FN Archimer Export Format
PT J
TI Decoupling light harvesting, electron transport and carbon fixation during prolonged darkness supports rapid recovery upon re-illumination in the Arctic diatom Chaetoceros neogracilis
BT 
AF Lacour, Thomas
   Morin, Philippe-Israël
   Sciandra, Théo
   Donaher, Natalie
   Campbell, Douglas A.
   Ferland, Joannie
   Babin, Marcel
AS 1:1,2,3;2:1,2;3:1,2;4:4;5:4;6:1,2;7:1,2;
FF 1:;2:;3:;4:;5:;6:;7:;
C1 Takuvik Joint International Laboratory, CNRS (France) & ULaval (Canada), Département de BiologieUniversité LavalQuébec, Canada
   Takuvik Joint International Laboratory, CNRS (France) & ULaval (Canada), Département de BiologieUniversité LavalQuébec, Canada
   IFREMER, Physiol & Biotechnol Algae LabsNantes Cedex 03, France
   Department of BiologyMount Allison UniversitySackville, Canada
C2 CNRS, FRANCE
   UNIV LAVAL, CANADA
   IFREMER, Physiol & Biotechnol Algae LabsNantes Cedex 03, France
   UNIV SACKVILLE, CANADA
IF 1.728
TC 24
UR https://archimer.ifremer.fr/doc/00499/61066/64597.pdf
LA English
DT Article
DE ;Arctic microalgae;Polar night;Diatom;Darkness;Photosynthesis;Growth rate;Temperature
AB During winter in the Arctic marine ecosystem, diatoms have to survive long periods of darkness caused by low sun elevations and the presence of sea ice covered by snow. To better understand how diatoms survive in the dark, we subjected cultures of the Arctic diatom Chaetoceros neogracilis to a prolonged period of darkness (1 month) and to light resupply. Chaetoceros neogracilis was not able to grow in the dark but cell biovolume remained constant after 1 month in darkness. Rapid resumption of photosynthesis and growth recovery was also found when the cells were transferred back to light at four different light levels ranging from 5 to 154 µmol photon m−2 s−1. This demonstrates the remarkable ability of this species to re-initiate growth over a wide range of irradiances even after a prolonged period in the dark with no apparent lag period or impact on survival. Such recovery was possible because C. neogracilis cells preserved their Chl a content and their light absorption capabilities. Carbon fixation capacity was down-regulated (ninefold dark decrease in PCm) much more than was the photochemistry in PSII (2.3-fold dark decrease in ETRm). Rubisco content, which remained unchanged after one month in the dark, was not responsible for the decrease in PCm. The decrease in PSII activity was partially related to the induction of sustained non-photochemical quenching (NPQ) as we observed an increase in diatoxanthin content after one month in the dark. 
PY 2019
SO Polar Biology
SN 0722-4060
PU Springer Science and Business Media LLC
VL 42
IS 10
UT 000495702400001
BP 1787
EP 1799
DI 10.1007/s00300-019-02507-2
ID 61066
ER

EF