Current Synthetic and Systems Biology
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‘MYB-Related Protein P-Like’ is the Candidate Gene Homologus to ZmMYBIF35 R2R3-Transcription Factor in Wheat (Triticum aestivum L.) for Anythocyanin Pathway Modifications

Tayyaba Noor^* and Faisal Saeed Awan ^*Correspondence: Tayyaba Noor, Department of Biotechnology, University of Agricultural Science, Faisalabad, Pakistan, Email:

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Introduction

Anthocyanins belong to a class of flavonoids that are involved in imparting characteristic color to the plant tissues. Their production within plant cells is controlled by various developmental factors as well as environmental signals. They are involved in the number of physiological functions such as pollination, seed dispersal and induction of stress response against low temperature, pathogenic infections, nutrient deficiency and radiations.

Anthocyanins in foliage leaves are not researched enough. Chlorophylls and carotenoids contribute more towards color of foliage than anthocyanins. In leaves of a plant, the anthocyanins are believed to be responsible for the red coloration in autumn season. The green color of a leaf is only due to chlorophyll but anthocyanins play their part by letting only yellow green light to pass through and allowing the leaves to excite only to this light, since oxygen radicals are produced by excitation of chlorophyll molecules, thus the oxidative load is reduced in leaves. In foliage, these pigments are located inside the vacuoles and upper as well as lower epidermis thus explaining the diverse locations for anthocyanins.

Gould, in 2004, described in its article, that anthocyanins serve as protectants for photoliable compounds (compounds that become unstable upon exposure to light and are part of defense mechanism in a plant). Moreover, it was also explained that although anthocyanins serve as protectant for photosynthetic components but absorbing excess quantum energy from light and protecting the plant from reducing quantum efficiency, more of the photons than needed are absorbed as a result and hence, deprive chlorophyll b from necessary photons. In short, the photosynthetic efficiency is reduced. However, the gas analysis of red and green leaves of O. triangularis indicated that lower CO₂ assimilation happens in red leaves as compared to green leaves but the efficiency of photosystem II remains higher in red leaves as compared to green leaves. Moreover, red leaves were also less photo inhibited than the green ones. In another experiment, the red and green leaves of dogwood plant were exposed to white light for 30 minutes. The results showed 30 percent reduction in quantum efficiency in red leaves and 100 percent reduction in green leaves indicating the importance of anthocyanins for photosystem [1].

These pigments impart red and blue coloration when exposed to acidic and alkaline environment respectively (Figure 1).

Figure 1: Basic molecular structure of anthocyanin.

The general structure of this molecule is composed of a positive charge on its C-ring hence named as flvylium ion. Empirical formula for a general anthocyanin is C₁₅H₁₁O⁺ with a molecular weight of 207.24724 g/mol. This ion is also termed as 2-phenylchromenylium. These compounds belong to the family of phenolic compounds and are glycoside in nature hence agylcone. They are also called as phytochemicals. Anthocyanins can be grouped into two categories depending upon their nature. They are: Glycosides and acylated.

The glycosylated forms of anthocyanins are also termed as anthocyanins. Cyanidin, delphinidin, pelargonidin, peonidin, malvidin and petunidin are the most common anthocyanidins distributed in the plants. The distribution of these anthocyanidins in fruits and vegetables is 50%, 12%, 12%, 12%, 7% and 7%, respectively.

Expression of anthocyanin biosynthesis genes is highly controlled by MBW protein complex, and R2R3-MYB transcription factors having the central role in the activation of anthocyanin biosynthetic genes [2].

Transcription factors and MYB

Transcription factors play crucial part in changing or controlling the cellular processes. They can modify the complex traits of plants. The genes of transcription factors contain a number of motifs in them such as; zinc fingers, MYC, bZIP and MYB. These genes are regulated or induced by specific signals such as stress signals. Among these genes, MYB containing transcription factors are large and diverse. MYB belongs to a complex of proteins named as MBW that regulates phenylpropanoid biosynthesis pathway and are involved in epidermal cell fate. Others members of this family are; MYB, bHLH and WDR. The MYB proteins have the ability to bind to DNA thus implicating ABA response or interacting with other transcription factors. V-MYB was the first MYB gene that was identified under the category of oncogene from Zea mays (C1). The members of these genes are: c-MYB, A-MYB and B-MYB.

In Arabidopsis thaliana, 190 R2R3-MYB genes have been identified. In corn (Zea mays), 157 R2R3-MYB encoding genes were identified. In populous, 192 R2R3-MYB encoding genes and 5 3R-MYB genes were found. In soybean, 252 MYBs, including 244 R2R-MYB (2R-MYB) genes, 6 R1R2R3-MYB belonging to 3R-MYB family genes and two R0R1R2R3-MYB belonging to 4RMYB genes were identified [3].

R2R3-type MYB transcription factors

R2R3-type MYB transcription factors are mainly found in plants. The structure of this type contains 2 domains; one is N-terminal conserved MYB DNA-binding domain and the other domain is C-terminus modulator region. The C-terminus is responsible for the regulatory activity performed by the protein. The MYB-binding domain contains 4 classes of proteins that are explained in the diagram (Figure 2).

Figure 2: Structural classification of MYB protein.

MYB are essential as they are; essential for the development of plants, they are involved in determining shape of cell and petal morphogenesis, differentiation of cell and its proliferation, involved in the development of trichome and phenylpropanoid metabolism, play role in hormonal responses, help against abiotic stresses and biotic stresses and are involved in regulation of primary and secondary metabolites.

Anthocyanin production in wheat is controlled by many regulatory genes such as Pc, Pan, Pg, Plb, Pp, R, Ra, Rc controlling purple culm, purple anther, purple glume, purple leaf blade, purple pericarp, red glume, red auricle and red coleoptile respectively. In another study, two loci; Pp-D1 and Pp3 on chromosome 7D and 2A having TaPpm1 (purple percarp-MYB1) and TaPpb1 (purple pericarp-bHLH1) genes were identified in regulating anthocyanin biosynthesis in purple pericarps [4].

In Zea mays, P1 gene is responsible for the production and regulation of flavonoids (3-deoxy flavonoids) and phlobaphene pigments in floral regions. P1 binds with promoter of a1 gene and results in the production of anthocyanin biosynthetic pathway enzyme i.e., Dihydroflavonol-4-reductase (DFR). Similarly, in mays, another R2R3-transcription factor; ZmMYB-IF35 controls the accumulation of several distinct phenylpropanoids (through anthocyanin biosynthetic pathway) and phenolic compounds in maize. Herine, et al. showed that ZmMYB-IF35 is capable to activate a1 promoter through its regions outside the conserved domains and results in regulation of phenylpropanoid biosynthetic pathway. Phenylpropanoid biosynthetic pathway is a part of anthocyanin pathway in plants. This type of transcription factor was also found to be involved in controlling chilling stress in maize suggesting its strong role in the defense mechanism as well as anthocyanin pathway regulation. Therefore, in the current study, we aimed at finding a homologous protein to ZmMYBIF35 in wheat capable of regulating anthocyanin pathway [5].

Materials and Methods

Target sequence

R2R3 MYB transcription factor MYB-IF35 (Zea mays) (NP_001105092.1) protein sequence in FASTA format was obtained from NCBI (https://ncbi.nlm.nih.gov/).

BLAST analysis

The sequence was subjected to BLASTp under Triticum (taxid: 4564) taxonomy. Among maximum E-value and score proteins, ‘MYB-related protein P-like’ (Triticum dicoccoides) (XP_037430643.1) was selected with max score (247), query cover (46%), E-value (8e-79) and percent identity (69.09%).

Putative 3D model prediction

The FASTA sequence of ‘MYB-related protein P-like’ (Triticum dicoccoides) (XP_037430643.1) was search in Protein Data Bank (PDB) by uploading the NCBI ID in PDB. No results or sequence was found in PDB for the ‘MYB-related protein P-like (Triticum dicoccoides)’. So, the putative model was built through SWISS MODEL (https://swissmodel.expasy.org/interactive) by uploading the protein sequence of ‘MYB-related protein P-like’ in FASTA format from NCBI.

Validation and quality assessment of putative protein models

The putative protein models were validated by ‘VERIFY 3D’ and quality was assessed through ‘PROCHECK’ by downloading protein model files from SWISS MODEL and uploading it to ERRAT tool. Visualization of the valid and best quality model was performed using PyMoL.

Identification of physical and chemical properties

The amino acid sequence of ‘MYB-related protein P-like’ of the approved model (through SWISS MODEL) was uploaded in Expasy_ProtParam (https://web.expasy.org/protparam/) tool for the identification of physical and chemical parameters such as; molecular weight, theoretical pI, amino acid composition, atomic composition, extinction coefficient, estimated half-life, instability index, aliphatic index and grand average of hydropathicity (GRAVY) [6].

Identification of sub cellular location of ‘MYB-related protein P-like’

For identifying sub cellular location of our protein, we uploaded the amino acid sequence of our putative protein in Protcom 9.0 tool.

Secondary structure prediction

For determination of secondary structure of the MYB-related protein P-like anthocyanin transcription factor; its protein sequence in FASTA format was uploaded to PSIPRED (http://bioinf.cs.ucl.ac.uk/psipred/) and SOPMA (https://npsa-prabi.ibcp.fr/cgi-bin/npsa_automat.pl?page=/NPSA/npsa_sopma.html). Both tools accurately predict secondary structures accurately.

Transmembrane helix topology

In PSIPRED, transmembrane helix prediction is done by MEMSATSVM (http://bioinf.cs.ucl.ac.uk/psipred/) which is highly accurate predictor of transmembrane helix topology along with identification of cytosolic and extra-cellular loops present in protein structure.

GO prediction: Biological, cellular and molecular function

The physio-chemical and gene ontology properties of ‘MYBrelated protein P-like’ anthocyanin transcription factor was done by uploading the amino acid sequence of our putative protein in PSIPRED FFPred 3 tool (http://bioinf.cs.ucl.ac.uk/psipred/). The biological, cellular and molecular functions of our protein were analyzed.

Post-translational modifications: Phosphorylation, glycosylation and PEST regions present within the protein sequence were predicted by FFPred PSIPRED by uploading the amino acid sequence to PSIPRED web tool.

Protein functional residues prediction: Functional residues and available hotspots or residues in the protein were predicted through HotSpot Wizard 3 available at: https://loschmidt.chemi.muni.cz/hotspotwizard/. In this program, predictions are performed by combining the functional, evolutionary and structural data from various computational tools.

Ligand binding residues prediction: Active sites present within our protein of interest were determined by uploading sequence in FASTA format to IntFOLD server (version 7.0) (https://www.reading.ac.uk/bioinf/IntFOLD/).

Genomic assessment: Using NCBI, the gene for ‘MYB-related protein P-like’ protein was obtained through NCBI database. The gene was analyzed for locus of the gene in wheat, number of exons, gene symbol and conserved domains present in the gene sequence [7].

Results and Discussion

Validation quality assessment of putative protein models

The putative model built through SWISS MODEL. Resulted in 4 hypothetical models. The PDB files of all the models were downloaded. In order to determine the valid 3D model for ‘MYB-related protein P-like (Triticum dicoccoides), ERRAT software was used. The downloaded PDB file of model-01 constructed through SWISS MODEL was uploaded and program was made to run. The model was subjected to ‘VERIFY 3D’ (to validate the 3D structure of the hypothetical model) and ‘PROCHECK’ (to check the quality of the model and residues present in the model) (Figure 3).

Figure 3: Result of VERIFY-3D and PROCHECK of model-01.

The 3D model of model 01 was “fail” since, 68.53% of the residues have averaged 3D-1D score = 0.2 and fewer than 80% of the amino acids have scored = 0.2 in the 3D/1D profile. However, structure contained one residue Ser 90(C) in disallowed region and one residue ASP 134 (C) in generously allowed region (Figure 7).

Similarly, the downloaded PDB file of model 02 constructed through SWISS MODEL, was uploaded and program was made to run. The model was subjected to ‘VERIFY 3D’ and ‘PROCCHECK’. The 3D structure of the model was “rejected” since, 38.89% of the residues have averaged 3D-1D score = 0.2 and fewer than 80% of the amino acids have scored = 0.2 in the 3D/1D profile (Figure 4).

Figure 4: Result of VERIFY-3D and PROCHECK of model-02.

The quality of the structure determined through PROCHECK described that the structure had 4 errors and 1 warning. At least 90% of the residues should be in most favored region and no important residue in disallowed region. Some of the glycine residues were found in disallowed region (Figure 8).

Next, the downloaded PDB file of model 03 constructed through SWISS MODEL was uploaded and program was made to run. The model was subjected to ‘VERIFY 3D’ and ‘PROCCHECK’. 94% of the residues have averaged 3D-1D score = 0.2. Hence, the 3D structure was predicted to be “pass”. At least 80% of the amino acids have scored = 0.2 in the 3D/1D profile (Figure 5).

Figure 5: Result of VERIFY 3D and PROCHECK of model-03.

The Ramachandran plot, also shows no amino acid residue in disallowed region (Figure 9). However, one of the amino acid is present in generously allowed region [8].

Lastly, the downloaded PDB file of model 04 constructed through SWISS MODEL, was uploaded and program was made to run. The model was subjected to ‘VERIFY 3D’ and ‘PROCCHECK’. 77.36% of the residues have the average 3D-1D score = 0.2, so the structure model was predicted to be “not valid”. Moreover, fewer than 80% of the amino acids have the score = 0.2 in the 3D/1D profile (Figure 6).

Figure 6: Results of VERIFY 3D and PROCHECK of model-04.

Figure 7: Ramachandran plot of model-01.

Figure 8: Ramachandran plot of model-02.

Figure 9: Ramachandran plot of model-03.

The Ramachandran plot, also shows no amino acid residue in disallowed region but 7 of the amino acid are present in generously allowed region (Figure 10) [9].

Figure 10: Ramachandran plot of model-04.

Putative structure of ‘MYB-related protein’ transcription factor (Triticum dicoccoides)

The hypothetical structure of the ‘MYB-related protein P-like’ sequence (model-03) obtained by using SWISS-MODEL and validated by ERRAT, was then analyzed by using PyMOL for structural features. From the description of SWISS MODEL, it is evident that he model has 45.19% identity with the template sequence i.e., R2R3-MYB (Zea mays). The structure prediction was performed through X-ray crystallography and is of 1.68 Angstrom (Figure 11).

Figure 11: Description of predicted yet valid model-03 by SWISS MODEL.

The PDB file of model 3 was downloaded for visualization in PyMOL. Predicted structure of ‘MYB-related protein P-like’ (Triticum dicoccoides) constructed by SWISS MODEL shows that the chain is continuous since no break was noticed and the molecule consists of only one chain i.e., CHAIN-A as shown in (Figures 12-14).

Figure 12: Predicted structure of MYB-related protein Plike’ (Triticum dicoccoides) constructed by SWISS MODEL.

Figure 13: Sheaths and helixes shown by PyMoL in MYB-related protein P-like’ (Triticum dicoccoides).

Figure 14: PyMoL showing amino acid residues residing in generously allowed region of MYB-related protein P-like’ (Triticum dicoccoides) as determined by Ramachandran plot report through ERAAT, MYBrelated protein P-like’ (Triticum dicoccoides).

6 beta helix (shown by red), no sheath and 6 loops joining the helix structures (shown by green color) were found in the structure. ASN-69, ARG-67and ARG-62 are the residues that are present in generously allowed region but far away from allowed region (Figure 14) but ARG-56, ASN-43 and CYS-53 are although shown by Ramachandran plot to be in generously allowed region but they are located very near to allowed region [10].

Physical and chemical properties of ‘MYB-related protein P-like’ anthocyanin transcription factor

‘MYB-related protein P-like’ (C₁₆₁₈H₂₅₆₅N₄₇₉O₅₃₄S₁₅) is composed of 346 amino acids with molecular weight of 377752.95 and isoelectric point (PI) of 5.19. the protein is overall negatively charged with 47 negatively charged residues (Asp+Glu) and relatively less positively charged amino acids (Arg+Lys) i.e., 35. Proteins wit negative GRAVY index are hydrophilic so our protein was predicted to be hydrophilic with -0.595 GRAVY index. The protein was found to be thermally stable since its aliphatic index fall in the range of 66.5-84.33 i.e., 72.75 (Table 1 and Figure 15) [11].

Table 1: Expasy protparam ‘MYB-related protein P-like’ (Triticum dicoccoides) (XP_037430643.1).

(Here; ‘LocDBare’ scores based on query protein's homologies with proteins of known localization. ‘PotLocDBare’ scores based on homologies with proteins which locations are not experimentally known but are assumed from strong theoretical evidence. ‘Neural Nets’ are scores assigned by neural networks. ‘Pentamers’ are scores based on comparisons of pentamer distributions calculated for QUERY and DB sequences. ‘Integral’ is final scores that combine all above previous scores. The scores are renormalized to have a sum of scores for all localizations equal 3 (Nnets), 5 (PotLocDB, Pentamers) or 10 (LocDB, Integral)).

From protcom 9.0, the subcellular location of myb-related protein P-like anthocyanin transcription factor was found to be nuclear with ProtLocDB score (scores based on homologies with proteins which locations are not experimentally known but are assumed from strong theoretical evidence) of 5.0 (Figure 15).

According to the neural net scores, the protein was predicted to be “secreted to extracellular space” with scores of almost 1.0 (i.e., 0.96) [12].

Figure 15: Subcellular location of MYB-related protein P-like anthocyanin transcription factor as predicted by ProtCom 9.0.

Secondary structure prediction

Protein secondary structures predicted by SOPMA plots predicted that random coils consisted of the most significant portion of the protein (50%), alpha helix placed at second (36.99%), extended rows placed at third (8.38%) and beta turns placed at last (4.62%) (Figure 16 and Table 2). On the other hand, secondary structure prediction by PSIPRED, showed alpha helix (34%) and coils (66%) (Figure 17). PSIPRED also demonstrated the existence of small nonpolar (39%), hydrophobic (19%), polar (34%) and aromatic plus cysteine residues (6%) (Figure 18) [13].

Table 2: Calculated secondary structures by SOPMA plots.

Figure 16: SOPMA secondary structure prediction of ‘MYBrelated protein P-like’ (Parameters: window width: 17; similarity threshold: 8; the number of states: 4).

Figure 17: PSIPRED-sequence plot.

Figure 18: PSIPRED sequence plots; types of amino acids present in ‘MYB-related protein P-like anthocyanin’ transcription factor.

Transmembrane topology

Transmembrane topology prediction by PSIPRED (MEMSATSVM) showed that out of 346 amino acids present in the transcription factor, few amino acids at beginning (Met1-Lys42) of the sequence are immersed in cytoplasmic region with very few next amino acids contributing towards a transmembrane helix (Asn43-Ile58). Rest of the portion of the sequence belongs is majorly extracellular (Asn59-Cys346). No signal peptide, re-entrant helix and pore-lining helix were found in the structure. Figure 19, shows the predicted topology of the protein structure with its diagrammatic representation (Figure 20) [14].

Figure 19: Predicted transmembrane topology of MYB-related protein P-like

Figure 20: Transmembrane topology prediction by PSIPRED (MEMSAT-SVM) diagram.

GO prediction: Biological, cellular and molecular function

Gene ontology and predictors of physio chemical properties of ‘MYB-related protein P-like anthocyanin transcription factor through FFPred 3 tool predicted all GO domains i.e., biological process, molecular function predictions and cellular component predictions. Biological function of our protein was predicted to be bind regulation of RNA biosynthetic process (GO:2001141) with highest probability (0.944), regulation of gene expression (GO:0010468) with second highest probability (0.937) and cellular macromolecule biosynthetic process (GO: 0051171) with third highest probability (0.934) (Table 3). The prediction of molecular function of our putative protein confirms that it is a transcription factor for the regulation RNA biosynthesis of anthocyanin pathway [15].

Table 3: Predicted biological functions through PSIPRED (FFPred).

The protein was predicted to be a component of nucleolus (GO:0005730) with highest probability (0.696), nuclear body (GO:0016604) with second highest probability (0.662), ribonucleoprotein complex (GO:0030529) with third highest probability (0.625) and plasma membrane with least high probability (0.514) (Table 4). Molecular function of our protein was predicted to be bind to nucleic acids (GO:0003676), DNA (GO:0003677), zinc ions (GO:0008270), sequence-specific DNA binding transcription factor activity (GO:0003700), transition metal ion binding (GO:0046914), cytoskeletal protein binding (GO:0008092), nucleic acid binding transcription factor activity (GO:0001071), kinase binding (GO:0019900), catalytic activity (GO:0003824), protein heterodimerization activity (GO:0046982), actin binding (GO:0003779), RNA binding (GO:0003723), microtubule binding (GO:0008017), sequence-specific DNA binding RNA polymerase II transcription factor activity (GO:0000981) and protein kinase binding (GO:0019901) with probabilities ranging from highest to lowest respectively (Table 5).

Table 4: Predicted cellular component through PSIPRED (FFPred).

Table 5: Predicted molecular function through PSIPRED (FFPred).

However, the highest molecular function probability of ‘MYB-related protein P-like’ was predicted to be nucleic acid binding (probability; 0974).

Prediction of post-translational modifications

Phosphorylation, glycosylation and PEST regions present within the protein sequence were predicted by FFPred PSIPRED. The sequence feature map below shows the glycosylation with green lines and the line height indicates the confidence of the residue prediction. No phosphorylation was predicted onto the sequence. PEST domain in protein sequence represents sequence rich in Proline (P), Glutamic acid (E), Serine (S) and Threonine (T). These sequences are flanked by positively charges residues such as lysine (K), arginine (R) and histidine (H). PEST sequences play a role in displaying a proteolytic signal towards target protein for its degradation resulting in short intracellular half-lives. The sequence feature map of FFPred predicts presence of PEST region in our protein residing in between Pro150-Asp200 as shown in purple. Moreover, the most of the amino acids were also predicted to be glycosylated between pro150 to Asp200 (Figure 21) [16].

Figure 21: Sequence feature map depicting post translational modifications through PSIPRED (FFPred).

Protein functional residues prediction

The files of ‘MYB related protein P-like’ were imported into the HotSpot Wizard 3 server. The amino acids Ile-58, Gly-64, Leu-77, Glu-103 and Glu-34 were predicted as highly reliable and mutable residues situated at the catalytic pockets. Gly-64, Leu-77, Glu-103, Glu-34 were predicted outside the tunnel (Figure 22).

Figure 22: Prediction of 'MYB-related protein P-like' functional residues.

Predicted ligand binding residues

Active sites present within our protein of interest were determined by uploading sequence in FASTA format to IntFOLD server (version 7.0). In MYB-related protein P-like Triticum dicoccoides, amino acids at 180-198 and 225-228 were predicted to be involved in binding dopamine (DA382; DA893) and ruthenium (RU914) ligands most likely. The nature of attraction was predicted to be DNA binding (selectively and non-covalently) (GO term; 0003677) and binding to chromatin, the network of fibers of DNA, protein and sometimes RNA, that make up the chromosomes of the eukaryotic nucleus during interphase (GO term; 0003682) (Table 6).

Table 6: Predicted ligand binding residues through IntFOLD server (version 7.0).

Genomic assessment

Assessment of gene responsible for the transcription of protein sequence of our protein ‘Myb-related protein P-like’ was performed through NCBI database. The gene is located on chromosome 4B on LOC119296349 locus and contains 3 exons (Table 7 and Figure 23).

Table 7: Genomic characterization through NCBI.

Figure 23: Localization of gene responsible for MyB-related protein P-like protein on chromosome 4B of wheat.

Conserved domains

Conserved domains present within a gene allows detection of polypeptide sequences due to presence of conserved patterns and motifs. Through NCBI-conserved domain database, we found specific hits, non-specific hits and super-families of domains present within the sequence. Among specific hits, Arg-99, Thr-100, Asn-102, Glu-103, Lys-105, Asn-106, Tyr-107, Asn-109, Ser-110 and His-112 were found to be involved in playing role in DNA binding capability of ‘MYB-related protein P-like’ protein. Moreover, these nucleotides involved in transcribing these amino acids in this domain were also reported to be involved in chromatin remodeling (Transcription, DNA repair, replication and recombination) through interaction with histones. However, a total of 14 conserved domains were found in the sequence.

A total of three superfamilies PLN03212 (transcription repressor) REB1 superfamily (Myb superfamily proteins, including transcription factors and mRNA splicing factors) and SANT superfamily (DNA binding as well as capping complex) were predicted near N-terminal of sequence. Only SANT superfamily got ‘specific hits’ while other two superfamilies got ‘non-specific hits’.
In PLN0321; a transcription repressor MYB5 superfamily only one PLNO3212 domain (Transcription repressor MYB5; Provisional) was predicted that has the capability to bind to promoters of the DNA sequence and delay binding of RNA plymerases.

In REB1 superfamily, REB1, MYB_DNA-binding, MYB_DNAbind_6, SANT, SANT, My_DNA-bind_6, REB1 and SANT_TRF domains were predicted.

In SANT superfamily, MYB_DNA-binding, SANT, SANT domains were predicted. SANT superfamily domain was also found near N-terminal of the sequence which was predicted to be involved in overall DNA binding as well as capping complex (Figure 24 and Table 8). These results will help in the purification of our protein in future for its physiochemical and biological functions in wheat.

Table 8: List of conserved domain hits on MYB-related protein P-like (Triticum diccccoides) gene sequence.

Figure 24: Graphical summary of conserved domains on MYBrelated protein P-like (Triticum diccccoides) gene sequence.

Future prospects

By utilizing this study, suitable ligands can be determined through molecular docking that can be utilized in for genetic engineering of the bio-synthetic pathway of anthocyanins in wheat. The study is utilized for the isolation of predicted protein and its identification for its homologues in wheat and its role in various biochemical processes particularly anthocyanin biosynthetic pathway. Moreover, this study can also be used for enhancement of anthocyanin pathway genetically in wheat and identification of its capability to combat various environmental stresses.

Conclusion

The present study shows that hypothetical prediction of anthocyanin transcription factor is essential for its isolation, synthesis and characterization. The characterization of hypothetical transcription factor ‘MYB-related protein P-like’ in wheat (Triticum diccocoides) with maximum similarity to R2R3- Myb transcription factor in Zea mays was completed by employing various bioinformatics tools which led to the novel characterization of transcription factor. This method takes minimums time, is more cost effective and provides additional benefit for further purification and isolation of the protein of interest.

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