and invertebrates, have been identified in C. vicina. Much less is known about the cellular substrate of the photoperiodic mechanism, but this may involve the pars intercerebralis region of the mid-brain.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
1354-2516
pubmed:author
pubmed:issnType
Print
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
155-64
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:articleTitle
Insect circadian rhythms and photoperiodism.
pubmed:affiliation
Institute of Cell, Animal and Population Biology, University of Edinburgh. davids@srv0.bio.ed.ac.uk
pubmed:publicationType
Journal Article, Review