StMADS11 Subfamily Gene PfMADS16 From Polypogon fugax Regulates Early Flowering and Seed Development

Abstract

The evolution of herbicide resistance in weedy plants leads to various adaptation traits including flowering time and seed germination. In our previous studies, we found an association of the early flowering phenotype with the ACCase inhibitor herbicide resistance genotype in a population of Polypogon fugax. MADS-box transcription factors are known to play pivotal roles in regulating plant flowering time. In this study, a SHORT VEGETATIVE PHASE (SVP)-like gene, belonging to the StMADS11 subfamily in the MADS-box family, was cloned from the early flowering P. fugax population (referred to as PfMADS16) and resistant to the herbicide clodinafop-propargyl. Overexpression of the SVP-like gene PfMADS16 in Arabidopsis thaliana resulted in early flowering and seed abortion. This is consistent with the phenotypic characters of resistant P. fugax plants, but contrary to the conventional role of SVP-like genes that usually suppress flowering. In addition, down regulation of the seed formation gene AtKTN1 in flowers of PfMADS16 transgenic Arabidopsis plants indicates that PfMADS16 may be indirectly associated with seed viability. Furthermore, one protein (PfMADS2) from the APETALA1 (AP1) subfamily interacting with PfMADS16 in P. fugax was identified with relevance to flowering time regulation. These results suggest that the PfMADS16 gene is an early flowering regulation gene associated with seed formation and viability in resistant P. fugax population. Our study provides potential application of PfMADS16 for integrated weed management (such as genetic-based weed control strategies) aiming to reduce the soil weed seedbank.

Overexpression of

“…Recently, we identified another gene PfMADS16 regulating early flowering and seed development in P. fugax (Zhou et al 2020). The role of PfAG5 identified in the current study is different to PfMADS16 as the former is not involved in seed development and interacts with different proteins.…”

“…Furthermore, we identified two PfAG5 interaction proteins in R P. fugax by the yeast two-hybrid and pull-down assays, and one (FRIGIDAlike) is reverent to flowering time regulation. This is among the very few studies on the regulation mechanism of early flowering in a weedy plant species (Zhou et al 2020). This knowledge will aid in future genetic approaches for better weed control strategies.…”

Isolation and Functional Characterization of Two SHORT VEGETATIVE PHASE Homologous Genes from Mango

“…MiSVP1 can significantly delay the flowering time of transgenic plants compared to that of WTplant, under MiSVP1 overexpression, the expression of endogenous genes AtFT and AtSOC1 in Arabidopsis decreased, while the expression of the endogenous gene AtFLC increased, which is consistent with the effects of PmSVP2 [ 23 ]. MiSVP2 significantly accelerated the flowering time of transgenic plants; additionally, the expression levels of endogenous genes exhibited opposite changes to those under MiSVP1 : the expression levels of the endogenous genes AtFT and AtSOC1 increased, while the expression of the endogenous gene AtFLC decreased, consistent with the effects of SVP -like gene PfMADS16 [ 42 ]. In conclusion, MiSVPs regulate flowering time in transgenic plants by regulating the expression levels of the FT and SOC1 genes.…”

“…For example, overexpression of Epimedium sagittatum EsSVP can produce early flowering lines and late flowering lines [ 41 ]. Overexpression of the Polypogon fugax SVP homologous gene PfMADS16 leads to early flowering in transgenic plants [ 42 ]. Overexpression of Phyllostachys violascens PvSVP1 and PvSVP2 can induce early flowering and floral organ variation [ 43 ].…”

“…In A. thaliana , SVP and FLC can interact with each other to form a heterodimer, SVP-FLC, which can be combined with the promoter regions of SOC1 and FT to regulate the expression of SOC1 and FT, thereby regulating the flowering in A. thaliana [ 12 , 25 ]. Research has found that SVP can interact with AP1 and participate in the regulation of the flowering stage [ 42 ]. In this study, overexpression of the MiSVP gene in A. thaliana caused no significant changes in the number of rosette leaves; however, it had a significant impact on flowering time.…”