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Winter disruption of the circadian clock in chestnut.

ABSTRACT: Circadian clock performance during winter dormancy has been investigated in chestnut by using as marker genes CsTOC1 and CsLHY, which are homologous to essential components of the central circadian oscillator in Arabidopsis. During vegetative growth, mRNA levels of these two genes in chestnut seedlings and adult plants cycled daily, as expected. However, during winter dormancy, CsTOC1 and CsLHY mRNA levels were high and did not oscillate, indicating that the circadian clock was altered. A similar disruption was induced by chilling chestnut seedlings (to 4 degrees C). Normal cycling resumed when endodormant or cold-treated plants were returned to 22 degrees C. The behavior of CsTOC1 and CsLHY during a cold response reveals a relevant aspect of clock regulation not yet encountered in Arabidopsis.

SUBMITTER: Ramos A

PROVIDER: S-EPMC1100755 | biostudies-literature | 2005 May

REPOSITORIES: biostudies-literature

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Winter disruption of the circadian clock in chestnut.

Ramos Alberto A Pérez-Solís Estefanía E Ibáñez Cristian C Casado Rosa R Collada Carmen C Gómez Luis L Aragoncillo Cipriano C Allona Isabel I

Proceedings of the National Academy of Sciences of the United States of America 20050428 19

Circadian clock performance during winter dormancy has been investigated in chestnut by using as marker genes CsTOC1 and CsLHY, which are homologous to essential components of the central circadian oscillator in Arabidopsis. During vegetative growth, mRNA levels of these two genes in chestnut seedlings and adult plants cycled daily, as expected. However, during winter dormancy, CsTOC1 and CsLHY mRNA levels were high and did not oscillate, indicating that the circadian clock was altered. A simila ...[more]

PMID: 15860586

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