Delayed leaf greening involves a major shift in the expression of cytosolic and mitochondrial ribosomes to plastid ribosomes in the highly phosphorus-use-efficient Hakea prostrata (Proteaceae)

Authors

Toby Bird, The University of Western Australia
Benjamin J. Nestor, The University of Western Australia
Philipp E. Bayer, The University of Western Australia
Guannan Wang, Louisiana State University
Albina Ilyasova, The University of Western Australia
Clément E. Gille, The University of Western Australia
Bryce E.H. Soraru, The University of Western Australia
Kosala Ranathunge, The University of Western Australia
Anita A. Severn-Ellis, The University of Western Australia
Ricarda Jost, The University of Western Australia
Wolf Rüdiger Scheible, Noble Research Institute
Maheshi Dassanayake, Louisiana State University
Jacqueline Batley, The University of Western Australia
David Edwards, The University of Western Australia
Hans Lambers, The University of Western Australia
Patrick M. Finnegan, The University of Western Australia

Document Type

Article

Publication Date

3-1-2024

Abstract

Background and aims: Hakea prostrata (Proteaceae) is a highly phosphorus-use-efficient plant native to southwest Australia. It maintains a high photosynthetic rate at low leaf phosphorus (P) and exhibits delayed leaf greening, a convergent adaptation that increases nutrient-use efficiency. This study aimed to provide broad physiological and gene expression profiles across leaf development, uncovering pathways leading from young leaves as nutrient sinks to mature leaves as low-nutrient, energy-transducing sources. Methods: To explore gene expression underlying delayed greening, we analysed a de novo transcriptome for H. prostrata across five stages of leaf development. Photosynthesis and respiration rates, and foliar pigment, P and nitrogen (N) concentrations were determined, including the division of P into five biochemical fractions. Key results: Transcripts encoding functions associated with leaf structure generally decreased in abundance across leaf development, concomitant with decreases in foliar concentrations of 85% for anthocyanins, 90% for P and 70% for N. The expression of genes associated with photosynthetic function increased during or after leaf expansion, in parallel with increases in photosynthetic pigments and activity, much later in leaf development than in species that do not have delayed greening. As leaves developed, transcript abundance for cytosolic and mitochondrial ribosomal proteins generally declined, whilst transcripts for chloroplast ribosomal proteins increased. Conclusions: There was a much longer temporal separation of leaf cell growth from chloroplast development in H. prostrata than is found in species that lack delayed greening. Transcriptome-guided analysis of leaf development in H. prostrata provided insight into delayed greening as a nutrient-saving strategy in severely phosphorus-impoverished landscapes.

Publication Source (Journal or Book title)

Plant and Soil

First Page

7

Last Page

30

Recommended Citation

Bird, T., Nestor, B., Bayer, P., Wang, G., Ilyasova, A., Gille, C., Soraru, B., Ranathunge, K., Severn-Ellis, A., Jost, R., Scheible, W., Dassanayake, M., Batley, J., Edwards, D., Lambers, H., & Finnegan, P. (2024). Delayed leaf greening involves a major shift in the expression of cytosolic and mitochondrial ribosomes to plastid ribosomes in the highly phosphorus-use-efficient Hakea prostrata (Proteaceae). Plant and Soil, 496 (1-2), 7-30. https://doi.org/10.1007/s11104-023-06275-1