Send to

Choose Destination
Biochemistry. 1999 Jun 15;38(24):7689-95.

Circadian synthesis of a nuclear-encoded chloroplast glyceraldehyde-3-phosphate dehydrogenase in the dinoflagellate Gonyaulax polyedra is translationally controlled.

Author information

Department of Molecular & Cellular Biology, Harvard University, Cambridge, Massachusetts 02138-2020, USA.


The circadian clock has previously been shown to restrict synthesis of several proteins in the dinoflagellate Gonyaulax polyedra to only a few hours each day. We have identified one of these proteins as glyceraldehyde-3-phosphate dehydrogenase. Two nuclear genes encoding the enzyme have been cloned, one corresponding to a cytoplasmic isoform and the other to a plastid targeted protein. On the basis of protein microsequence data, we conclude that the synthesis of the plastid isoform is clock-regulated. This regulation is not related to mRNA levels, which remain constant throughout the cycle, suggesting a translational control mechanism, in contrast to the transcriptional regulation of GAPDH that has been demonstrated in Neurospora. Although the rhythm of synthesis has a high amplitude, the abundance and activity rhythms are greatly attenuated, which is attributed to the long half-life of the protein.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for American Chemical Society
Loading ...
Support Center