A MADS-Box Gene CiMADS43 Is Involved in Citrus Flowering and Leaf Development through Interaction with CiAGL9

Abstract

MADS-box genes are involved in various developmental processes including vegetative development, flower architecture, flowering, pollen formation, seed and fruit development. However, the function of most MADS-box genes and their regulation mechanism are still unclear in woody plants compared with model plants. In this study, a MADS-box gene (CiMADS43) was identified in citrus. Phylogenetic and sequence analysis showed that CiMADS43 is a GOA-like Bsister MADS-box gene. It was localized in the nucleus and as a transcriptional activator. Overexpression of CiMADS43 promoted early flowering and leaves curling in transgenic Arabidopsis. Besides, overexpression or knockout of CiMADS43 also showed leaf curl phenotype in citrus similar to that of CiMADS43 overexpressed in Arabidopsis. Protein–protein interaction found that a SEPALLATA (SEP)-like protein (CiAGL9) interacted with CiMADS43 protein. Interestingly, CiAGL9 also can bind to the CiMADS43 promoter and promote its transcription. Expression analysis also showed that these two genes were closely related to seasonal flowering and the development of the leaf in citrus. Our findings revealed the multifunctional roles of CiMADS43 in the vegetative and reproductive development of citrus. These results will facilitate our understanding of the evolution and molecular mechanisms of MADS-box genes in citrus.

CiKN1 and CiKN6 are involved in leaf development in citrus by regulating CimiR164

“…It is strange that the VIGS phenotype of CiKN6 is similar to its overexpression. This phenomenon may be mainly due to feedback regulation caused by gene function redundancy, and it has been reported in the development of citrus leaves (Ye et al., 2021). Furthermore, these results also suggested that CiKN1 and CiKN6 may cooperate to regulate the development of citrus leaf shape, and CiKN6 plays a more important role based on the VIGS analysis.…”

“…Arabidopsis was transformed by the floral‐dip method (Clough & Bent, 1998). Agrobacterium ‐mediated lemon transformation of stem segments was performed as previously described (Fu et al., 2011; Ye et al., 2021). The positive plants were detected by PCR amplification of genomic DNA.…”

“…The A. tumefaciens GV3101 strain harboring the N‐terminal YFP‐fused and C‐terminal YFP‐fused constructs was mixed and coinfiltrated into tobacco leaves. The experimental details of the subcellular localization and BiFC assays were performed as previously described (Ye et al., 2021).…”

“…The GST protein was used as a negative control. The experiment was performed as previously described (Ye et al., 2021).…”

An Overview of the Practices and Management Methods for Enhancing Seed Production in Conifer Plantations for Commercial Use

“…The LEAFY and UFO genes have a similar function in conifers; the LEAFY gene interacts with the UFO gene by cloning and yeast two-hybrid techniques, and it is speculated that the UFO gene in Metasequoia glyptostroboides may act as a transcriptional cofactor to regulate the LEAFY gene activity and, thus, participate in the regulation of the flower meristem development [55]. MADS-box genes, a class of important transcriptional regulatory factors in eukaryotes (animals, plants and fungi), play an important role in growth and development regulation and signal transduction [56,57]. There are studies that show that three MADS-box genes (PrMADS1, PrMADS2 and PrMADS3), LEAFY/FLORICAULA and NEEDLY (NLY) were highly participated in the early stages of initiation and differentiation of P. radiata male and female cone buds, as well as vegetative buds [58].…”