Genome-wide identification and expression analyses of cytochrome P450 genes in mulberry (Morus notabilis)

Genome-wide characterization of cytochrome P450 genes reveals the potential roles in fruit ripening and response to cold stress in tomato

Plant cytochrome P450 (CYP) superfamily, the largest enzyme metabolism family, has been identified in many species and plays a vital role in plant development and stress response via secondary metabolite biosynthesis. A comprehensive identification and functional investigation of CYPs in tomato plants would contribute to deeper understanding of their biological significance. In this study, 268 tomato CYP genes were identified and found to be unevenly located on 12 chromosomes. Based on the phylogenetic analysis, these 268 SlCYPs were classed into two distinct clades (A-type and non-A-type) and nine clans, including 48 families. Moreover, 67 tandem and 22 WGD (whole genome duplication)/segmental duplication events were detected, of which 12 SlCYP genes experienced both WGD/segmental and tandem duplication events, indicating that tandem duplication plays a major role in the expansion of the SlCYP family. Besides, 48 pairs containing 41 SlCYP and 44 AtCYP genes were orthologous, while 216 orthologous pairs were obtained between tomato and potato. The expression level of all SlCYP genes in tomato tissues at different development stages was analyzed, and most expressed SlCYPs showed a tissue-specific pattern. Meanwhile, 143 differentially expressed SlCYPs were identified under cold stress. Furthermore, the RT-qPCR results indicated that SlCYPs may be involved in fruit ripening and cold tolerance in tomato seedlings. These findings provide valuable insights into the evolutionary relationships and functional characteristics of SlCYPs, which can be utilized for further investigation of fruit metabolic pathways and cold tolerance in tomato.

Genome-wide identification of the CYP82 gene family in cucumber and functional characterization of CsCYP82D102 in regulating resistance to powdery mildew

The cytochrome P450 (CYP450) gene family plays a vital role in basic metabolism, hormone signaling, and enhances plant resistance to stress. Among them, the CYP82 gene family is primarily found in dicots, and they are typically activated in response to various specific environmental stresses. Nevertheless, their roles remain considerably obscure, particularly within the context of cucumber. In the present study, 12 CYP82 subfamily genes were identified in the cucumber genome. Bioinformatics analysis included gene structure, conserved motif, cis-acting promoter element, and so on. Subcellular localization predicted that all CYP82 genes were located in the endoplasmic reticulum. The results of cis element analysis showed that CYP82s may significantly affect the response to stress, hormones, and light exposure. Expression patterns of the CYP82 genes were characterized by mining available RNA-seq data followed by qRT-PCR (quantitative real-time polymerase chain reaction) analysis. Members of CYP82 genes display specific expression profiles in different tissues, and in response to PM and abiotic stresses in this study, the role of CsCYP82D102, a member of the CYP82 gene family, was investigated. The upregulation of CsCYP82D102 expression in response to powdery mildew (PM) infection and treatment with methyl jasmonate (MeJA) or salicylic acid (SA) was demonstrated. Further research found that transgenic cucumber plants overexpressing CsCYP82D102 display heightened resistance against PM. Wild-type (WT) leaves exhibited average lesion areas of approximately 29.7% at 7 dpi upon powdery mildew inoculation. In contrast, the two independent CsCYP82D102 overexpression lines (OE#1 and OE#3) displayed significantly reduced necrotic areas, with average lesion areas of approximately 13.4% and 5.7%. Additionally, this enhanced resistance is associated with elevated expression of genes related to the SA/MeJA signaling pathway in transgenic cucumber plants. This study provides a theoretical basis for further research on the biological functions of the P450 gene in cucumber plants.

Genome-wide identification and expression profiles of the Phytophthora infestans responsive CYPome (cytochrome P450 complement) in Solanum tuberosum

Cytochrome P450s represent one of the largest protein families across all domains of life. In plants, biotic stress can regulate the expression of some P450 genes. However, the CYPome (cytochrome P450 complement) in Solanum tuberosum and its response to Phytophthora infestans infection remains unrevealed. In this study, 488 P450 genes were identified from potato genome, which can be divided into 41 families and 57 subfamilies. Responding to the infection of P. infestans, 375 potato P450 genes were expressed in late blight resistant or susceptible cultivars. A total of 14 P450 genes were identified as resistant related candidates, and 81 P450 genes were identified as late blight responsive candidates. Several phytohormone biosynthesis, brassinosteroid biosynthesis, and phenylpropanoid biosynthesis involved P450 genes were differentially expressed during the potato-pathogen interactions. This study firstly reported the CYPome in S. tuberosum, and characterized the expression patterns of these P450 genes during the infection of P. infestans.

Biosynthetic pathways and related genes regulation of bioactive ingredients in mulberry leaves

Mulberry leaves are served not only as fodder for silkworms but also as potential functional food, exhibiting nutritional and medical benefits due to the complex and diverse constituents, including alkaloids, flavonoids, phenolic acids, and benzofurans, which possess a wide range of biological activities, such as anti-diabete, anti-oxidant, anti-inflammatory, and so on. Nevertheless, compared with the well-studied phytochemistry and pharmacology of mulberry leaves, the current understanding of the biosynthesis mechanisms and regulatory mechanisms of active ingredients in mulberry leaves remain unclear. Natural resources of these active ingredients are limited owing to their low contents in mulberry leaves tissues and the long growth cycle of mulberry. Biosynthesis is emerging as an alternative means for accumulation of the desired high-value compounds, which can broaden channels for their large-scale green productions. Therefore, this review summarizes the recent research advance on the correlative key genes, enzyme biocatalytic reactions and biosynthetic pathways of valuable natural ingredients (i.e. alkaloids, flavonoids, phenolic acids, and benzofurans) in mulberry leaves, thereby offering important insights for their further biomanufacturing.

Comprehensive and evolutionary analysis of Spodoptera litura-inducible Cytochrome P450 monooxygenase gene family in Glycine max elucidate their role in defense

Plants being sessile organisms and lacking both circulating phagocytic cells and somatic adaptive immune response, have thrived on various defense mechanisms to fend off insect pests and invasion of pathogens. CYP450s are the versatile enzymes, which thwart plants against insect pests by ubiquitous biosynthesis of phytohormones, antioxidants, and secondary metabolites, utilizing them as feeding deterrents and direct toxins. Therefore, a comprehensive analysis of biotic stress-responsive CYPs from Glycine max was performed to ascertain their function against S. litura-infestation. Phylogenetic analysis and evolutionary studies on conserved domains and motifs disclosed the evolutionary correspondence of these GmCYPs with already characterized members of the CYP450 superfamily and close relatedness to Medicago truncatula. These GmCYPs were mapped on 13 chromosomes; they possess 1-8 exons; they have evolved due to duplication and are localized in endoplasmic reticulumn. Further, identification of methyl-jasmonate, salicylic acid, defense responsive and flavonoid biosynthesis regulating cis-acting elements, their interaction with biotic stress regulating proteins and their differential expression in diverse types of tissues, and during herbivory, depicted their responsiveness to biotic stress. Three-dimensional homology modelling of GmCYPs, docking with heme cofactor required for their catalytic activity and enzyme-substrate interactions were performed to understand the functional mechanism of their action. Moreover, to gain insight into their involvement in plant defense, gene expression analysis was evaluated, which revealed differential expression of 11 GmCYPs upon S. litura-infestation, 12 GmCYPs on wounding while foliar spray of ethylene, methyl-jasmonate and salicylic acid differentially regulated 11 GmCYPs, 6 GmCYPs, and 10 GmCYPs respectively. Our study comprehensively analysed the underlying mechanism of GmCYPs function during S. litura-infestation, which can be further utilized for functional characterization to develop new strategies for enhancing soybean resistance to insect pests.

Genome-wide identification, comparative analysis and functional roles in flavonoid biosynthesis of cytochrome P450 superfamily in pear (Pyrus spp.)

BACKGROUND

The cytochrome P450 (CYP) superfamily is the largest enzyme metabolism family in plants identified to date, and it is involved in many biological processes, including secondary metabolite biosynthesis, hormone metabolism and stress resistance. However, the P450 gene superfamily has not been well studied in pear (Pyrus spp.).

RESULTS

Here, the comprehensive identification and a comparative analysis of P450 superfamily members were conducted in cultivated and wild pear genomes. In total, 338, 299 and 419 P450 genes were identified in Chinese white pear, European pear and the wild pear, respectively. Based on the phylogenetic analyses, pear P450 genes were divided into ten clans, comprising 48 families. The motif and gene structure analyses further supported this classification. The expansion of the pear P450 gene family was attributed to whole-genome and single-gene duplication events. Several P450 gene clusters were detected, which have resulted from tandem and proximal duplications. Purifying selection was the major force imposed on the long-term evolution of P450 genes. Gene dosage balance, subfunctionalization and neofunctionalization jointly drove the retention and functional diversification of P450 gene pairs. Based on the association analysis between transcriptome expression profiles and flavonoid content during fruit development, three candidate genes were identified as being closely associated with the flavonoid biosynthesis, and the expression of one gene was further verified using qRT-PCR and its function was validated through transient transformation in pear fruit.

CONCLUSIONS

The study results provide insights into the evolution and biological functions of P450 genes in pear.

MsCYP71 is a positive regulator for drought resistance in alfalfa

Cytochrome P450 (CYP450) family proteins play key roles in plant growth, development, stress responses, and other physiological processes. Here, we cloned the cytochrome P450 gene MsCYP71 in alfalfa and found that the expression of MsCYP71 was induced by drought stress. Silencing the MsCYP71 gene using virus-induced gene silencing technology significantly decreased the drought resistance of alfalfa, as indicated by their lower relative water content, net photosynthetic rate, and chlorophyll fluorescence maximum (Fm); further, the heterologous overexpression of MsCYP71 in tobacco significantly enhanced the drought resistance and Fm of transgenic tobacco. Furthermore, the expression of MsCYP71 across 45 alfalfa accessions under drought stress was investigated. A significant positive correlation between drought resistance and MsCYP71 expression was observed. The 45 alfalfa accessions were clustered into four groups, and drought resistance, Fm, and MsCYP71 were higher in group I than in the other groups, indicating that group I accessions can be used as candidate germplasm resources for the breeding of drought-resistant alfalfa varieties. Overall, our findings indicated that MsCYP71 is a positive regulator of drought resistance in alfalfa, and its expression can be used to evaluate the drought resistance of alfalfa.

Genome-wide analysis of the P450 gene family in tea plant (Camellia sinensis) reveals functional diversity in abiotic stress

BACKGROUND

Cytochrome P450 (Cytochrome P450s) genes are involved in the catalysis of various reactions, including growth, development, and secondary metabolite biosynthetic pathways. However, little is known about the characteristics and functions of the P450 gene family in Camellia sinensis (C. sinensis).

RESULTS

To reveal the mechanisms of tea plant P450s coping with abiotic stresses, analyses of the tea plant P450 gene family were conducted using bioinformatics-based methods. In total, 273 putative P450 genes were identified from the genome database of C. sinensis. The results showed that P450s were well-balanced across the chromosomes I to XV of entire genome, with amino acid lengths of 268-612 aa, molecular weights of 30.95-68.5 kDa, and isoelectric points of 4.93-10.17. Phylogenetic analysis divided CsP450s into 34 subfamilies, of which CYP71 was the most abundant. The predicted subcellular localization results showed that P450 was distributed in a variety of organelles, with chloroplasts, plasma membrane,,and cytoplasm localized more frequently. The promoter region of CsP450s contained various cis-acting elements related to phytohormones and stress responses. In addition, ten conserved motifs (Motif1-Motif10) were identified in the CsP450 family proteins, with 27 genes lacking introns and only one exon. The results of genome large segment duplication showed that there were 37 pairs of genes with tandem duplication. Interaction network analysis showed that CsP450 could interact with multiple types of target genes, and there are protein interactions within the family. Tissue expression analysis showed that P450 was highly expressed in roots and stems. Moreover, qPCR analysis of the relative expression level of the gene under drought and cold stress correlated with the sequencing results.

CONCLUSIONS

This study lays the foundation for resolving the classification and functional study of P450 family genes and provides a reference for the molecular breeding of C. sinensis.

A Comprehensive Genome-Wide Investigation of the Cytochrome 71 (OsCYP71) Gene Family: Revealing the Impact of Promoter and Gene Variants (Ser33Leu) of OsCYP71P6 on Yield-Related Traits in Indica Rice (Oryza sativa L.)

The cytochrome P450 (CYP450) gene family plays a critical role in plant growth and developmental processes, nutrition, and detoxification of xenobiotics in plants. In the present research, a comprehensive set of 105 OsCYP71 family genes was pinpointed within the genome of indica rice. These genes were categorized into twelve distinct subfamilies, where members within the same subgroup exhibited comparable gene structures and conserved motifs. In addition, 105 OsCYP71 genes were distributed across 11 chromosomes, and 36 pairs of OsCYP71 involved in gene duplication events. Within the promoter region of OsCYP71, there exists an extensive array of cis-elements that are associated with light responsiveness, hormonal regulation, and stress-related signaling. Further, transcriptome profiling revealed that a majority of the genes exhibited responsiveness to hormones and were activated across diverse tissues and developmental stages in rice. The OsCYP71P6 gene is involved in insect resistance, senescence, and yield-related traits in rice. Hence, understanding the association between OsCYP71P6 genetic variants and yield-related traits in rice varieties could provide novel insights for rice improvement. Through the utilization of linear regression models, a total of eight promoters were identified, and a specific gene variant (Ser33Leu) within OsCYP71P6 was found to be linked to spikelet fertility. Additionally, different alleles of the OsCYP71P6 gene identified through in/dels polymorphism in 131 rice varieties were validated for their allelic effects on yield-related traits. Furthermore, the single-plant yield, spikelet number, panicle length, panicle weight, and unfilled grain per panicle for the OsCYP71P6-1 promoter insertion variant were found to contribute 20.19%, 13.65%, 5.637%, 8.79%, and 36.86% more than the deletion variant, respectively. These findings establish a robust groundwork for delving deeper into the functions of OsCYP71-family genes across a range of biological processes. Moreover, these findings provide evidence that allelic variation in the promoter and amino acid substitution of Ser33Leu in the OsCYP71P6 gene could potentially impact traits related to rice yield. Therefore, the identified promoter variants in the OsCYP71P6 gene could be harnessed to amplify rice yields.

The gap-free genome of mulberry elucidates the architecture and evolution of polycentric chromosomes

Mulberry is a fundamental component of the global sericulture industry, and its positive impact on our health and the environment cannot be overstated. However, the mulberry reference genomes reported previously remained unassembled or unplaced sequences. Here, we report the assembly and analysis of the telomere-to-telomere gap-free reference genome of the mulberry species, Morus notabilis, which has emerged as an important reference in mulberry gene function research and genetic improvement. The mulberry gap-free reference genome produced here provides an unprecedented opportunity for us to study the structure and function of centromeres. Our results revealed that all mulberry centromeric regions share conserved centromeric satellite repeats with different copies. Strikingly, we found that M. notabilis is a species with polycentric chromosomes and the only reported polycentric chromosome species up to now. We propose a compelling model that explains the formation mechanism of new centromeres and addresses the unsolved scientific question of the chromosome fusion-fission cycle in mulberry species. Our study sheds light on the functional genomics, chromosome evolution, and genetic improvement of mulberry species.

Genome-wide investigation of Cytochrome P450 superfamily of Aquilaria agallocha: Association with terpenoids and phenylpropanoids biosynthesis

Agarwood is a dark resinous wood, produced when Aquilaria tree responds to wounding and microbial infection resulting in the accumulation of fragrant metabolites. Sesquiterpenoids and 2-(2-phenylethyl) chromones are the major phytochemicals in agarwood and Cytochrome P450s (CYPs) are one of the important enzymes in the biosynthesis of these fragrant chemicals. Thus, understanding the repertoire of CYP superfamily in Aquilaria can not only give insights into the fundamentals of agarwood formation, but can also provide a tool for the overproduction of the aroma chemicals. Therefore, current study was designed to investigate CYPs of an agarwood producing plant, Aquilaria agallocha. We identified 136 CYP genes from A. agallocha genome (AaCYPs) and classified them into 8 clans and 38 families. The promoter regions had stress and hormone-related cis-regulatory elements which indicate their participation in the stress response. Duplication and synteny analysis revealed segmental and tandem duplicated and evolutionary related CYP members in other plants. Potential members involved in the biosynthesis of sesquiterpenoids and phenylpropanoids were identified and found to be upregulated in methyl jasmonate-induced callus and infected Aquilaria trees by real-time quantitative PCR analyses. This study highlights the possible involvement of AaCYPs in agarwood resin development and their complex regulation during stress exposure.

Molecular Characterization of an Isoflavone 2'-Hydroxylase Gene Revealed Positive Insights into Flavonoid Accumulation and Abiotic Stress Tolerance in Safflower

Flavonoids with significant therapeutic properties play an essential role in plant growth, development, and adaptation to various environments. The biosynthetic pathway of flavonoids has long been studied in plants; however, its regulatory mechanism in safflower largely remains unclear. Here, we carried out comprehensive genome-wide identification and functional characterization of a putative cytochrome P45081E8 gene encoding an isoflavone 2'-hydroxylase from safflower. A total of 15 CtCYP81E genes were identified from the safflower genome. Phylogenetic classification and conserved topology of CtCYP81E gene structures, protein motifs, and cis-elements elucidated crucial insights into plant growth, development, and stress responses. The diverse expression pattern of CtCYP81E genes in four different flowering stages suggested important clues into the regulation of secondary metabolites. Similarly, the variable expression of CtCYP81E8 during multiple flowering stages further highlighted a strong relationship with metabolite accumulation. Furthermore, the orchestrated link between transcriptional regulation of CtCYP81E8 and flavonoid accumulation was further validated in the yellow- and red-type safflower. The spatiotemporal expression of CtCYP81E8 under methyl jasmonate, polyethylene glycol, light, and dark conditions further highlighted its likely significance in abiotic stress adaption. Moreover, the over-expressed transgenic Arabidopsis lines showed enhanced transcript abundance in OE-13 line with approximately eight-fold increased expression. The upregulation of AtCHS, AtF3'H, and AtDFR genes and the detection of several types of flavonoids in the OE-13 transgenic line also provides crucial insights into the potential role of CtCYP81E8 during flavonoid accumulation. Together, our findings shed light on the fundamental role of CtCYP81E8 encoding a putative isoflavone 2'-hydroxylase via constitutive expression during flavonoid biosynthesis.

Insights into the Cytochrome P450 Monooxygenase Superfamily in Osmanthus fragrans and the Role of OfCYP142 in Linalool Synthesis

Osmanthus fragrans flowers have long been used as raw materials in food, tea, beverage, and perfume industries due to their attractive and strong fragrance. The P450 superfamily proteins have been reported to widely participate in the synthesis of plant floral volatile organic compounds (VOCs). To investigate the potential functions of P450 superfamily proteins in the fragrance synthesis of O. fragrans, we investigated the P450 superfamily genome wide. A total of 276 P450 genes were identified belonging to 40 families. The RNA-seq data suggested that many OfCYP genes were preferentially expressed in the flower or other organs, and some were also induced by multiple abiotic stresses. The expression patterns of seven flower-preferentially expressed OfCYPs during the five different flower aroma content stages were further explored using quantitative real-time PCR, showing that the CYP94C subfamily member OfCYP142 had the highest positive correlation with linalool synthesis gene OfTPS2. The transient expression of OfCYP142 in O. fragrans petals suggested that OfCYP142 can increase the content of linalool, an important VOC of the O. fragrans floral aroma, and a similar result was also obtained in flowers of OfCYP142 transgenic tobacco. Combined with RNA-seq data of the transiently transformed O. fragrans petals, we found that the biosynthesis pathway of secondary metabolites was significantly enriched, and many 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway genes were also upregulated. This evidence indicated that the OfCYP proteins may play critical roles in the flower development and abiotic response of O. fragrans, and that OfCYP142 can participate in linalool synthesis. This study provides valuable information about the functions of P450 genes and a valuable guide for studying further functions of OfCYPs in promoting fragrance biosynthesis of ornamental plants.

Genome-wide transcriptome analysis and characterization of the cytochrome P450 flavonoid biosynthesis genes in pigeon pea (Cajanus cajan)

226 CcCYP450 genes were identified at the genomic level and were classified into 45 clades based on phylogenetic analysis. CcCYP75B165 gene was found that might play important roles in the biosynthesis of flavonoids in pigeon pea, and was significantly induced by methyl jasmonate (MeJA). The cytochrome P450 mono-oxygenase (CYP450) superfamily plays a key role in the flavonoid biosynthesis pathway and resists different kinds of stresses. Several CYP450 genes have been identified to be involved in the biosynthesis of crop protection agents. However, the CcCYP450 genes from pigeon pea have not been identified. Here, 226 CcCYP450 genes were identified at the genomic level by analysing the gene structure, distribution on chromosomes, gene duplication, and conserved motifs and were classified into 45 clades based on phylogenetic analysis. RNA-seq analysis revealed clear details of CcCYP450 genes that varied with time of MeJA (methyl jasmonate) induction. Among them, six CcCYP450 subfamily genes were found that might play important roles in the biosynthesis of flavonoids in pigeon pea. The overexpression of CcCYP75B165 in pigeon pea significantly induced the accumulation of genistin and downregulated the contents of cajaninstilbene acid, apigenin, isovitexin, and genistein and the expression of flavonoid synthase genes. This study provides theoretical guidance and plant genetic resources for cultivating new pigeon pea varieties with high flavonoid contents and exploring the molecular mechanisms of the biosynthesis of flavonoids under MeJA treatment.

Comprehensive Analysis of Cytochrome P450 Monooxygenases Reveals Insight Into Their Role in Partial Resistance Against Phytophthora sojae in Soybean

Cytochrome P450 monooxygenases (P450) participate in the catalytic conversion of biological compounds in a plethora of metabolic pathways, such as the biosynthesis of alkaloids, terpenoids, phenylpropanoids, and hormones in plants. Plants utilize these metabolites for growth and defense against biotic and abiotic stress. In this study, we identified 346 P450 (GmP450) enzymes encoded by 317 genes in soybean where 26 GmP450 genes produced splice variants. The genome-wide comparison of both A-type and non-A-type GmP450s for their motifs composition, gene structure, tissue-specific expression, and their chromosomal distribution were determined. Even though conserved P450 signature motifs were found in all GmP450 families, larger variation within a specific motif was observed in the non-A-type GmP450s as compared with the A-type. Here, we report that the length of variable region between two conserved motifs is exact in the members of the same family in majority of the A-type GmP450. Analyses of the transcriptomic datasets from soybean-Phytophthora sojae interaction studies, quantitative trait loci (QTL) associated with P. sojae resistance, and co-expression analysis identified some GmP450s that may be, in part, play an important role in partial resistance against P. sojae. The findings of our CYPome study provides novel insights into the functions of GmP450s and their involvements in metabolic pathways in soybean. Further experiments will elucidate their roles in general and legume-specific function.

Assessing the Nutritional-Value-Based Therapeutic Potentials and Non-Destructive Approaches for Mulberry Fruit Assessment: An Overview

Among different fruits, mulberry is the most highlighted natural gift in its superior nutritional and bioactive composition, indispensable for continuing a healthy life. It also acts as a hepatoprotective immunostimulator and improves vision, anti-microbial, anti-cancer agent, anti-stress activity, atherosclerosis, neuroprotective functions, and anti-obesity action. The mulberry fruits also help reduce neurological disorders and mental illness. The main reason for that is the therapeutic potentials present in the nutritional components of the mulberry fruit. The available methods for assessing mulberry fruits are mainly chromatographic based, which are destructive and possess many limitations. However, recently some non-invasive techniques, including chlorophyll fluorescence, image processing, and hyperspectral imaging, were employed to detect various mulberry fruit attributes. The present review attempts to collect and explore available information regarding the nutritional and medicinal importance of mulberry fruit. Besides, non-destructive methods established for the fruit are also elaborated. This work helps encourage many more research works to dug out more hidden information about the essential nutrition of mulberry that can be helpful to resolve many mental-illness-related issues.

Comparative Proteomics of Mulberry Leaves at Different Developmental Stages Identify Novel Proteins Function Related to Photosynthesis

Mulberry leaves at different positions are different in photosynthetic rate, nutrient substance and feeding impact to silkworms. Here, we investigated the proteomic differences of the first (L1), sixth (L6), and twentieth (L20) mulberry leaves at different stem positions (from top to the base) using a label-free quantitative proteomics approach. L1 contained less developed photosynthetic apparatus but was more active in protein synthesis. L20 has more channel proteins and oxidoreductases relative to L6. Proteins that detected in all measured leaves were classified into three groups according to their expression patterns in L1, L6, and L20. The protein group that displayed the maximum amount in L6 has the highest possibility that function related to photosynthesis. Nine function unknown proteins belong to this group were further analyzed in the light responsive expression, evolutionary tree and sub-cellular localization analysis. Based on the results, five proteins were suggested to be involved in photosynthesis. Taken together, these results reveal the molecular details of different roles of mulberry leaves at different developmental stages and contribute to the identification of five proteins that might function related to photosynthesis.

PagWOX11/12a activates PagCYP736A12 gene that facilitates salt tolerance in poplar

The WUSCHEL-related homeobox (WOX) transcription factors WOX11 and WOX12 regulate adventitious rooting and responses to stress. The underlying physiological and molecular regulatory mechanisms in salt stress tolerance remain largely unexplored. Here, we characterized the roles of PagWOX11/12a from 84K poplar (Populus alba × P. glandulosa) and the underlying regulatory mechanism in salt stress. PagWOX11/12a was strongly induced by salt stress in roots. Overexpression of PagWOX11/12a in poplar enhanced salt tolerance, as evident by the promotion of growth-related biomass. In contrast, salt-treated PagWOX11/12a dominant repression plants displayed reduced biomass growth. Under salt stress conditions, PagWOX11/12a-overexpressed lines showed higher reactive oxygen species (ROS) scavenging capacity and lower accumulation of hydrogen peroxide (H₂ O₂ ) than non-transgenic 84K plants, whereas the suppressors displayed the opposite phenotype. In addition, PagWOX11/12a directly bound to the promoter region of PagCYP736A12 and regulated PagCYP736A12 expression. The activated PagCYP736A12 could enhance ROS scavenging, thus reducing H₂ O₂ levels in roots under salt stress in PagWOX11/12a-overexpressed poplars. The collective results support the important role of PagWOX11/12a in salt acclimation of poplar trees, indicating that PagWOX11/12a enhances salt tolerance through modulation of ROS scavenging by directly regulating PagCYP736A12 expression in poplar.

Identification of BR biosynthesis genes in cotton reveals that GhCPD-3 restores BR biosynthesis and mediates plant growth and development

Brassinosteroid (BR) synthesis genes in different cotton species was comprehensively identified, and the participation of GhCPD-3 in the BR synthesis signaling pathway for regulating plant development was verified. Brassinosteroid is a natural steroidal phytohormone that plays fundamental roles in plant growth and development. In cotton, detailed characterization and functional validation of BR biosynthesis genes remain rare. Here, 16, 8 and 9 BR biosynthesis genes were identified in Gossypium hirsutum, Gossypium raimondii and Gossypium arboreum, respectively, and their phylogenetic relationships, gene structures, conserved motifs of the encoded proteins, chromosomal locations were determined and a synteny analysis was performed. Gossypium hirsutum and Arabidopsis BR biosynthesis genes closely clustered in the phylogenetic tree and fragment duplication was likely the primary cause promoting gene family expansion in G. hirsutum. Gene Ontology (GO) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis showed their relevance as BR biosynthesis genes. GhCPD-3 was highly expressed in roots and stems and the loci of single nucleotide polymorphisms (SNPs) were significantly associated with these traits.Ectopic overexpression of GhCPD-3 in the cpd91 Arabidopsis mutant rescued the mutant phenotype by increasing plant height and leaf size in comparison to those of cpd91 and WT plants. Moreover, overexpressed GhCPD-3 in cpd91 mutants showed greater hypocotyl and root lengths than those of cpd91 and WT plants under light and dark conditions, respectively, indicating that BR actively promotes hypocotyl and root growth. Similar to CPD (CONSTITUTIVE PHOTOMORPHOGENIC DWARF), GhCPD-3 restores BR biosynthesis thereby mediating plant growth and development.

Identification and expression profile of the soil moisture and Ralstonia solanacearum response CYPome in ginger (Zingiber officinale)

Background

Cytochrome P450s play crucial roles in various biosynthetic reactions. Ginger (Zingiber officinale), which is often threatened by Ralstonia solanacearum, is the most economically important crop in the family Zingiberaceae. Whether the cytochrome P450 complement (CYPome) significantly responds to this pathogen has remained unclear.

Methods

Transcriptomic responses to R. solanacearum and soil moisture were analyzed in ginger, and expression profiles of the CYPome were determined based on transcriptome data.

Results

A total of 821 P450 unigenes with ORFs ≥ 300 bp were identified. Forty percent soil moisture suppressed several key P450 unigenes involved in the biosynthesis of flavonoids, gingerols, and jasmonates, including unigenes encoding flavonoid 3'-hydroxylase, flavonoid 3',5'-hydroxylase, steroid 22-alpha-hydroxylase, cytochrome P450 family 724 subfamily B polypeptide 1, and allene oxide synthase. Conversely, the expression of P450 unigenes involved in gibberellin biosynthesis and abscisic acid catabolism, encoding ent-kaurene oxidase and abscisic acid 8'-hydroxylase, respectively, were promoted by 40% soil moisture. Under R. solanacearum infection, the expression of P450 unigenes involved in the biosynthesis of the above secondary metabolites were changed, but divergent expression patterns were observed under different soil moisture treatments. High moisture repressed expression of genes involved in flavonoid, brassinosteroid, gingerol, and jasmonate biosynthesis, but promoted expression of genes involved in GA anabolism and ABA catabolism. These results suggest possible mechanisms for how high moisture causes elevated susceptibility to R. solanacearum infection.

Comparative transcriptomics of leaves of five mulberry accessions and cataloguing structural and expression variants for future prospects

Bombyx mori, a monophagous insect, prefers leaves of the certain species of Morus more than others. The preference has been attributed to morphological and anatomical features and biochemical compounds. In the present manuscript a comparison has been made among the transcriptome of leaves of the two preferred cultivated varieties and three wild types species. While assembling, high quality transcriptomes of five genotypes were constructed with a total of 100930, 151245, 89724, 181761 and 102908 transcripts from ML, MN, MS, K2 and V1 samples respectively. Further, to compare them, orthologs were identified from these assembled transcriptome. A total of 22462, 23413, 23685, 24371, 18362, 22326, 20058, 18049, 17567 and 20518 clusters of orthologs were found in one to one comparison in KvsN, KvsL, KvsS, KvsV, LvsN, LvsS, LvsV, NvsS, NvsV, and SvsV respectively. 4236 orthologs with algebraic connectivity of 1.0 were then used to compare and to find out differentially expressed transcripts from all the genotypes. A total of 1037 transcripts expressed that include some of the important morphology, anatomy and biochemical pathways regulating transcription factors (AP2/ERFs and C2H2 Zinc fingers) and signalling components were identified to express differentially. Further, these transcriptomes were used find out markers (SSR) and variants and a total of 1101013, 537245, 970877, 310437, 675772, 338400, 581189, 751477, 514999 and 257107 variants including SNP, MNP, Insertions and deletions were found in one to one comparisons. Taken together, our data could be highly useful for mulberry community worldwide as it could be utilized in mulberry breeding programs.

Genome-Wide Identification of Brassinosteroid Signaling Downstream Genes in Nine Rosaceae Species and Analyses of Their Roles in Stem Growth and Stress Response in Apple

Brassinosteroid signaling downstream genes regulate many important agronomic traits in rice. However, information on such genes is limited in Arabidopsis and Rosaceae species. We identified these genes in Arabidopsis and nine Rosaceae species. They were, respectively, named based on chromosomal locations. Segmental duplication and whole-genome duplication under purifying selection, as determined by Ka/Ks analysis, likely contributed to Rosaceae gene expansion. Apple (Malus domestica), Arabidopsis, and rice genes were generally similar, while several Rosaceae genes differed from their rice homologs in various characteristics, such as gene length, subcellular localization, transmembrane topology, conserved domains, secondary structures, and responses to external signals. The brassinosteroid downstream genes in apple were, respectively, induced or repressed by five phytohormones. Furthermore, these apple downstream genes were differentially expressed in different apple grafting combinations (“Nagafu No. 2”/“Malling 9” and “Nagafu No. 2”/“Nagafu No. 2”) and long–short shoot varieties (“Yanfu No. 6” and “Nagafu No. 2”). Responses of the MdBZR genes to diverse stress signals were examined and candidate hub genes were identified. These findings indicated that several brassinosteroid signaling downstream genes in Rosaceae functionally differed from their rice homologs, and certain apple genes may play roles in plant height and stress responses. This study provided valuable information and presented enriched biological theories on brassinosteroid signaling downstream genes in apple. Identification of such genes serve to help expand apple breeding and growth. This study provides useful information for brassinosteroid signaling downstream genes.

Transcriptome-wide identification, characterization, and phylogenomic analysis of cytochrome P450s from Nothapodytes nimmoniana reveal candidate genes involved in the camptothecin biosynthetic pathway

The plant Nothapodytes nimmoniana is an important source of camptothecin (CPT), an anticancer compound widely used in the treatment of colorectal, lung, and ovarian cancers. CPT is biosynthesized by the combination of the seco-iridoid and indole pathways in plants. The majority of the biosynthetic steps and associated genes still remain unknown. Certain reactions in the seco-iridoid pathway are catalyzed by cytochrome P450 enzymes. Hence, identifying transcriptionally active cytochrome P450 genes becomes essential in the elucidation of the CPT biosynthetic pathway. Here, we report the identification of 94 cytochrome P450s from the assembled transcriptomic data from leaf and root tissues of N. nimmoniana. The identified cytochrome P450 genes were full length and possessed all four conserved characteristic signature motifs of cytochrome P450 genes. Phylogenetic analysis of the protein sequences revealed their evolution and diversification and further categorized them into A-type (52.12%) and non-A-type (47.87%) cytochrome P450s. These 94 sequences represent 38 families and 63 subfamilies of cytochrome P450s. We also compared the transcriptional activity of identified cytochrome P450s with the expression of their homologs in the CPT-producing plant Ophiorrhiza pumila. Based on expression profiles and quantitative PCR validation, we propose NnCYP81CB1 and NnCYP89R1 as candidate cytochrome P450 genes involved in camptothecin biosynthesis in N. nimmoniana.

The Cytochrome P450 Monooxygenase Inventory of Grapevine (Vitis vinifera L.): Genome-Wide Identification, Evolutionary Characterization and Expression Analysis

The cytochrome P450 (CYP) monooxygenase superfamily, belonging to heme-thiolate protein products, plays a vital role in metabolizing physiologically valuable compounds in plants. To date, CYP superfamily genes have not yet been characterized in grapevine (V. vinifera L.), and their functions remain unclear. In this study, a sum of 236 VvCYPs, divided into 46 families and clustered into nine clans, have been identified based on bioinformatics analyses in grapevine genome. The characteristics of both exon-intron organizations and motif structures further supported the close evolutionary relationships of VvCYP superfamily as well as the reliability of phylogenetic analysis. The gene number-based hierarchical cluster of CYP subfamilies of different plants demonstrated that the loss of CYP families seems to be limited to single species or single taxa. Promoter analysis elucidated various cis-regulatory elements related to phytohormone signaling, plant growth and development, as well as abiotic/biotic stress responses. The tandem duplication mainly contributed to the expansion of the VvCYP superfamily, followed by singleton duplication in grapevine. Global RNA-sequencing data of grapevine showed functional divergence of VvCYPs as diverse expression patterns of VvCYPs in various organs, tissues, and developmental phases, which were confirmed by quantitative real-time reverse transcription PCR (qRT-PCR). Taken together, our results provided valuable inventory for understanding the classification and biological functions of the VvCYPs and paved the way for further functional verification of these VvCYPs and are helpful to grapevine molecular breeding.

Transcriptomic comparison between developing seeds of yellow- and black-seeded Brassica napus reveals that genes influence seed quality

BACKGROUND

Brassica napus is of substantial economic value for vegetable oil, biofuel, and animal fodder production. The breeding of yellow-seeded B. napus to improve seed quality with higher oil content, improved oil and meal quality with fewer antinutrients merits attention. Screening the genes related to this phenotype is valuable for future rapeseed breeding.

RESULTS

A total of 85,407 genes, including 4317 novel genes, were identified in the developing seeds of yellow- and black-seeded B. napus, and yellow rapeseed was shown to be an introgression line between black-seeded B. napus and yellow-seeded Sinapis alba. A total of 15,251 differentially expressed genes (DEGs) were identified among all the libraries, and 563 and 397 common DEGs were identified throughout black and yellow seed development, including 80 upregulated and 151 downregulated genes related to seed development and fatty acid accumulation. In addition, 11 up-DEGs and 31 down-DEGs were identified in all developmental stages of yellow rapeseed compared with black seed. Enrichment analysis revealed that many DEGs were involved in biosynthetic processes, pigment metabolism, and oxidation-reduction processes, such as flavonoid and phenylpropanoid biosynthesis, phenylalanine metabolism, flavone and flavonol biosynthesis, and fatty acid biosynthesis and metabolism. We found that more than 77 DEGs were related to flavonoid and lignin biosynthesis, including 4CL, C4H, and PAL, which participated in phenylalanine metabolism, and BAN, CHI/TT5, DFR, F3H, FLS, LDOX, PAP, CHS/TT4, TT5, bHLH/TT8, WD40, MYB, TCP, and CYP, which were involved in flavonoid biosynthesis. Most of these DEGs were downregulated in yellow rapeseed and were consistent with the decreased flavonoid and lignin contents. Both up- and down-DEGs related to fatty acid biosynthesis and metabolism were also analyzed, which could help to explain the improved oil content of yellow rapeseed.

CONCLUSION

This research provided comprehensive transcriptome data for yellow-seeded B. napus with a unique genetic background, and all the DEGs in comparison with the black-seeded counterpart could help to explain seed quality differences, such as lower pigmentation and lignin contents, and higher oil content.

Knockdown of Cytochrome P450 Genes Gh_D07G1197 and Gh_A13G2057 on Chromosomes D07 and A13 Reveals Their Putative Role in Enhancing Drought and Salt Stress Tolerance in Gossypium hirsutum

We identified 672, 374, and 379 CYPs proteins encoded by the CYPs genes in Gossypium hirsutum, Gossypium raimondii, and Gossypium arboreum, respectively. The genes were found to be distributed in all 26 chromosomes of the tetraploid cotton, with chrA05, chrA12, and their homeolog chromosomes harboring the highest number of genes. The physiochemical properties of the proteins encoded by the CYP450 genes varied in terms of their protein lengths, molecular weight, isoelectric points (pI), and even grand hydropathy values (GRAVY). However, over 99% of the cotton proteins had GRAVY values below 0, which indicated that the majority of the proteins encoded by the CYP450 genes were hydrophilic in nature, a common property of proteins encoded by stress-responsive genes. Moreover, through the RNA interference (RNAi) technique, the expression levels of Gh_D07G1197 and Gh_A13G2057 were suppressed, and the silenced plants showed a higher concentration of hydrogen peroxide (H₂O₂) with a significant reduction in the concentration levels of glutathione (GSH), ascorbate peroxidase (APX), and proline compared to the wild types under drought and salt stress conditions. Furthermore, the stress-responsive genes 1-Pyrroline–5-Carboxylate Synthetase (GhP5CS), superoxide dismutase (GhSOD), and myeloblastosis (GhMYB) were downregulated in VIGS plants, but showed upregulation in the leaf tissues of the wild types under drought and salt stress conditions. In addition, CYP450-silenced cotton plants exhibited a high level of oxidative injury due to high levels of oxidant enzymes, in addition to negative effects on CMS, ELWL, RLWC, and chlorophyll content The results provide the basic foundation for future exploration of the proteins encoded by the CYP450 genes in order to understand the physiological and biochemical mechanisms in enhancing drought and salt stress tolerance in plants.

Phylogenomic analysis of cytochrome P450 multigene family and their differential expression analysis in Solanum lycopersicum L. suggested tissue specific promoters

Background

Cytochrome P450 (P450) is a functionally diverse and multifamily class of enzymes which catalyses vast variety of biochemical reactions. P450 genes play regulatory role in growth, development and secondary metabolite biosynthesis. Solanum lycopersicum L. (Tomato) is an economically important crop plant and model system for various studies with massive genomic data. The comprehensive identification and characterization of P450 genes was lacking. Probing tomato genome for P450 identification would provide valuable information about the functions and evolution of the P450 gene family.

Results

In the present study, we have identified 233 P450 genes from tomato genome along with conserved motifs. Through the phylogenetic analysis of Solanum lycopersicum P450 (SlP450) protein sequences, they were classified into two major clades and nine clans further divided into 42 families. RT-qPCR analysis of selected six candidate genes were corroborated with digital expression profile. Out of 233 SlP450 genes, 73 showed expression evidence in 19 tissues of tomato. Out of 22 intron gain/loss positions, two positions were conserved in tomato P450 genes supporting intron late theory of intron evolution in SlP450 families. The comparison between tomato and other related plant P450s families showed that CYP728, CYP733, CYP80, CYP92, CYP736 and CYP749 families have been evolved in tomato and few higher plants whereas lost from Arabidopsis. The global promoter analysis of SlP450 against all the protein coding genes, coupled with expression data, revealed statistical overrepresentation of few promoter motifs in SlP450 genes which were highly expressed in specific tissue of tomato. Hence, these identified promoter motifs can be pursued further as tissue specific promoter that are driving expression of respective SlP450.

Conclusions

The phylogenetic analysis and expression profiles of tomato P450 gene family offers essential genomic resource for their functional characterization. This study allows comparison of SlP450 gene family with other Solanaceae members which are also economically important and attempt to classify functionally important SlP450 genes into groups and families. This report would enable researchers working on Tomato P450 to select appropriate candidate genes from huge repertoire of P450 genes depending on their phylogenetic class, tissue specific expression and promoter prevalence.

Electronic supplementary material

The online version of this article (10.1186/s12864-019-5483-x) contains supplementary material, which is available to authorized users.

Genome-wide identification and expression analysis of brassinosteroid biosynthesis and metabolism genes regulating apple tree shoot and lateral root growth

In plants, brassinosteroid biosynthesis and metabolism genes affect endogenous brassinosteroid metabolic processes as well as stem and root growth. However, there is little information available regarding these genes in apple. In this study, 22 brassinosteroid biosynthesis and metabolism genes were identified in apple (Malus domestica). These genes were named according to their chromosomal locations and the Arabidopsis thaliana homologs. Their conserved characteristic domains, evolutionary relationships, syntenic relationships, chemical characteristics, gene/protein structures, interactions among the encoded proteins, promoter sequences, and functions were investigated. These 22 genes were clustered with their A. thaliana homologs based on bioinformatics analyses, which suggested they are functionally similar in apple and A. thaliana. Tissue-specific expression levels revealed that most of these genes are important for stem growth and development, while several of these genes affect lateral root formation. The transcription patterns of these genes in shoot tips were investigated following diverse treatments [brassinosteroid (shoot tips and roots), brassinazole, auxin, and temperature]. Gene expression levels were also examined in different grafting combinations ('Nagafu No. 2'/Malling 9 and 'Nagafu No. 2'/'Nagafu No. 2') and shoot varieties ('Yanfu No. 6' and 'Nagafu No. 2'). The results indicated that these genes may be involved in apple stem and root growth. The comprehensive genome-wide analysis of brassinosteroid biosynthesis and metabolism genes presented herein may be useful for breeding new apple cultivars with increased vigor. The data also represent a rich genetic resource for future apple gene functional investigations that may have implications for the genetic improvement of apple tree species.

Transcriptome Analysis Reveals genes involved in flavonoid biosynthesis and accumulation in Dendrobium catenatum From Different Locations

In this study, we applied transcriptome and UHPLC-MS technologies to investigate the flavonoids and their biosynthesis- and accumulation-related genes in Dendrobium catenatum from three different locations. Eight flavonoid glycosides were identified using standard references or previously isolated substances with MS data analysis. The total flavonoid contents were determined by reagents, and all the data were analyzed. In total, 23139 unigenes were obtained using the Dendrobium catenatum genome data. Of these, 10398 were annotated in the Gene Ontology (GO) database, 4203 were annotated in the KEGG database, and 10917 were annotated in the EuKaryotic Orthologous Groups (KOG) database. Thirty-one of the unigenes annotated by the KEGG database were involved in flavonoid pathways. The genes involved in bio-modification, accumulation, transportation and the regulation of the flavonoid bio-synthesis process were investigated. In conclusion, the flavonoids in Dendrobium catenatum from three different locations were different in quantitative and qualitative which may contribute to the establishment of quality control method for this herbal plant. These differences were determined by flavonoids biosynthesis process and they were concluded by sorting out the expression level of certain biosynthesis related genes.

Transcriptome Analysis Reveals genes involved in flavonoid biosynthesis and accumulation in Dendrobium catenatum From Different Locations

In this study, we applied transcriptome and UHPLC-MS technologies to investigate the flavonoids and their biosynthesis- and accumulation-related genes in Dendrobium catenatum from three different locations. Eight flavonoid glycosides were identified using standard references or previously isolated substances with MS data analysis. The total flavonoid contents were determined by reagents, and all the data were analyzed. In total, 23139 unigenes were obtained using the Dendrobium catenatum genome data. Of these, 10398 were annotated in the Gene Ontology (GO) database, 4203 were annotated in the KEGG database, and 10917 were annotated in the EuKaryotic Orthologous Groups (KOG) database. Thirty-one of the unigenes annotated by the KEGG database were involved in flavonoid pathways. The genes involved in bio-modification, accumulation, transportation and the regulation of the flavonoid bio-synthesis process were investigated. In conclusion, the flavonoids in Dendrobium catenatum from three different locations were different in quantitative and qualitative which may contribute to the establishment of quality control method for this herbal plant. These differences were determined by flavonoids biosynthesis process and they were concluded by sorting out the expression level of certain biosynthesis related genes.

Discovery of MicroRNAs and Their Target Genes Related to Drought in Paulownia "Yuza 1" by High-Throughput Sequencing

Understanding the role of miRNAs in regulating the molecular mechanisms responsive to drought stress was studied in Paulownia "yuza 1." Two small RNA libraries and two degradome libraries were, respectively, constructed and sequenced in order to detect miRNAs and their target genes associated with drought stress. A total of 107 miRNAs and 42 putative target genes were identified in this study. Among them, 77 miRNAs were differentially expressed between drought-treated Paulownia "yuza 1" and the control (60 downregulated and 17 upregulated). The predicted target genes were annotated using the GO, KEGG, and Nr databases. According to the functional classification of the target genes, Paulownia "yuza 1" may respond to drought stress via plant hormone signal transduction, photosynthesis, and osmotic adjustment. Furthermore, the expression levels of seven miRNAs (ptf-miR157b, ptf-miR159b, ptf-miR398a, ptf-miR9726a, ptf-M2153, ptf-M2218, and ptf-M24a) and their corresponding target genes were validated by quantitative real-time PCR. The results provide relevant information for understanding the molecular mechanism of Paulownia resistance to drought and reference data for researching drought resistance of other trees.

Identification and Expression Profile of CYPome in Perennial Ryegrass and Tall Fescue in Response to Temperature Stress

Plant cytochrome P450s are involved in a wide range of biosynthetic reactions that generate various biomolecules, including a variety of defensive compounds. Perennial ryegrass (Lolium perenne) and tall fescue (Festuca arundinacea) are two major species of turf and forage grasses that usually experience low temperature below -10°C and high temperature over 38°C around the world. In this study, we re-analyzed transcriptome of perennial ryegrass and tall fescue treated with heat and cold stress. Thus, we can evaluate P450 composition in these species and confirm whether P450 genes response to temperature stress. We identified 277 and 319 P450 transcripts with open reading frames larger than 300 bp, respectively. These P450 transcripts were mainly classed in the CYP71, 51, 94, 89, 72, and 734 families. In perennial ryegrass and tall fescue, a total of 66 and 62 P450 transcripts were up-regulated, and 65 and 117 transcripts were down-regulated when subjected to heat stress, respectively. When exposed to cold stress, 60 and 73 transcripts were up-regulated, and 59 and 77 transcripts were down-regulated in perennial ryegrass and tall fescue. Among these differentially expressed transcripts, 64 and 87 of them showed expression level changes that followed the same trend, and these temperature-responsive genes primarily belong to the CYP71, 72 and 99 families. Besides, heat and cold stress altered phenylalanine and brassinosteroid involved P450 transcripts in perennial ryegrass and tall fescue. P450 transcripts involved in the metabolism of these compounds showed a strong response to heat and/or cold stress, indicating that they likely play important roles in temperature acclimation in these two species. The CYPome provide a genetic base for the future functional studies, as well as genetic studies that may improve stress tolerance for perennial ryegrass and tall fescue to extreme temperature.

Genome-Wide Identification and Characterization of Long Non-Coding RNAs from Mulberry (Morus notabilis) RNA-seq Data

Numerous sources of evidence suggest that most of the eukaryotic genome is transcribed into protein-coding mRNAs and also into a large number of non-coding RNAs (ncRNAs). Long ncRNAs (lncRNAs), a group consisting of ncRNAs longer than 200 nucleotides, have been found to play critical roles in transcriptional, post-transcriptional, and epigenetic gene regulation across all kingdoms of life. However, lncRNAs and their regulatory roles remain poorly characterized in plants, especially in woody plants. In this paper, we used a computational approach to identify novel lncRNAs from a published RNA-seq data set and analyzed their sequences and expression patterns. In total, 1133 novel lncRNAs were identified in mulberry, and 106 of these lncRNAs displayed a predominant tissue-specific expression in the five major tissues investigated. Additionally, functional predictions revealed that tissue-specific lncRNAs adjacent to protein-coding genes might play important regulatory roles in the development of floral organ and root in mulberry. The pipeline used in this study would be useful for the identification of lncRNAs obtained from other deep sequencing data. Furthermore, the predicted lncRNAs would be beneficial towards an understanding of the variations in gene expression in plants.