Open AccessDynamic changes of genome sizes and gradual gain of cell‐specific distribution of C 4 enzymes during C 4 evolution in genus Flaveria
Author(s) -
Taniguchi Yukimi Y.,
Gowik Udo,
Kinoshita Yuto,
Kishizaki Risa,
Ono Naoaki,
Yokota Akiho,
Westhoff Peter,
Munekage Yuri N.
Publication year - 2021
Publication title -
the plant genome
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.403
H-Index - 41
ISSN - 1940-3372
DOI - 10.1002/tpg2.20095
Subject(s) - c4 photosynthesis , phosphoenolpyruvate carboxylase , biology , photorespiration , gene , genome , photosynthesis , gene expression , biochemistry , botany , genetics
C 4 plants are believed to have evolved from C 3 plants through various C 3 –C 4 intermediate stages in which a photorespiration‐dependent CO 2 concentration system known as C 2 photosynthesis operates. Genes involved in the C 4 cycle were thought to be recruited from orthologs present in C 3 species and developed cell‐specific expression during C 4 evolution. To understand the process of establishing C 4 photosynthesis, we performed whole‐genome sequencing and investigated expression and mesophyll‐ or bundle‐sheath‐cell‐specific localization of phosphoenolpyruvate carboxylase (PEPC), NADP‐malic enzyme (NADP‐ME), pyruvate, orthophosphate dikinase (PPDK) in C 3 , C 3 –C 4 intermediate, C 4 –like, and C 4 Flaveria species. While genome sizes vary greatly, the number of predicted protein‐coding genes was similar among C 3 , C 3 –C 4 intermediate, C 4 –like, and C 4 Flaveria species. Cell‐specific localization of the PEPC, NADP‐ME, and PPDK transcripts was insignificant or weak in C 3 –C 4 intermediate species, whereas these transcripts were expressed cell‐type specific in C 4 –like species. These results showed that elevation of gene expression and cell‐specific control of pre‐existing C 4 cycle genes in C 3 species was involved in C 4 evolution. Gene expression was gradually enhanced during C 4 evolution, whereas cell‐specific control was gained independently of quantitative transcriptional activation during evolution from C 3 –C 4 intermediate to C 4 photosynthesis in genus Flaveria .