The tomato CONSTANS-LIKE protein SlCOL1 regulates fruit yield by repressing SFT gene expression

Abstract

Background CONSTANS (CO) and CONSTANS-LIKE (COL) transcription factors have been known to regulate a series of cellular processes including the transition from the vegetative growth to flower development in plants. However, their role in regulating fruit yield in tomato is poorly understood. Result In this study, the tomato ortholog of Arabidopsis CONSTANS, SlCOL1, was shown to play key roles in the control of flower development and fruit yield. Suppression of SlCOL1 expression in tomato was found to lead to promotion of flower and fruit development, resulting in increased tomato fruit yield. On the contrary, overexpression of SlCOL1 disturbed flower and fruit development, and significantly reduced tomato fruit yield. Genetic and biochemical evidence indicated that SlCOL1 controls inflorescence development by directly binding to the promoter region of tomato inflorescence-associated gene SINGLE-FLOWER TRUSS (SFT) and negatively regulating its expression. Additionally, we found that SlCOL1 can also negatively regulate fruit size in tomato. Conclusions Tomato SlCOL1 binds to the promoter of the SFT gene, down-regulates its expression, and plays a key role in reducing the fruit size.

Overexpression of tomatoSlBBX16andSlBBX17impacts fruit development and gibberellin metabolism

“…In this regard, the biological functions of CO-like (COL) genes in tomato remain elusive. Recently, Sl COL1 (Solyc02g089540) was shown to interact with the SFT promoter repressing its transcription and consequently inhibiting the flowering transition (Cui et al, 2022). Considering that miP1a/b interacts with At CO regulating its activity, we tested by Y2H the interaction between Sl BBX16 and Sl BBX17 and Sl COL1.…”

“…The evidence that both TCMP-2 and Sl BBX16/17 showed no direct interaction by Y2H with At CO and Sl COL1 (this work and Molesini et al, 2020) highlights the differences in the flowering control system between Arabidopsis and tomato. In this regard, Sl COL1 has been shown to bind the SFT promoter and negatively regulate its expression (Cui et al, 2022). Based on our results, TCMP-2 and Sl BBX17 activity in the tomato flowering process appeared independent of the Sl COL1/SFT regulatory module.…”

“…In tomato, which is a day-neutral species, the flowering transition is principally regulated by the balance between the activity of the florigen Single Flower Truss ( SFT ), which is the ortholog of FT , and that of antiflorigens, such as Self Pruning ( SP ) and SP5G , which maintain vegetative growth. Recently, it has been shown that Sl COL1, the ortholog of At CO, is able to bind the promoter region of SFT to repress its expression (Cui et al, 2022). Accordingly, RNA silencing of SlCOL1 led to the promotion of flowering and increased fruit yield.…”

GmCOL4-GmZTL1 interaction co-regulates GmSBH1 to improve seed deterioration under high temperature and humidity stress and affect leaf growth and development

“…While CO and its related proteins were likely to be regulators not only of owering pathways, but might have additional roles in the regulation of genes involved in other important plant processes (Tiwari et al, 2010). Tomato SlCOL1 bound to the promoter of the SFT gene, down-regulated its expression, and played a key role in reducing the fruit size (Cui et al, 2022). GmCOL1a bound directly to the Myc(bHLH)-binding and Che-binding motifs of GmLEA and GmP5CS promoters to stimulate mRNA expression and enhance the tolerance to salt and drought stresses in soybean (Xu et al, 2023).…”

Genome-Wide Identification, Characterization and Expression Profiling of the CONSTANS-like Genes in Potato (Solanum tuberosum L.)

“…An additional level of control influenced by the expression of StCOL1 , StSP5G and StSP6A determines whether the plant generates tubers [ 41 , 42 ]. Suppression of SlCOL1 expression in tomato leading to the promotion of fruit development was found [ 72 ]. In this study, StCOL13 was not expressed in tubers, but expressed at low levels in microtubers, and showed high expression levels in leaves.…”