Overexpression of OsFTL10 induces early flowering and improves drought tolerance in Oryza sativa L.

Abstract

Flowering time control is critically important for the reproductive accomplishment of higher plants as floral transition can be affected by both environmental and endogenous signals. Flowering Locus T-like (FTL) genes are major genetic determinants of flowering in plants. In rice, 13 OsFTL genes have been annotated in the genome and amongst them, Hd3a (OsFTL2) and RFT1 (OsFTL3) have been studied extensively and their functions are confirmed as central florigens that control rice flowering under short day and long day environment, respectively. In this report, a rice OsFTL gene, OsFTL10, was characterized, and its function on flowering and abiotic stress was investigated. The expression level of OsFTL10 was high in young seedlings and shown to be induced by GA3 and drought stress. Overexpression of OsFTL10 resulted in earlier flowering in rice plants by up to 2 weeks, through up-regulation of the downstream gene OsMADS15. OsFTL10 also regulated Ehd1 and OsMADS51 through a feedback mechanism. The OsFTL10 protein was also detected in both nucleus and cytoplasm. Furthermore, yeast two hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) results show that OsFTL10 could interact with multiple 14-3-3s, suggesting that OsFTL10 might function in a similar way to Hd3a in promoting rice flowering by forming a FAC complex with 14-3-3, and OsFD1. Further experiments revealed that constitutive expression of OsFTL10 improved the drought tolerance of transgenic plants by stimulating the expression of drought responsive genes. These results suggest that rice FTL genes might function in flowering promotion and responses to environmental signals.

Identification ofBrassica oleraceaorthologs of the PEBP family and their expression patterns in curd development and flowering in cauliflower

“…The FT gene encodes a long-distance mobile signaling protein called "florigen", which plays a central role in flowering regulation [3,7,8]. This gene belongs to the phosphatidylethanolamine-binding protein (PEBP) gene family, which exists in all kingdoms of life [9].…”

Exogenous ascorbic acid delayed leaf senescence of early flowering rice mutant FTL10

“…In agricultural production, premature senescence of leaves shortens the functional period of leaves and thus reduces the rice yield. The FTL10 is an early flowering line by overexpressing the OsFTL10 gene (Fang et al 2019). The expression level of OsFTL10 gene in FTL10 was significantly higher than that in the wild type.…”

“…Plant material: Oryza sativa L. cv. Zhonghua 11 (ZH-11), and an early flowering mutant FTL10 were used in this study (Fang et al 2019). The pasteurized seeds were planted in an artificial climate incubator and grown under controlled conditions with an average temperature of 33°C light/28°C dark, air humidity of 80%, and a photoperiod of 14 h light/10 h dark [PAR of 100 μmol(photon) m -2 s -1 ].…”

Drought Resistance by Engineering Plant Tissue-Specific Responses

“…Still, it has been proposed that DE can be used to obtain quick-growing, early-flowering cereal varieties, which would be especially useful in temperate regions like the Mediterranean area where terminal drought is expected to affect plants toward the end of the crop season (Shavrukov et al, 2017). Furthermore, it has been recently shown that OsFTL10, one of the 13 FLOWERING LOCUS T-LIKE (FTL) genes annotated in the rice genome, is induced by both drought stress and GA, and when overexpressed in transgenic rice plants confers early flowering and improves drought tolerance (Fang et al, 2019). However, as these transgenic rice lines were not tested in a field trial, it is unknown whether engineering FTL genes could deliver cereal varieties with superior drought performances and good yield in both dry and well-watered conditions.…”