The carbonate concentration mechanism of Pyropia yezoensis (Rhodophyta): evidence from transcriptomics and biochemical data
Open Access
- 15 September 2020
- journal article
- research article
- Published by Springer Science and Business Media LLC in BMC Plant Biology
- Vol. 20 (1), 1-12
- https://doi.org/10.1186/s12870-020-02629-4
Abstract
Pyropia yezoensis (Rhodophyta) is widely cultivated in East Asia and plays important economic, ecological and research roles. Although inorganic carbon utilization of P. yezoensis has been investigated from a physiological aspect, the carbon concentration mechanism (CCM) of P. yezoensis remains unclear. To explore the CCM of P. yezoensis, especially during its different life stages, we tracked changes in the transcriptome, photosynthetic efficiency and in key enzyme activities under different inorganic carbon concentrations. Photosynthetic efficiency demonstrated that sporophytes were more sensitive to low carbon (LC) than gametophytes, with increased photosynthesis rate during both life stages under high carbon (HC) compared to normal carbon (NC) conditions. The amount of starch and number of plastoglobuli in cells corresponded with the growth reaction to different inorganic carbon (Ci) concentrations. We constructed 18 cDNA libraries from 18 samples (three biological replicates per Ci treatment at two life cycles stages) and sequenced these using the Illumina platform. De novo assembly generated 182,564 unigenes, including approximately 275 unigenes related to CCM. Most genes encoding internal carbonic anhydrase (CA) and bicarbonate transporters involved in the biophysical CCM pathway were induced under LC in comparison with NC, with transcript abundance of some PyCAs in gametophytes typically higher than that in sporophytes. We identified all key genes participating in the C4 pathway and showed that their RNA abundances changed with varying Ci conditions. High decarboxylating activity of PEPCKase and low PEPCase activity were observed in P. yezoensis. Activities of other key enzymes involved in the C4-like pathway were higher under HC than under the other two conditions. Pyruvate carboxylase (PYC) showed higher carboxylation activity than PEPC under these Ci conditions. Isocitrate lyase (ICL) showed high activity, but the activity of malate synthase (MS) was very low. We elucidated the CCM of P. yezoensis from transcriptome and enzyme activity levels. All results indicated at least two types of CCM in P. yezoensis, one involving CA and an anion exchanger (transporter), and a second, C4-like pathway belonging to the PEPCK subtype. PYC may play the main carboxylation role in this C4-like pathway, which functions in both the sporophyte and gametophyte life cycles.Keywords
This publication has 43 references indexed in Scilit:
- The First Symbiont-Free Genome Sequence of Marine Red Alga, Susabi-nori (Pyropia yezoensis)PLOS ONE, 2013
- Characterization of the global transcriptome for Pyropia haitanensis(Bangiales, Rhodophyta) and development of cSSR markersBMC Genomics, 2013
- Profiling of the transcriptome of Porphyra yezoensis with Solexa sequencing technologyChinese Science Bulletin, 2011
- Characterization of a Bifunctional Glyoxylate Cycle Enzyme, Malate Synthase/Isocitrate Lyase, of Euglena gracilisThe Journal of Eukaryotic Microbiology, 2011
- Diversity of carbon use strategies in a kelp forest community: implications for a high CO2 oceanGlobal Change Biology, 2011
- Internal Architecture of Mitochondrial Complex I from Arabidopsis thalianaTHE PLANT CELL ONLINE, 2010
- Mitochondrial-Driven Bicarbonate Transport Supports Photosynthesis in a Marine MicroalgaPlant Physiology, 2002
- The ultrastructure of separated and cultured cell ofPorphyra yezoensisChinese Journal of Oceanology and Limnology, 2001
- Porphyra monospore system (Bangiales, Rhodophyta): A model for the developmental biology of marine plantsPhycological Research, 1998
- The effect of pH upon the photosynthesis of littoral marine algaeProtoplasma, 1963