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Evolution of photosensory pineal organs in new light: the fate of neurodocrine photoreceptors

Ekström, Peter LU and Meissl, Hilmar (2003) In Royal Society of London. Philosophical Transactions B. Biological Sciences 358(1438). p.1679-1700
Abstract
Pineal evolution is envisaged as a gradual transformation of pinealocytes (a gradual regression of pinealocyte sensory capacity within a particular cell line), the so-called sensory cell line of the pineal organ. In most non-mammals the pineal organ is a directly photosensory organ, while the pineal organ of mammals (epiphysis cerebri) is a non-sensory neuroendocrine organ under photoperiod control. The phylogenetic transformation of the pineal organ is reflected in the morphology and physiology of the main parenchymal cell type, the pinealocyte. In anamniotes, pinealocytes with retinal cone photoreceptor-like characteristics predominate, whereas in sauropsids so-called rudimentary photoreceptors predominate. These have well-developed... (More)
Pineal evolution is envisaged as a gradual transformation of pinealocytes (a gradual regression of pinealocyte sensory capacity within a particular cell line), the so-called sensory cell line of the pineal organ. In most non-mammals the pineal organ is a directly photosensory organ, while the pineal organ of mammals (epiphysis cerebri) is a non-sensory neuroendocrine organ under photoperiod control. The phylogenetic transformation of the pineal organ is reflected in the morphology and physiology of the main parenchymal cell type, the pinealocyte. In anamniotes, pinealocytes with retinal cone photoreceptor-like characteristics predominate, whereas in sauropsids so-called rudimentary photoreceptors predominate. These have well-developed secretory characteristics, and have been interpreted as intermediaries between the anamniote pineal photoreceptors and the mammalian non-sensory pinealocytes. We have re-examined the original studies on which the gradual transformation hypothesis of pineal evolution is based, and found that the evidence for this model of pineal evolution is ambiguous. In the light of recent advances in the understanding of neural development mechanisms, we propose a new hypothesis of pineal evolution, in which the old notion 'gradual regression within the sensory cell line' should be replaced with 'changes in fate restriction within the neural lineage of the pineal field'. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
vertebrate photoreceptors, electron, microscopy, melatonin, opsin, pineal gland
in
Royal Society of London. Philosophical Transactions B. Biological Sciences
volume
358
issue
1438
pages
1679 - 1700
publisher
Royal Society
external identifiers
  • pmid:14561326
  • wos:000186255500005
  • scopus:0142216226
ISSN
1471-2970
DOI
language
English
LU publication?
yes
id
fcb0dbc3-f954-4301-be34-317c4a57267a (old id 297007)
date added to LUP
2007-08-29 14:44:13
date last changed
2018-05-29 10:32:46
@article{fcb0dbc3-f954-4301-be34-317c4a57267a,
  abstract     = {Pineal evolution is envisaged as a gradual transformation of pinealocytes (a gradual regression of pinealocyte sensory capacity within a particular cell line), the so-called sensory cell line of the pineal organ. In most non-mammals the pineal organ is a directly photosensory organ, while the pineal organ of mammals (epiphysis cerebri) is a non-sensory neuroendocrine organ under photoperiod control. The phylogenetic transformation of the pineal organ is reflected in the morphology and physiology of the main parenchymal cell type, the pinealocyte. In anamniotes, pinealocytes with retinal cone photoreceptor-like characteristics predominate, whereas in sauropsids so-called rudimentary photoreceptors predominate. These have well-developed secretory characteristics, and have been interpreted as intermediaries between the anamniote pineal photoreceptors and the mammalian non-sensory pinealocytes. We have re-examined the original studies on which the gradual transformation hypothesis of pineal evolution is based, and found that the evidence for this model of pineal evolution is ambiguous. In the light of recent advances in the understanding of neural development mechanisms, we propose a new hypothesis of pineal evolution, in which the old notion 'gradual regression within the sensory cell line' should be replaced with 'changes in fate restriction within the neural lineage of the pineal field'.},
  author       = {Ekström, Peter and Meissl, Hilmar},
  issn         = {1471-2970},
  keyword      = {vertebrate photoreceptors,electron,microscopy,melatonin,opsin,pineal gland},
  language     = {eng},
  number       = {1438},
  pages        = {1679--1700},
  publisher    = {Royal Society},
  series       = {Royal Society of London. Philosophical Transactions B. Biological Sciences},
  title        = {Evolution of photosensory pineal organs in new light: the fate of neurodocrine photoreceptors},
  url          = {http://dx.doi.org/},
  volume       = {358},
  year         = {2003},
}