Final published version
Licence: CC BY: Creative Commons Attribution 4.0 International License
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Engineering chloroplast development in rice through cell-specific control of endogenous genetic circuits
AU - Lee, Dong-Yeon
AU - Hua, Lei
AU - Khoshravesh, Roxana
AU - Giuliani, Rita
AU - Kumar, Indrajit
AU - Cousins, Asaph
AU - Sage, Tammy L
AU - Hibberd, Julian M
AU - Brutnell, Thomas P
N1 - © 2021 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
PY - 2021/11/30
Y1 - 2021/11/30
N2 - The engineering of C4 photosynthetic activity into the C3 plant rice has the potential to nearly double rice yields. To engineer a two-cell photosynthetic system in rice, the rice bundle sheath (BS) must be rewired to enhance photosynthetic capacity. Here, we show that BS chloroplast biogenesis is enhanced when the transcriptional activator, Oryza sativa Cytokinin GATA transcription factor 1 (OsCGA1), is driven by a vascular specific promoter. Ectopic expression of OsCGA1 resulted in increased BS chloroplast planar area and increased expression of photosynthesis-associated nuclear genes (PhANG), required for the biogenesis of photosynthetically active chloroplasts in BS cells of rice. A further refinement using a DNAse dead Cas9 (dCas9) activation module driven by the same cell-type specific promoter, directed enhanced chloroplast development of the BS cells when gRNA sequences were delivered by the dCas9 module to the promoter of the endogenous OsCGA1 gene. Single gRNA expression was sufficient to mediate the transactivation of both the endogenous gene and a transgenic GUS reporter fused with OsCGA1 promoter. Our results illustrate the potential for tissue-specific dCas9-activation and the co-regulation of genes needed for multistep engineering of C4 rice.
AB - The engineering of C4 photosynthetic activity into the C3 plant rice has the potential to nearly double rice yields. To engineer a two-cell photosynthetic system in rice, the rice bundle sheath (BS) must be rewired to enhance photosynthetic capacity. Here, we show that BS chloroplast biogenesis is enhanced when the transcriptional activator, Oryza sativa Cytokinin GATA transcription factor 1 (OsCGA1), is driven by a vascular specific promoter. Ectopic expression of OsCGA1 resulted in increased BS chloroplast planar area and increased expression of photosynthesis-associated nuclear genes (PhANG), required for the biogenesis of photosynthetically active chloroplasts in BS cells of rice. A further refinement using a DNAse dead Cas9 (dCas9) activation module driven by the same cell-type specific promoter, directed enhanced chloroplast development of the BS cells when gRNA sequences were delivered by the dCas9 module to the promoter of the endogenous OsCGA1 gene. Single gRNA expression was sufficient to mediate the transactivation of both the endogenous gene and a transgenic GUS reporter fused with OsCGA1 promoter. Our results illustrate the potential for tissue-specific dCas9-activation and the co-regulation of genes needed for multistep engineering of C4 rice.
KW - C4 photosynthesis
KW - dCas9-mediated transcriptional activation
KW - rice bundle sheath
KW - chloroplast development
U2 - 10.1111/pbi.13660
DO - 10.1111/pbi.13660
M3 - Journal article
C2 - 34328250
VL - 19
SP - 2291
EP - 2303
JO - Plant Biotechnology Journal
JF - Plant Biotechnology Journal
SN - 1467-7644
IS - 11
ER -