SOC1 (SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1) is a flowering time regulator in plants. It belongs to the MADS-box transcription factor family and plays a crucial role in the transition from vegetative to reproductive growth in plants. SOC1 is involved in various biological processes, including flower organ development, flowering time control, and response to environmental stimuli and hormone signals. In this study, shading and application of Lorsben were used for flower induction in wax apple, and the number of leaf buds, flowers, and the rate of flowering shoots were recorded after treatment. Additionally, the existing transcriptome data of wax apple in our research group were analyzed to identify the candidate gene SsSOC1 involved in regulating flowering in wax apple. The differential expression of SsSOC1 in different stages and tissues of wax apple under shading and Lorsben treatment was studied using qPCR. The results showed that the expression of the SsSOC1 gene significantly increased in the buds, leaves, leaf tips, and petioles of wax apple treated with shading, with the highest relative expression in the leaf tips. In this study, the SsSOC1 gene from Hei Tang Ba Bi wax apple was successfully cloned, and its promoter analysis, physicochemical properties of the protein, prediction of conserved functional domains, and sequence alignment were performed using bioinformatics methods. The open reading frame of the SsSOC1 gene in wax apple was found to be 654 bp, encoding a protein of 217 amino acids. The theoretical isoelectric point of the protein was 9.37, with a molecular formula of C1076H1794N322O334S10 and a molecular weight of 24.91 kDa. The protein contained 40 positively charged amino acid residues (Lys+Arg) and 32 negatively charged amino acid residues (Asp+Glu). The protein had a fat coefficient of 80.64, a grand average of hydropathicity (GRAVY) of -0.729, and an instability coefficient of 66.17. The protein structure lacked β-folds and did not belong to secretory or membrane proteins. Subcellular localization analysis indicated that the protein was mainly present in the nucleus and belonged to an unstable hydrophilic basic protein. The SsSOC1 protein in wax apple possessed conserved domains including MADS_MEF2_like and K-Box and belonged to the MADS superfamily and K-Box superfamily. The analysis identified the amino acid positions 3 to 75 and 88 to 171 as the start and end sites of the conserved domains, respectively, conforming to the typical structural features of the MADS protein family and the K-Box family. The evolutionary tree showed the highest homology between the SsSOC1 sequence in wax apple and Syzygium oleosum. By floral dip transformation, the SsSOC1 gene was introduced into Arabidopsis, and it was found that the 35S::SsSOC1 line exhibited an early flowering phenotype and a reduced number of rosette leaves compared to the wild type. This study preliminarily elucidated the important role of the SsSOC1 gene in flowering in wax apple and attempted to reveal the intrinsic regulatory mechanism of shading-induced flowering, providing guidance for wax apple production and theoretical basis for improving out-of-season cultivation techniques.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |