Abstract
Key message
Silencing SlAGL6 in tomato leads to fused sepal and green petal by influencing the expression of A-, B-class genes.
Abstract
AGAMOUS-LIKE6 (AGL6) lineage is an important clade MADS-box transcription factor and plays essential roles in various developmental programs especially in flower meristem and floral organ development. Here, we isolated a tomato AGL6 lineage gene SlAGL6 and successfully obtained several RNA interference (RNAi) lines. Silencing SlAGL6 led to abnormal fused sepals and light green petals with smaller size. The total chlorophyll content in transgenic petals increased and the morphology of epidermis cells altered. Further analysis showed that A-class gene MACROCALYX (MC) participating in sepal development and a NAC-domain gene GOBLET involving in boundary establishment were down-regulated in transgenic lines. In transgenic petals, two chlorophyll synthesis genes, Golden2-like1 (SlGLK1) and Golden2-like2 (SlGLK2), two photosystem-related genes, ribulose bisphosphate carboxylase small chain 3B (SlrbcS3B) and chlorophyll a/b-binding protein 7 (SlCab-7) were induced and three B-class genes TM6, TAP3 and SlGLO1 were repressed. These results suggest that SlAGL6 involves in tomato sepal and petal development.
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Acknowledgements
This work was supported by the Fundamental Research Funds for the Central Universities (No. 106112015CDJZR235504), Chongqing University Postgraduates’ Innovation Project (CYB15027) and Technology System of National Bulk Vegetable Industry–Eggplant Breeding Position (CARS-25-A-06).
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Communicated by Ray J. Rose.
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299_2017_2129_MOESM1_ESM.docx
Supplementary Table S1.Details of primers used in this study. Supplementary Table S2.The accession numbers of proteins contained in multiple sequence alignment and phylogenic analysis. Supplementary Table S3.Number of total sepal and normal dehiscent sepal. Observation and statistic of sepals were performed at 3 dpa when the flowers completely opened. (DOCX 22 KB)
299_2017_2129_MOESM2_ESM.tif
Supplementary Figure S1. Detection of SlAGL6 in flower and each floral organ of WT and transgenic lines. Floral organs were sampled at 2 dpa. Each value represents the mean± SE of three replicates. Asterisks indicate a significant difference (P<0.05) between WT and transgenic lines. (TIF 368 KB)
299_2017_2129_MOESM3_ESM.tif
Supplementary Figure S2. Expression analysis of SlNAM2 in sepals (a), MC (b) and TPI (c) in petals, TAG1, AGL11 in stamens and carpels, and two E-class genes in four floral organs (f, g). Expression profiles of SlNAM2 in sepals (a), MC (b) and TPI (c) in petals, TAG1 (d) and AGL11 (e) in stamens and carpels, TAGL2 (f) and TM5 (g) in four floral organs. Floral organs used in gene detection were sampled at 2 dpa. Each value represents the mean± SE of three replicates. Asterisks indicate a significant difference (P<0.05) between WT and transgenic lines. (TIF 407 KB)
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Yu, X., Chen, G., Guo, X. et al. Silencing SlAGL6, a tomato AGAMOUS-LIKE6 lineage gene, generates fused sepal and green petal. Plant Cell Rep 36, 959–969 (2017). https://doi.org/10.1007/s00299-017-2129-9
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DOI: https://doi.org/10.1007/s00299-017-2129-9