The FLOWERING LOCUS T LIKE 2-1 gene of Chenopodium triggers precocious flowering in Arabidopsis seedlings

ABSTRACT

The FLOWERING LOCUS T (FT) gene is the essential integrator of flowering regulatory pathways in angiosperms. The paralogs of the FT gene may perform antagonistic functions, as exemplified by BvFT1, that suppresses flowering in Beta vulgaris, unlike the paralogous activator BvFT2. The roles of FT genes in other amaranths were less investigated. Here, we transformed Arabidopsis thaliana with the FLOWERING LOCUS T like (FTL) genes of Chenopodium ficifolium and found that both CfFTL1 and CfFTL2–1 accelerated flowering, despite having been the homologs of the Beta vulgaris floral promoter and suppressor, respectively. The floral promotive effect of CfFTL2–1 was so strong that it caused lethality when overexpressed under the 35S promoter. CfFTL2–1 placed in an inducible cassette accelerated flowering after induction with methoxyphenozide. The spontaneous induction of CfFTL2–1 led to precocious flowering in some primary transformants even without chemical induction. The CqFT2–1 homolog from Chenopodium quinoa had the same impact on viability and flowering as CfFTL2–1 when transferred to A. thaliana. After the FTL gene duplication in Amaranthaceae, the FTL1 copy maintained the role of floral activator. The second copy FTL2 underwent subsequent duplication and functional diversification, which enabled it to control the onset of flowering in amaranths to adapt to variable environments.

SUMMARY

The FLOWERINGLOCUS T like 2–1 gene of Chenopodium ficifolium andChenopodium quinoa acts as a strong activator of flowering in Arabidopsis, triggering flowering at cotyledon stage and causing lethality when overexpressed.

KEYWORDS:

• Chenopodium
• flowering
• FLOWERING LOCUS T like genes
• floral induction
• lethality

Acknowledgments

The authors are grateful to Lukáš Synek for the photo of flowering Arabidopsis seedlings. They acknowledge the valuable comments and linguistic help by Eric N. Jellen. This work was supported by the Czech Science Foundation (GAČR) grant 19-01639S to H.S.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contribution statement

HS: conceptualization; OAJA, CB, TM, D G-L, KE, ZV and HS: methodology; OAJA, MK and DG-L: resources; HS: writing – original draft; OAJA, DG-L, TM, MK and HS: writing – review & editing; HS: supervision; HS: funding acquisition.

Abbreviations

CaMV, Cauliflower Mosaic Virus; FT, FLOWERING LOCUS T; FTL, FLOWERING LOCUS T like; MAR, Matrix attachment region; UBQ, UBIQUITINE;

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15592324.2023.2239420

Additional information

Funding

The work was supported by the Grantová Agentura České Republiky [19-01639S].