C4 and crassulacean acid metabolism within a single leaf: deciphering key components behind a rare photosynthetic adaptation.

Collapse authors list.
Ferrari, Renata C, Bittencourt, Priscila P, Rodrigues, Maria A, Moreno-Villena, Jose J, Alves, Frederico RR, Gastaldi, Vinícius D, Boxall, Susanna F, Dever, Louisa V ORCID: 0000-0001-7801-5622, Demarco, Diego, Andrade, Sónia CS et al (show 3 more authors) , Edwards, Erika J, Hartwell, James ORCID: 0000-0001-5000-223X and Freschi, Luciano (2020) C4 and crassulacean acid metabolism within a single leaf: deciphering key components behind a rare photosynthetic adaptation. The New Phytologist, 225 (4). pp. 1699-1714.

	Text main_text_revised.docx - Author Accepted Manuscript Download (150kB)
	Image Fig1_revised.tif - Author Accepted Manuscript Download (8MB) | Preview
	Image Fig2.tif - Author Accepted Manuscript Download (1MB) | Preview
	Image Fig3.tif - Author Accepted Manuscript Download (1MB) | Preview
	Image Fig4.tif - Author Accepted Manuscript Download (6MB) | Preview
	Image Fig5.tif - Author Accepted Manuscript Download (481kB) | Preview
	Image Fig6_revised.tif - Author Accepted Manuscript Download (65MB) | Preview
	Image Fig7_revised.tif - Author Accepted Manuscript Download (10MB) | Preview
	Spreadsheet Tables_S1-S8_revised.xlsx - Author Accepted Manuscript Download (11MB)
	Text Fig_S7_revised.pdf - Author Accepted Manuscript Download (925kB) | Preview
	Text Fig_S8_revised.pdf - Author Accepted Manuscript Download (782kB) | Preview
	Text Fig_S9_revised.pdf - Author Accepted Manuscript Download (679kB) | Preview
	Text New_Phytologist_SI_revised_1.pdf - Author Accepted Manuscript Download (1MB) | Preview

Abstract

Though biochemically related, C4 and crassulacean acid metabolism (CAM) systems are expected to be incompatible. However, Portulaca species, including P. oleracea, operate C4 and CAM within a single leaf, and the mechanisms behind this unique photosynthetic arrangement remain largely unknown. Here, we employed RNA-seq to identify candidate genes involved exclusively or shared by C4 or CAM, and provided an in-depth characterization of their transcript abundance patterns during the drought-induced photosynthetic transitions in P. oleracea. Data revealed fewer candidate CAM-specific genes than those recruited to function in C4 . The putative CAM-specific genes were predominantly involved in nighttime primary carboxylation reactions and malate movement across the tonoplast. Analysis of gene transcript-level regulation and photosynthetic physiology indicated that C4 and CAM co-exist within a single P. oleracea leaf under mild drought conditions. Developmental and environmental cues were shown to regulate CAM expression in stems, whereas the shift from C4 to C4 -CAM hybrid photosynthesis in leaves was strictly under environmental control. Moreover, efficient starch turnover was identified as part of the metabolic adjustments required for CAM operation in both organs. These findings provide insights into C4 /CAM connectivity and compatibility, contributing to a deeper understanding of alternative ways to engineer CAM into C4 crop species.

Item Type:	Article
Uncontrolled Keywords:	C4, crassulacean acid metabolism, drought stress, facultative CAM, Portulaca oleracea, RNA-seq, transcriptome
Depositing User:	Symplectic Admin
Date Deposited:	28 Oct 2019 09:26
Last Modified:	19 Jan 2023 00:21
DOI:	10.1111/nph.16265
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3059531