CN-119193560-B - Liriodendron LCYE gene and expression protein and application thereof

Abstract

The invention discloses a tulip tree LCYE gene, an expression protein and application thereof, and relates to the technical field of plant genetic engineering. The invention discloses a tulip tree LCYE gene, which comprises LcLCYE genes, or/and LtLCYE genes, or/and variant genes LcLCYE-alpha, or/and variant genes LtLCYE-alpha, wherein the nucleotide sequences of the genes correspond to SEQ ID NO.1, 3, 5 and 7 respectively. The embodiment results of the invention show that the Liriodendron LCYE homologous protein not only has the traditional LCYE enzyme activity, but also has the LCYB enzyme activity of catalyzing lycopene to form gamma-carotene and beta-carotene, and the C-terminal structure of the Liriodendron LCYE homologous protein is necessary for the LCYE enzyme activity function, but does not influence the LCYB enzyme activity function.

Inventors

• HAO ZHAODONG
• ZHU YONGWEI
• HU LINGFENG
• CHEN JINHUI
• SHI JISEN
• CAO ZIJIAN
• Xue Guoxia

Assignees

• 南京林业大学

Dates

Publication Date

20260512

Application Date

20240819

Claims (2)

1. 1. The application of a variant gene LtLCYE-alpha with a nucleotide sequence shown as SEQ ID NO.7 in promoting lycopene to be converted into beta-carotene is provided.
2. 2. The use according to claim 1, characterized in that the specific steps comprise: 1) Constructing a prokaryotic expression vector of the variant gene LtLCYE-alpha; 2) Transforming a prokaryotic expression vector into a prokaryotic expression strain; 3) And culturing, screening and obtaining the strain with remarkably increased beta-carotene content.

Description

Liriodendron LCYE gene and expression protein and application thereof Technical Field The invention belongs to the technical field of plant genetic engineering, and particularly relates to a tulip tree LCYE gene, an expression protein thereof and application thereof. Background The flower color is an important flower character, has very important functions on reproductive ecology and species evolution of flowering plants, and is an important index for evaluating ornamental value and economic value of the plants. Anthocyanidin is a major contributor to plant flower color formation and mainly comprises three natural pigments, flavonoid, carotenoid and betalain. Among them, flavonoids and carotenoids are two large pigment groups formed by most plant colors, and widely exist in most plants to participate in the plant color forming process, so that the plant colors are various. The biosynthetic pathways for carotenoids have been well studied and are highly conserved among different plants. Among them, GGPP derived from MEP pathway is converted into red lycopene by catalytic reaction of a series of enzymes such as Phytoene Synthase (PSY), phytoene Desaturase (PDS), zeta-carotene isomerase (Z-ISO), zeta-carotene desaturase (ZDS) and carotenoid isomerase (CRTISO). Lycopene is then catalyzed as a substrate by two lycopene cyclases LCYE and LCYB, which are capable of catalyzing the formation of epsilon and beta rings at one end of lycopene, respectively. Therefore, lycopene forms epsilon-carotene under continuous catalysis of LCYE enzyme, forms gamma-carotene and beta-carotene in turn under continuous catalysis of LCYB enzyme, and forms alpha-carotene under the action of LCYE and LCYB enzyme in turn. Since carotenoids have a very important role in plant growth and development and in human health, regulatory studies on carotenoids have been concentrated mostly in plant leaves or crop roots, whereas regulatory studies in plant flower coloration are relatively few (DOI: 10.3389/fpls.2019.01017). In recent years, research on the biosynthesis regulation of carotenoids in the process of flower coloration has been a major breakthrough, but is mainly concentrated in a few herbaceous plants such as tobacco, monkey face flowers and alfalfa. In tobacco, F-box protein COI1 mediates the expression regulation of PSY, ZDS and LCYB genes in a brief introduction regulation mode, thereby affecting the beta-carotene content in petals and changing the flower color (DOI: 10.3389/fpls.2019.01017). In the Hedgehog hydnum, a tetrapeptide repeat TPR protein RCP2 can indirectly regulate and control the expression of a plurality of genes such as CRISTO, LCYB and the like, thereby changing the coloring mode of the basal part of the corolla cylinder (DOI: 10.1105/tpc.19.00755). In alfalfa, the R2R3 MYB transcription factor WP1 was able to directly up-regulate expression of LCYE and LCYB by forming MBW complexes with TT8 and WD40-1, thereby enhancing carotene synthesis in alfalfa petals, making the petals yellow (DOI: 10.1105/tpc.19.00480). The relevant results provide a new field of view for carotenoid-mediated plant petal staining studies, but far less extensive or deep than in leaves or tubers, especially for carotenoid-mediated flower variation and its related basic studies in woody plants. The genus tulip (Liriodendron) belongs to the magnolia class of plants and comprises a pair of sister tree species with interintercontinental spacing between eastern and eastern north america, i.e., tulip (l.chinense) naturally distributed in eastern asia and tulip (l.tulipifera) in eastern north america. The petals of tulip tree are green, yellow longitudinal stripes penetrate through the petals in the full-bloom stage, and an orange yellow color band is arranged near the base of the petals of tulip tree in North America, so that the petals are bright in color. Earlier studies have shown that the main accumulated pigments in the orange yellow band region of liriodendron tulipifera are carotenoids, especially carotene species including alpha-carotene and beta-carotene. However, the key gene LCYB acting on carotene synthesis remained stable and low in expression level in petals, but LCYE expression was highly correlated with coloration of the band region of tulip tree and accumulation of carotene (DOI: 10.1038/s 41438-020-0287-3). In conclusion, the LCYE gene function and the genetic regulation mechanism research are enhanced, molecular mechanisms of petal coloring and carotenoid synthesis of tulip trees are deeply known, and theoretical basis is laid for cultivating new tulip tree varieties. Therefore, the research of LCYE gene functions has important scientific and application values. Disclosure of Invention Aiming at the problems existing in the prior art, the technical problem to be solved by the invention is to provide a tulip tree LCYE gene. The invention aims to provide an expression protein of the Liriodendron LCYE gene. The invention also solves th