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Article

Identification of the 2AP Regulatory Gene CnProDH in Aromatic Coconut and Screening of Its Regulatory Factors

by
Xiwei Sun
,
Lixia Zhou
,
Jing Li
,
Jinyao Yin
,
Hao Ding
,
Xiaomei Liu
and
Yaodong Yang
*
Hainan Key Laboratory of Tropical Oil Crop Biology, Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571300, China
*
Author to whom correspondence should be addressed.
Forests 2025, 16(11), 1707; https://doi.org/10.3390/f16111707 (registering DOI)
Submission received: 30 September 2025 / Revised: 7 November 2025 / Accepted: 7 November 2025 / Published: 9 November 2025
(This article belongs to the Section Genetics and Molecular Biology)
Browse Figures
Versions Notes

Abstract

Aromatic coconut is a special variety of coconut. Its unique “pandan-like” aroma has won it great popularity among consumers, endowing it with considerable market potential. In our previous study, 2-acetyl-1-pyrroline (2AP), which serves as the main source of the “pandan-like” aroma in aromatic coconut, was found to exhibit significant variation among distinct aromatic coconut individuals. Now, the regulatory mechanism of 2AP has been clarified in fragrant rice, and the ProDH gene is the key gene for 2AP regulation. To further understand the regulation mechanism of 2AP content in aromatic coconut, we cloned and identified the CnProDH gene, the key gene of 2AP regulation in aromatic coconut. The results showed that the CnProDH gene had the typical ProDH structural domain, and its full-length sequence is 23,667 bp, containing 5 exons and a coding sequence (CDS) of 1599 bp. The CnProDH gene encodes a protein that possesses a β8α8 barrel structure, consisting of 532 amino acids (aa), with a molecular mass of 58,076.63 kDa and an isoelectric point of 7.11. To further understand the regulatory mechanism of CnProDH in aromatic coconut, we also constructed a yeast one-hybrid (Y1H) library for aromatic coconut. Through the Y1H experiment, combined with the prediction and analysis of cis-acting elements in the promoter of the CnProDH gene, three possible regulatory factors, including CnYABBY2, CnSAP8, and CnBRD3, were identified. These findings provide a molecular basis for clarifying and solving the problem of variations in 2AP content across different aromatic coconuts.

1. Introduction

Coconut (Cocos nucifera L.), a perennial monocotyledonous tree in the Arecaceae family, is divided into two morphological types: Talls and Dwarfs [1]. Typically, tall coconuts are often used as processing materials and processed into products such as coconut oil, coconut milk, and copra. Compared with tall coconuts, dwarf coconuts have higher sugar content and thinner coconut meat, and are often used as fresh fruits. Aromatic coconut is a special variety among dwarf coconuts, with a unique “pandan-like” aroma [2]. This aromatic characteristic originates from the natural compound 2-acetyl-1-pyrroline (2AP), which is highly soluble in hot water, ethanol, and ethyl ether, with an extremely low odor threshold of 0.1 part per billion [3]. 2AP is extensively present in nature and has been detected in various plants, including rice (Oryza sativa L.) [4], bread flowers (Vallaris glabra (L.) Kuntze) [5], pandan (Pandanus amaryllifolius Roxb. ex Lindl.) [6], cucumber (Cucumis sativus L.) [7], soybean (Glycine max (L.) Merr.) [8] and sorghum (Sorghum bicolor L. Moench) [9].
“Wenye No. 4” is an aromatic coconut variety selected from aromatic coconuts and is suitable for cultivation in China. “Wenye No. 4” begins to bear fruit 3–4 years after planting and reaches a stable production period by 8 years, yielding up to 120 fruits per plant annually. The base of the trees is not enlarged significantly, and both the leaves and petioles are green. Mature coconut fruits have an average weight of 870 g, an average minor diameter perimeter of 41.3 cm, and a green exocarp. Both the meat and water of aromatic coconut have a strong “pandan-like” aroma.
In our research, we measured the 2AP content using gas chromatography-mass spectrometry (GC-MS) [10], and we found that the 2AP content varies significantly among individual “Wenye No. 4” coconuts (2.14–35.35 parts per million) (Figure 1). Understanding the genetic control of this variation may be the key to genetic improvement of this commercially desirable trait.
The biosynthesis mechanism of 2AP has been clarified in fragrant rice, with 1-pyrroline-5-carboxylic acid (P5C) identified as a key precursor in 2AP synthesis [11]. The main sources of P5C in plants are the proline biosynthesis and metabolism pathways, and P5C is an important intermediate metabolite in these pathways [12]. Specifically, P5C can be synthesized from proline through the catalytic action of 1-pyrroline-5-carboxylic acid dehydrogenase (ProDH) [13]. ProDH is a flavin-dependent enzyme that requires flavin adenine dinucleotide (FAD) as a coenzyme to perform its catalytic function. It features a highly conserved β8α8 barrel structure in eukaryotes [14]. At present, it has been observed that the expression of ProDH can increase the 2AP content, as identified in exogenous proline treatment [15] and in vitro 2AP synthesis experiments [16]. However, the upstream regulatory mechanisms of ProDH remain unclear.
As reported by Wang and Reed in 1993 [17], the yeast one-hybrid (Y1H) system has evolved over the years into a pivotal technology for studying transcription factors. This method operates on the principle that transcription factors interact with gene promoters through cis-acting elements to regulate reporter gene expression, enabling the identification of upstream transcription factors for specific genes [18]. Currently, numerous transcription factors have been identified through Y1H. For example, OsARF6, a transcription factor regulating rice grain length and weight [19]; OsWRKY5, a transcription factor negatively regulating drought tolerance in rice [20]; and IbERF1 and IbERF10, transcription factors involved in the regulatory of anthocyanin synthesis in sweet potato [21].
In this study, we cloned and identified the ProDH gene in aromatic coconut, and screened for its upstream regulatory factors using Y1H technology. This study will enhance the understanding of the ProDH regulatory mechanism in aromatic coconut and facilitate solving the problem of significant differences in 2AP content among different aromatic coconut individuals.

2. Materials and Methods

2.1. Plant Materials

The coconut tissue materials used in this study were from the aromatic coconut variety “Wenye No. 4”, which was cultivated in the resource garden (Wenchang, Hainan Province, China) of Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences (110.78595° E, 19.55937° N). Samples of adult tree leaves, female flowers, male flowers, and 9-month-old pulp were collected. Subsequently, all samples were rapidly frozen with liquid nitrogen and stored at −80 °C for subsequent analysis.

2.2. Extraction of RNA and Synthesis of cDNA

After mixing the leaves, pulp, female flowers, and male flowers together, the mixture was ground into a powder in a mortar using liquid nitrogen, and RNA was extracted with the TRIzol method (Invitrogen 15596018, Guangzhou, China). Subsequently, the NanoDrop ND-2000 microvolume UV spectrophotometer (Thermo Scientific, Waltham, MA, USA)was used to test the purity and concentration of the RNA, ensuring that 1.9 ≤ OD260/OD280 ≤ 2.0 and OD260/OD230 ≥ 2.0. Finally, the RNA was reverse transcribed into cDNA using MMLV reverse transcriptase (Invitrogen 28025013, Guangzhou, China).

2.3. Gene Cloning and Identification

Protein sequences of the ProDH gene in rice and Arabidopsis (Arabidopsis thaliana (L.) Heynh.) were downloaded from the NCBI RefSeq database [22]. The reference genome of the dwarf coconut variety was obtained from the Genome Warehouse in National Genomics Data Center, Beijing Institute of Genomics, Chinese Academy of Sciences/China National Center for Bioinformation, (Accession No. GWHBEBT00000000) [23]. The coding sequence (CDS) of the CnProDH gene was acquired through BLAST (v2.15.0+) [24] alignment. Based on the obtained CDS, full-length amplification primers (Table S2) for the CnProDH gene were designed using Primer Premier 6 and Oligo 7 software. Using cDNA as template, the CnProDH gene was amplified. After that, it was detected by 1% agarose gel electrophoresis.
According to the genome annotation information of dwarf coconut, we used GSDs 2.0 [25] to visualize the gene structure of CnProDH. The physicochemical characteristics and subcellular localization of CnProDH protein were predicted using ExPASy-ProtParam (https://web.expasy.org/protparam/, accessed on 9 July 2024.) [26] and WoLF PSORT (https://wolfpsort.hgc.jp/, accessed on 9 July 2024.) [27]. Additionally, the conserved domains of the CnProDH gene and three-dimensional protein structure of the CnProDH protein were predicted using the NCBI CDD (Conserved Domain Database) [28] and SWISS-MODEL (https://swissmodel.expasy.org/, accessed on 10 July 2024.) [29] online tools.

2.4. Prediction of Cis-Acting Elements

According to the dwarf coconut genome annotation information, the upstream 2000 bp promoter sequence of the CnProDH gene was obtained, and then the cis-acting regulatory elements of the CnProDH promoter were predicted and analyzed using PlantCARE (https://bioinformatics.psb.ugent.be/webtools/plantcare/html/, accessed on 25 July 2024 [30] and Plant PAN 4.0 [31]).

2.5. Construction of Y1H Library

After amplifying cDNA using three-primer (Table S2) amplification, the cDNA was purified with DNA Clean Beads (Vazyme N411-01, Nanjing China) and Oligo (dT) magnetic beads. The cDNA was normalized using the Trimmer-2 cDNA normalization kit (Evrogen NK003, Beijing, China), and CHROMA SPIN Columns (TAKARA 636079, Beijing, China) was used to remove the primer. Afterwards, the cDNA was ligated to the pGADT7 vector using the ClonExpress® II One Step Cloning Kit (Vazyme, C112-01), and the homologous recombinant vector was precipitated at low temperature using Acryl Carrier (Solarbio SA1020, Beijing, China). Finally, the E. coli TOP10 competent cells (Shanghai Weidi Biotechnology DE1010, Shanghai, China) were transformed by electroporation and cultured in liquid SOC medium. Glycerol was added to a final concentration of 20% to obtain the library suspension.
Ten microliters (10 μL) of the library broth were diluted 10,000 times, and 100 μL of the diluted broth was coated onto LB plates containing ampicillin (Amp), followed by overnight incubation at 37 °C. The capacity (CFU) and titer (CFU/mL) of the library were calculated based on the number of colonies on the plates. Twenty-four colonies from the plates were randomly selected for colony PCR, detected them with 1.5% agarose gel electrophoresis, and the recombinant rate of the library was estimated.

2.6. Construction of Bait Vector and Self-Activation Detection

The cloned promoter sequence of CnProDH was inserted into the EcoR I/Sac I restriction enzyme sites of the pHIS2 vector to generate the Y1H bait vector. Subsequently, the bait vector was transformed into E. coli TOP10 competent cells via electroporation. Transformed cells were cultured in liquid medium, followed by PCR and sequencing verification.
The bait plasmid was transformed into the Y187 yeast strain, and then the transformed yeast was inoculated onto lysine-deficient plates containing 3-amino-1,2,4-triazole (3AT) with different concentration gradients (0, 10, 20, 30, 40, 50, 75, 100 mM) for the self-activation detection of the bait vector. Meanwhile, the yeast hybrid combination of pHIS2-p53 and pGAD53m was used as the positive control.

2.7. Screening of Library

The library was cultured in LB medium containing Amp antibiotics until OD600 = 1, and then the library plasmid was extracted using High Pure Maxi Plasmid Kit (TIANGEN DP116, Beijing, China). The library plasmid was transferred into the Y187 yeast strain, using the Y187 yeast strain containing the bait plasmid used as the recipient strain. Subsequently, the transformed Y187 yeast strain was spread on SD/-Trp/-Leu/-His + 20 mM 3-AT plates for cultivation. When positive clones grew on the plates, the positive transformants grown on the plates were picked and re-streaked on SD/-Trp/-Leu/-His + 20 mM 3-AT selection plates. Ultimately, positive monoclonal colonies were obtained.

2.8. Identification and Verification of Positive Clones

The positive monoclonal colonies growing on the plate were selected for colony PCR amplification and then sent for sequencing. The sequencing results were compared with the reference CDS of dwarf coconut using BLAST, and the gene IDs of the interacting proteins were obtained. After removing duplicate gene IDs, the monoclonal colonies corresponding to the interacting proteins were inoculated on SD/-Trp/-Leu, SD/-Trp/-Leu/-His and SD/-Trp/-Leu/- His + 20mM 3AT plates, respectively, to verify the positive clones. Finally, the interaction protein genes that had been screened were annotated and identified using the UniProt database [32].

3. Results

3.1. Cloning and Identification of the CnProDH Gene

The reported protein sequences of ProDH from rice and Arabidopsis were aligned against the CDS of dwarf coconut. Only one ProDH homolog, named CnProDH was obtained (Gene ID: AZ02G0033300.1). The full-length of CnProDH was 23,667 bp, containing 5 exons and 1599 bp CDS (Figure 2A and Table S1). The CnProDH gene was cloned based on the aromatic coconut cDNA database, and a gene band of approximately 1500 bp was detected by 1% agarose gel electrophoresis (Figure 2B). Moreover, conserved domain prediction showed that the CnProDH gene contains a typical ProDH domain (Figure 2C).
We also predicted the protein physicochemical characteristics and subcellular localization. The results showed that the number of amino acids of the CnProDH protein was 532, the molecular mass was 58,076.63 kDa, and the isoelectric point was 7.11. The results also showed that the CnProDH protein was most likely expressed in chloroplasts (Table 1). In addition, three-dimensional structure modeling (Figure 2D) showed that the CnProDH protein contains β8α8 barrel structure.

3.2. Prediction of Cis-Acting Elements in the CnProDH Promoter

According to the genome annotation, the CnProDH promoter, which is located in the 2000 bp upstream sequence of the CnProDH gene, was extracted for the prediction and analysis of cis-acting elements (Figure 3). The results showed that the CnProDH promoter contains 15 main cis-acting elements, including the abscisic acid response element (ABRE), antioxidant response element (ARE), basic helix-loop-helix element (bHLH), basic leucine zipper element (bZIP), C2H2-type zinc-finger transcription factor element, CAAT-box, G-box, MYB cis-acting element, NAC cis-acting element, TGAGG-motif (a light-responsive element), TATA box, WRKY cis-acting element, YABBY cis-acting element, and zinc finger homologous domain (ZF-HD) recognition site.

3.3. Quality Detection of Y1H Library

To explore how CnProDH functions in 2AP regulation, we constructed a Y1H library of aromatic coconut using Gateway technology. For library quality assessment, 496 clones were observed on the counting plate (Figure 4A). The calculated library capacity was 4.96 × 107, with a total clone count of 9.92 × 107. Colony PCR (Figure 4B) showed that most bands in the library ranged from 1000 to 1500 bp, and the recombination rate reached 100%. These results indicated that the library was of relatively high quality.

3.4. Bait Vector Construction and Self-Activation Detection

We cloned the CnProDH promoter and constructed it into the EcoRI/Sac I sites of the pHIS2 vector to obtain the bait vector. Sequencing and agarose gel electrophoresis experiments showed (Figure 5A) that the promoter sequence, consistent with the reference sequence, was 1712 bp in length and located at positions 74–1786 bp. In addition, no colonies grew on the plate supplemented with 20 mM 3AT in the self-activation detection experiments (Figure 5B), indicating that the HIS3 reporter gene was not activated. Therefore, we decided to perform Y1H screening at 20 mM 3AT. That means, the plates supplemented with 20 mM 3AT can be used as the selection medium for the Y1H assay.

3.5. Obtainment, Identification, and Verification of Positive Clones

There were 96 positive monoclonal colonies growing in the Y1H assays (Figure 5C). The gene sequences of these positive monoclonal colonies were amplified and sequenced, followed by performing a BLAST against the CDS in the dwarf coconut. A total of 35 different genes were obtained, including 4 secondary metabolism, 2 calmodulin, 1 photosynthetic, 7 stress response, 1 DNA synthesis, 4 RNA synthesis and assembly, 6 signal transduction and transport, 6 cell component, and 4 uncharacterized genes (Figure 5D). To verify positive clones, the monoclonal colonies containing these 35 genes were cultured on SD-Trp/-Leu, SD-Trp/-Leu/-His, and SD-Trp/-Leu/-His + 20 mM 3AT plates, and all monoclonal colonies grew normally (Figure 5E). By correlating the protein functions of these 35 genes with the promoter cis-acting element prediction analysis results, we preliminarily identified three regulatory factors (Table 2). Thus, we speculated that the expression of CnProDH may be regulated by CnYABBY2, CnSAP8, and CnBRD3.

4. Discussion

Similar to fragrant rice, aromatic coconuts have higher economic value and market potential than ordinary coconuts, owing to their unique “pandan-like” aroma. However, 2AP, the main aroma compound in aromatic coconut, varies significantly among different individuals. This situation has led to unstable fruit quality in aromatic coconut, which has negatively affected their commercial value. In order to improve the understanding of 2AP regulation in aromatic coconut, which may be the key to genetic improvement of this trait, we identified the CnProDH gene, a key gene of 2AP regulation. Meanwhile, we screened three possible regulatory factors by Y1H technology, including CnYABBY2, CnSAP8 and CnBRD3, which may regulate the expression of CnProDH.
Stress-associated proteins (SAPs) contain an AN1/A20-type zinc finger domain, which plays an important role in plant abiotic stress responses. These proteins are induced to express in the early stages of abiotic stresses, such as low temperature, high temperature, high salinity, drought, and abscisic acid treatment. SAPs can regulate gene expression under abiotic stress by playing a variety of roles such as ubiquitin ligases, redox sensors, and gene expression regulators [33]. When SAPs serve as regulatory factors, they can combine with MYB cis-acting elements upstream of genes to regulate their expression [34].
The YABBY family is a class of transcription factors unique to higher plants, named for the helix-loop-helix YABBY domain at their C-termini. It plays an important role in the establishment of plant dorsoventral polarity, plant morphogenesis and development, as well as plant hormone responses [35]. The CnProDH promoter contains 4 MYB and 3 YABBY cis-acting elements within the 74–1786 bp region (Figure 3); MYB elements are predicted to combined with SAPs, while YABBY elements bind YABBY transcription factors.
It is well known that both SAPs and YABBY transcription factors are involved in plant responses to abiotic stress, and that the ProDH gene plays an important role in proline homeostasis under abiotic stress conditions [36]. Therefore, we speculate that CnSAP8 and CnYABBY2 may serve as the regulatory factors of the CnProDH gene.
Bromodomain-containing proteins (BRDs) were first identified in Drosophila, and they can specifically recognize lysine residues in histones. It is reported that BRDs can play a key role in regulating plant development and plant responses to abiotic stresses [37]. They can recruit transcription factors and coactivators to the loci of target genes and activate RNA polymerase II to drive transcription [38]. Thus, we speculated that CnBRD3 may function as a transcriptional coactivator: it may promote the combination of transcription factors and promoter via acetylation modification, thereby regulating the expression of CnProDH gene.
In this study, we preliminarily screened three potential regulators that may combine with the CnProDH promoter. However, their specific binding sites and interaction mechanisms remain unclear. We will employ additional methods, such as electrophoretic mobility shift assay (EMSA) and Dual-Luciferase Reporter assay (Dual-LUC), to further verify these interactions.

5. Conclusions

In this study, we cloned and identified the key gene CnProDH, which regulates 2AP in aromatic coconut. The CnProDH gene has the typical ProDH structural domain, and its full-length sequence is 23,667 bp, containing 5 exons and a CDS of 1599 bp. The CnProDH gene encodes a protein that possesses a β8α8 barrel structure, consisting of 532 amino acids, with a molecular mass of 58,076.63 kDa and an isoelectric point of 7.11. In addition, we constructed a Y1H library of aromatic coconut. Through Y1H experiments, combined with the prediction and analysis of cis-acting elements in the promoter of the CnProDH gene, three possible regulatory factors, including CnYABBY2, CnSAP8, and CnBRD3, were identified. These findings provide a molecular basis for clarifying and solving the problem of variations in 2AP content across different aromatic coconuts.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/f16111707/s1, Table S1: CDS of the CnProDH gene; Table S2: Primers used in this study.

Author Contributions

Conceptualization, Y.Y. and X.S.; validation, X.S., L.Z. and J.L.; formal analysis, X.S. and L.Z.; resources, X.S. and Y.Y.; data curation, X.S., J.Y., L.Z., H.D. and X.L.; writing—original draft preparation, X.S.; writing—review and editing, Y.Y., X.S. and J.Y.; visualization, X.S. and H.D.; project administration, X.S. and J.L.; funding acquisition, Y.Y. and X.S. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the National Key Research and Development Program of China (2023YFD2200701), the Major Science and Technology Project of Hainan Province (ZDKJ2021012) and the Key Research and Development Program of Hainan Province (ZDYF2020215).

Data Availability Statement

All data and materials are available upon request from the corresponding author.

Acknowledgments

During the preparation of this manuscript, the authors used WORDVICE.AI (https://wordvice.ai/cn, accessed on 29 September 2025.) for the purposes of grammar check. The authors have reviewed and edited the output and take full responsibility for the content of this publication.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 1. The 2AP content in different individuals of “Wenye No. 4”. The vertical number represents the individual “Wenye No. 4” coconut.
Figure 1. The 2AP content in different individuals of “Wenye No. 4”. The vertical number represents the individual “Wenye No. 4” coconut.
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Figure 2. Cloning and identification of the CnProDH gene. (A) Gene structure of the CnProDH gene. (B) Agarose gel electrophoresis image of CnProDH gene cloning. (C) Conserved domain prediction of the CnProDH gene. (D) Three-dimensional structural modeling of the CnProDH protein. Blue 1–8: alpha helices in β8α8 barrel structure. Red 1–8: beta sheets in β8α8 barrel structure.
Figure 2. Cloning and identification of the CnProDH gene. (A) Gene structure of the CnProDH gene. (B) Agarose gel electrophoresis image of CnProDH gene cloning. (C) Conserved domain prediction of the CnProDH gene. (D) Three-dimensional structural modeling of the CnProDH protein. Blue 1–8: alpha helices in β8α8 barrel structure. Red 1–8: beta sheets in β8α8 barrel structure.
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Figure 3. The cis-acting elements of CnProDH promoter. At the top, the black line represents the 0–2000 bp promoter sequence upstream of the CnProDH gene (relative to the transcription start site), with a direction of 5′ to 3′; at the bottom, different colored symbols represent different cis-acting elements, and their positions are indicated on the promoter sequence. The black line in the middle are the scale marks.
Figure 3. The cis-acting elements of CnProDH promoter. At the top, the black line represents the 0–2000 bp promoter sequence upstream of the CnProDH gene (relative to the transcription start site), with a direction of 5′ to 3′; at the bottom, different colored symbols represent different cis-acting elements, and their positions are indicated on the promoter sequence. The black line in the middle are the scale marks.
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Figure 4. Quality assessment of the aromatic coconut Y1H library. (A) Colony counting plate of the Y1H library. (B) Colony PCR analysis of the Y1H library. Lanes 1–24: Y1H library colonies. Lane M: marker.
Figure 4. Quality assessment of the aromatic coconut Y1H library. (A) Colony counting plate of the Y1H library. (B) Colony PCR analysis of the Y1H library. Lanes 1–24: Y1H library colonies. Lane M: marker.
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Figure 5. The possible binding proteins of CnProDH were screened using a Y1H assay. (A) Agarose gel electrophoresis of the bait vector. Lane M: KB ladder. Lane 1: bait vector plasmid. Lane 2: bait vector plasmid digested by EcoRI and Sac I. (B) Self-activation detection of the Y1H system. The pHIS2-p53 + pGAD53m transformant served as the positive control. (C) Y1H screening plate. (D) Functions and quantities of the screened proteins. (E) Verification of positive clones.
Figure 5. The possible binding proteins of CnProDH were screened using a Y1H assay. (A) Agarose gel electrophoresis of the bait vector. Lane M: KB ladder. Lane 1: bait vector plasmid. Lane 2: bait vector plasmid digested by EcoRI and Sac I. (B) Self-activation detection of the Y1H system. The pHIS2-p53 + pGAD53m transformant served as the positive control. (C) Y1H screening plate. (D) Functions and quantities of the screened proteins. (E) Verification of positive clones.
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Table 1. Physicochemical characteristics and subcellular localization prediction of CnProDH protein.
Table 1. Physicochemical characteristics and subcellular localization prediction of CnProDH protein.
Gene NameGene IDAmino AcidsMolecular Mass/kDaIsoelectric PointSubcellular Localization 1
ChloGolgMitoNuclPlas
CnProDHAZ02G0033300.153358076.637.1182121
1 The total score for subcellular localization prediction is 14 points, and the higher the protein score, the more likely it is to be expressed at that location. Chlo: chloroplast. Golg: Golgi apparatus. Mito: Mitochondrion. Nucl: nucleus. Plas: plasma membrane.
Table 2. Information of three regulatory factors.
Table 2. Information of three regulatory factors.
Gene Name/Gene IDNumberProtein NameFunctionPossible Binding Sites
CnSAP8/
AZ05G0105480.1		23Stress-associated protein 8Involved in abiotic stress response.MYB (ACGTG)
CnYABBY2/
AZ04G0074960.2		61YABBY2Involved in establishing dorsoventral polarity, morphogenesis and development, as well as phytohormone signaling and stress response.YABBY (ATCAT; ATGAT)
CnBRD3/
AZ05G0120960.3		50Bromodomain-
containing protein 3		Involved in the regulation of plant growth, development, and stress responses as a coactivator.Lysine residues
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MDPI and ACS Style

Sun, X.; Zhou, L.; Li, J.; Yin, J.; Ding, H.; Liu, X.; Yang, Y. Identification of the 2AP Regulatory Gene CnProDH in Aromatic Coconut and Screening of Its Regulatory Factors. Forests 2025, 16, 1707. https://doi.org/10.3390/f16111707

AMA Style

Sun X, Zhou L, Li J, Yin J, Ding H, Liu X, Yang Y. Identification of the 2AP Regulatory Gene CnProDH in Aromatic Coconut and Screening of Its Regulatory Factors. Forests. 2025; 16(11):1707. https://doi.org/10.3390/f16111707

Chicago/Turabian Style

Sun, Xiwei, Lixia Zhou, Jing Li, Jinyao Yin, Hao Ding, Xiaomei Liu, and Yaodong Yang. 2025. "Identification of the 2AP Regulatory Gene CnProDH in Aromatic Coconut and Screening of Its Regulatory Factors" Forests 16, no. 11: 1707. https://doi.org/10.3390/f16111707

APA Style

Sun, X., Zhou, L., Li, J., Yin, J., Ding, H., Liu, X., & Yang, Y. (2025). Identification of the 2AP Regulatory Gene CnProDH in Aromatic Coconut and Screening of Its Regulatory Factors. Forests, 16(11), 1707. https://doi.org/10.3390/f16111707

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