Functional characterization of serine proteinase inhibitor Kazal-Type in the red claw crayfish Cherax quadricarinatus

Serine protease inhibitors Kazal type (SPINKs) function in physiological and immunological processes across multicellular organisms. In the present study, we identified a SPINK gene, designated as CqSPINK, in the red claw crayfish Cherax quadricarinatus, which is the ortholog of human SPINK5. The deduced CqSPINK contains two Kazal domains consisting of 45 amino acid residues with a typical signature motif C-X3-C-X5-PVCG-X5-Y-X3-C-X6-C-X12-14-C. Each Kazal domain contains six conserved cysteine residues forming three pairs of disulfide bonds, segmenting the structure into three rings. Phylogenetic analysis revealed CqSPINK as a homolog of human SPINK5. CqSPINK expression was detected exclusively in hepatopancreas and epithelium, with rapid up-regulation in hepatopancreas upon Vibrio parahaemolyticus E1 challenge. Recombinant CqSPINK protein (rCqSPINK) was heterologously expressed in Escherichia coli and purified for further study. Proteinase inhibition assays demonstrated that rCqSPINK could potently inhibit proteinase K and subtilisin A, weakly inhibit α-chymotrypsin and elastase, but extremely weak inhibit trypsin. Furthermore, CqSPINK inhibited bacterial secretory proteinase activity from Bacillus subtilis, E. coli, and Staphylococcus aureus, and inhibited B. subtilis growth. These findings suggest CqSPINK's involvement in antibacterial immunity through direct inhibition of bacterial proteases, contributing to resistance against pathogen invasion.

Genome-wide identification, evolution of DNA methyltransferases and their expression under salinity stress in Larimichthys crocea

DNA methyltransferases (Dnmts) are responsible for DNA methylation which influences patterns of gene expression and plays a crucial role in response to environmental changes. In this study, 7 LcDnmt genes were identified in the genome of large yellow croaker (Larimichthys crocea). The comprehensive analysis was conducted on gene structure, protein and location site of LcDnmts. LcDnmt proteins belonged to three groups (Dnmt1, Dnmt2, and Dnmt3) according to their conserved domains and phylogenetic analysis. Although Dnmt3 can be further divided into three sub groups (Dnmt3a, Dnmt3b, and Dnmt3l), there is no Dnmnt3l member in the large yellow croaker. Phylogenetic analysis revealed that the Dnmt family was highly conserved in teleosts. Expression patterns derived from the RNA-seq, qRT-PCR and Western blot analysis revealed that 2 LcDnmt genes (LcDnmt1 and LcDnmt3a2) significantly regulated under salinity stress in the liver, which was found to be dominantly expressed in the intestine and brain, respectively. These two genes may play an important role in the salinity stress of large yellow croaker and represent candidates for future functional analysis. Our results revealed the conservation of Dnmts during evolution and indicated a potential role of Dnmts in epigenetic regulation of response to salinity stress.

Identification and characterization of the plasma membrane H+-ATPase genes in Brassica napus and functional analysis of BnHA9 in salt tolerance

As a primary proton pump, plasma membrane (PM) H+-ATPase plays critical roles in regulating plant growth, development, and stress responses. PM H+-ATPases have been well characterized in many plant species. However, no comprehensive study of PM H+-ATPase genes has been performed in Brassica napus (rapeseed). In this study, we identified 32 PM H+-ATPase genes (BnHAs) in the rapeseed genome, and they were distributed on 16 chromosomes. Phylogenetical and gene duplication analyses showed that the BnHA genes were classified into five subfamilies, and the segmental duplication mainly contributed to the expansion of the rapeseed PM H+-ATPase gene family. The conserved domain and subcellular analyses indicated that BnHAs encoded canonical PM H+-ATPase proteins with 14 highly conserved domains and localized on PM. Cis-acting regulatory element and expression pattern analyses indicated that the expression of BnHAs possessed tissue developmental stage specificity. The 25 upstream open reading frames with the canonical initiation codon ATG were predicted in the 5' untranslated regions of 11 BnHA genes and could be used as potential target sites for improving rapeseed traits. Protein interaction analysis showed that BnBRI1.c associated with BnHA2 and BnHA17, indicating that the conserved activity regulation mechanism of BnHAs may be present in rapeseed. BnHA9 overexpression in Arabidopsis enhanced the salt tolerance of the transgenic plants. Thus, our results lay a foundation for further research exploring the biological functions of PM H+-ATPases in rapeseed.

Genome-wide analysis of the U-box E3 ligases gene family in potato (Solanum tuberosum L.) and overexpress StPUB25 enhance drought tolerance in transgenic Arabidopsis

BACKGROUND

Plant U-box (PUB) E3 ubiquitin ligases have vital effects on various biological processes. Therefore, a comprehensive and systematic identification of the members of the U-box gene family in potato will help to understand the evolution and function of U-box E3 ubiquitin ligases in plants.

RESULTS

This work identified altogether 74 PUBs in the potato (StPUBs) and examined their gene structures, chromosomal distributions, and conserved motifs. There were seventy-four StPUB genes on ten chromosomes with diverse densities. As revealed by phylogenetic analysis on PUBs within potato, Arabidopsis, tomato (Solanum lycopersicum), cabbage (Brassica oleracea), rice (Oryza sativa), and corn (Zea mays), were clustered into eight subclasses (C1-C8). According to synteny analysis, there were 40 orthologous StPUB genes to Arabidopsis, 58 to tomato, 28 to cabbage, 7 to rice, and 8 to corn. In addition, RNA-seq data downloaded from PGSC were utilized to reveal StPUBs' abiotic stress responses and tissue-specific expression in the doubled-monoploid potato (DM). Inaddition, we performed RNA-seq on the 'Atlantic' (drought-sensitive cultivar, DS) and the 'Qingshu NO.9' (drought-tolerant cultivar, DT) in early flowering, full-blooming, along with flower-falling stages to detect genes that might be involved in response to drought stress. Finally, quantitative real-time PCR (qPCR) was carried out to analyze three candidate genes for their expression levels within 100 mM NaCl- and 10% PEG 6000 (w/v)-treated potato plantlets for a 24-h period. Furthermore, we analyzed the drought tolerance of StPUB25 transgenic plants and found that overexpression of StPUB25 significantly increased peroxidase (POD) activity, reduced ROS (reactive oxygen species) and MDA (malondialdehyde) accumulation compared with wild-type (WT) plants, and enhancing drought tolerance of the transgenic plants.

CONCLUSION

In this study, three candidate genes related to drought tolerance in potato were excavated, and the function of StPUB25 under drought stress was verified. These results should provide valuable information to understand the potato StPUB gene family and investigate the molecular mechanisms of StPUBs regulating potato drought tolerance.

Characteristics of conserved microRNAome and their evolutionary adaptation to regulation of immune defense functions in the spleen of silver carp and bighead carp

Immune defense functions of silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis) have shown obvious evolutionary divergence. MiRNAs participate in the fine regulation of immune function. However, the evolutionary adaptation of miRNAs in the regulation of immune defense function is still poorly understood in silver carp and bighead carp. Here, small RNA libraries were constructed from the spleen tissue of one-year-old and three-year-old healthy silver carp and bighead carp, 424 and 422 known conserved miRNAs were respectively identified from the spleen of silver carp and bighead carp by bioinformatic analysis, which 398 were shared between the two species. These conserved miRNAs showed highly similar expression patterns between silver carp and bighead carp, but the abundance in spleen varied greatly in different species. Family analysis showed that miRNA families including mir-8, mir-7, mir-23, mir-338, mir-30, mir-27, mir-221, mir-19, mir-181, mir-17, mir-15, mir-148, mir-130, mir-10 and let-7 were the main miRNAs in the spleen of silver carp and bighead carp. 27 and 51 significant differentially expressed (SDE) miRNAs were identified from silver carp and bighead carp, respectively. Evolution analysis for the predicted target genes of SDE-miRNAs showed that ten biological processes such as blood coagulation, cell adhesion mediated by integrin and adaptive immune response were positively selected. In addition, immune genes including TLR3, NFATC3, MALT1, B2M, GILT and MHCII were positively selected only in silver carp, and they were specifically targeted by the SDE-miRNAs including miR-9-5p, miR-196a-5p, miR-375, miR-122, miR-722, miR-132-3p, miR-727-5p, miR-724, miR-19d-5p and miR-138-5p, respectively. PLA2G4 in Fc epsilon RI signaling pathway was positively selected only in bighead carp and was specifically targeted by the SDE-miRNAs including miR-222b, miR-22b-5p, miR-15c, miR-146a, miR-125c-3p, miR-221-5p, miR-2188-5p, miR-142a-3p, miR-212, miR-138-5p and miR-15b-5p. In particular, SDE-miRNAs such as miR-144-3p, miR-2188-3p, miR-731, miR-363-3p and miR-218b could simultaneously target multiple evolutionarily differentiated immune-related genes. These results indicated that in the spleen of silver carp and bighead carp, conserved miRNAs have obvious evolutionary adaptations in the regulation of immune defense function. The results of this study can provide valuable resources for further revealing themechanism of miRNA in the formation of resistance traits evolution between silver carp and bighead carp.

Genome-wide identification and expression analysis of growth-regulating factors in Dendrobium officinale and Dendrobium chrysotoxum

Background

Dendrobium, one of the largest genera in Orchidaceae, is popular not only for its aesthetic appeal but for its significant medicinal value. Growth-regulating factors (GRFs) play an essential role in plant growth and development. However, there is still a lack of information about the evolution and biological function analysis of the GRF gene family among Dendrobiumspecies.

Methods

Growth-regulating factors from Dendrobium officinale Kimura et Migo and Dendrobium chrysotoxum Lindl. were identified by HMMER and BLAST. Detailed bioinformatics analysis was conducted to explore the evolution and function of GRF gene family in D. officinale and D. chrysotoxum using genomic data, transcriptome data and qRT-PCR technology.

Results

Here, we evaluated the evolution of the GRF gene family based on the genome sequences of D. officinale and D. chrysotoxum. Inferred from phylogenetic trees, the GRF genes were classified into two clades, and each clade contains three subclades. Sequence comparison analysis revealed relatively conserved gene structures and motifs among members of the same subfamily, indicating a conserved evolution of GRF genes within Dendrobiumspecies. However, considering the distribution of orthologous DoGRFs and DcGRFs, and the differences in the number of GRFs among species, we suggest that the GRF gene family has undergone different evolutionary processes. A total of 361 cis-elements were detected, with 33, 141, and 187 related to plant growth and development, stress, and hormones, respectively. The tissue-specific expression of GRFs showed that DoGRF8 may have a significant function in the stem elongation of D. officinale. Moreover, four genes were up-regulated under Methyl-jasmonic acid/methyl jasmonate (MeJA) treatment, showing that DoGRFs and DcGRFs play a crucial role in stress response. These findings provide valuable information for further investigations into the evolution and function of GRF genes in D. officinale and D. chrysotoxum.

Genome-wide identification and characterization of ABC transporter superfamily in the legume Cajanus cajan

Plant ATP-binding cassette (ABC) protein family is the largest multifunctional highly conserved protein superfamily that transports diverse substrates across biological membranes by the hydrolysis of ATP and is also the part of the several other biological processes like cellular detoxification, growth and development, stress biology, and signaling processes. In the agriculturally important legume crop Cajanus cajan, a genome-wide identification and characterization of the ABC gene family was carried out. A total of 159 ABC genes were identified that belong to eight canonical classes CcABCA to CcABCG and CcABCI based on the phylogenetic analysis. The number of genes was highest in CcABCG followed by CcABCC and CcABCB class. A total of 85 CcABC genes were found on 11 chromosomes and 74 were found on scaffold. Tandem duplication was the major driver of CcABC gene family expansion. The dN/dS ratio revealed the purifying selection. The phylogenetic analysis revealed class-specific eight superclades which reflect their functional importance. The largest clade was found to be CcABCG which reflects their functional significance. CcABC proteins were mainly basic in nature and found to be localized in the plasma membrane. The secondary structure prediction revealed the dominance of α-helix. The canonical transmembrane and nucleotide binding domain, signature motif LSSGQ, Walker A, Walker B region, and Q loop were also identified. A class-specific exon-intron pattern was also observed. In addition to core elements, different cis-acting regulatory elements like stress, hormone, and cellular responsive were also identified. Expression profiling of CcABC genes at various developmental stages of different anatomical tissues was performed and it was noticed that CcABCF3, CcABCF4, CcABCF5, CcABCG66, and CcABCI3 had the highest expression. The results of the current study endow us with the further functional analysis of Cajanus ABC in the future.

Overexpression of ABCB transporter genes confer multiple insecticide tolerances in Bactrocera dorsalis (Hendel) (Diptera: Tephritidae)

Bactrocera dorsalis is a notable invasive pest that has developed resistance to several commonly used insecticides in the field, such as avermectin, beta-cypermethrin and malathion. Investigating the mechanisms of insecticide resistance in this pest is of paramount importance for ensuring its effective control. The ATP-binding cassette transporter subfamily B (ABCB) genes, responsible for encoding transmembrane efflux transporters, represent a potential source of insecticide detoxification activity or transportation that remains largely unexplored in B. dorsalis. In this study, seven BdABCB genes were identified and comprehensive analyzed based on the latest genome and transcriptome dataset. Subsequently, we characterized the expression profiles of these genes across different development stages and tissues, as well as under different insecticide exposures. The results showed that the BdABCB genes were expressed at all stages in B. dorsalis, with BdABCB2 and BdABCB7 being highly expressed in the pupal stage, while BdABCB5 and BdABCB6 were highly expressed in the larval stage. Besides, the BdABCBs were highly expressed in the detoxification metabolic tissues. Among them, BdABCB5 and BdABCB6 were significantly overexpressed in the midgut and Malpighian tubules, respectively. Furthermore, with the exception of BdABCB6, the expression levels of the other six BdABCBs were significantly up-regulated following induction with avermectin, beta-cypermethrin and malathion. Six BdABCBs (BdABCB1-5 and BdABCB7) were knocked down by RNA interference, and the interference efficiencies were 46.58%, 39.50%, 45.60%, 33.74%, 66.37% and 63.83%, respectively. After injecting dsBdABCBs, the mortality of flies increased by 25.23% to 39.67% compared to the control upon exposure to the three insecticides. These results suggested that BdABCBs play crucial roles in the detoxification or tolerance of B. dorsalis to multiple insecticides.

Multi-omics analysis of expression profile and prognostic values of connexin family in LUAD

PURPOSE

Our study first explored the expression differences and prognostic significance of Cx genes in pan-cancer and then focused on LUAD. Our objectives were to conducted a comprehensive analysis of the expression profile, prognostic significance, genetic alterations, potential biological functions and drug sensitivity of the Connexin gene family in LUAD.

METHODS

We developed a comprehensive prognostic model for LUAD by combining risk scores with clinical features and created a nomogram to predict 1-, 3-, and 5-year overall survival. Using single-cell sequencing, we examined the expression and biological functions of the identified prognostic markers.

RESULTS

Our risk model revealed that GJB2-5 play a critical role in the prognosis of LUAD patients, associated with many biological processes such as cell cycle, DNA damage, EMT, hypoxia, invasion, and metastasis. Furthermore, the connexin gene family is linked to transcriptional mechanisms such as the extracellular matrix (ECM), migration, mobility, angiogenesis, and the epithelial-mesenchymal transition (EMT) genetic program.

CONCLUSION

The risk model can be used as a potential prognostic factor for LUAD patients and may provide new insights into cancer treatment from perspective of the expression of Cx genes.

Multiple roles of wheat ferritin genes during stress treatment and TaFER5D-1 as a positive regulator in response to drought and salt tolerance

Ferritin not only regulates the plant's iron content but also plays a significant role in the plant's development and resistance to oxidative damage. However, the role of the FER family in wheat has not been systematically elucidated. In this study, 39 FERs identified from wheat and its ancestral species were clustered into two subgroups, and gene members from the same group contain relatively conservative protein models. The structural analyses indicated that the gene members from the same group contained relatively conserved protein models. The cis-acting elements and expression patterns analysis suggested that TaFERs might play an important role combating to abiotic and biotic stresses. In the transcriptional analysis, the TaFER5D-1 gene was found to be significantly up-regulated under drought and salt stresses and was, therefore, selected to further explore the biological functions Moreover, the GFP expression assay revealed the subcellular localization of TaFER5D-1 proteins in the chloroplast, nucleus, membrane and cytoplasm. Over-expression of TaFER5D-1 in transgenic Arabidopsis lines conferred greater tolerance to drought and salt stress. According to the qRT-PCR data, TaFER5D-1 gene over-expression increased the expression of genes related to root development (Atsweet-17 and AtRSL4), iron storage (AtVIT1 and AtYSL1), and stress response (AtGolS1 and AtCOR47). So it is speculated that TaFER5D-1 could improve stress tolerance by promoting root growth, iron storage, and stress-response ability. Thus, the current study provides insight into the role of TaFER genes in wheat.

Wheat gibberellin oxidase genes and their functions in regulating tillering

Multiple genetic factors control tillering, a key agronomy trait for wheat (Triticum aestivum L.) yield. Previously, we reported a dwarf-monoculm mutant (dmc) derived from wheat cultivar Guomai 301, and found that the contents of gibberellic acid 3 (GA3) in the tiller primordia of dmc were significantly higher. Transcriptome analysis indicated that some wheat gibberellin oxidase (TaGAox) genes TaGA20ox-A2, TaGA20ox-B2, TaGA3ox-A2, TaGA20ox-A4, TaGA2ox-A10 and TaGA2ox-B10 were differentially expressed in dmc. Therefore, this study systematically analyzed the roles of gibberellin oxidase genes during wheat tillering. A total of 63 TaGAox genes were identified by whole genome analysis. The TaGAoxs were clustered to four subfamilies, GA20oxs, GA2oxs, GA3oxs and GA7oxs, including seven subgroups based on their protein structures. The promoter regions of TaGAox genes contain a large number of cis-acting elements closely related to hormone, plant growth and development, light, and abiotic stress responses. Segmental duplication events played a major role in TaGAoxs expansion. Compared to Arabidopsis, the gene collinearity degrees of the GAoxs were significantly higher among wheat, rice and maize. TaGAox genes showed tissue-specific expression patterns. The expressions of TaGAox genes (TaGA20ox-B2, TaGA7ox-A1, TaGA2ox10 and TaGA3ox-A2) were significantly affected by exogenous GA3 applications, which also significantly promoted tillering of Guomai 301, but didn't promote dmc. TaGA7ox-A1 overexpression transgenic wheat lines were obtained by Agrobacterium mediated transformation. Genomic PCR and first-generation sequencing demonstrated that the gene was integrated into the wheat genome. Association analysis of TaGA7ox-A1 expression level and tiller number per plant demonstrated that the tillering capacities of some TaGA7ox-A1 transgenic lines were increased. These data demonstrated that some TaGAoxs as well as GA signaling were involved in regulating wheat tillering, but the GA signaling pathway was disturbed in dmc. This study provided valuable clues for functional characterization of GAox genes in wheat.

Genome-wide characterization of SINA E3 ubiquitin ligase family members and their expression profiles in response to various abiotic stresses and hormones in kiwifruit

SINA (Seven in absentia) proteins in the subtype of E3 ubiquitin ligase family have important functions in regulating the growth and development as well as in response to abiotic and biotic stresses in plants. However, the characteristics and possible functions of SINA family proteins in kiwifruit are not studied. In this research, a total number of 11 AcSINA genes in the kiwifruit genome were identified. Chromosome location and multiple sequence alignment analyses indicated that they were unevenly distributed on 10 chromosomes and all contained the typical N-terminal RING domain and C-terminal SINA domain. Phylogenetic, gene structure and collinear relationship analyses revealed that they were highly conserved with the same gene structure, and have gone through segmental duplication events. Expression pattern analyses demonstrated that all AcSINAs were ubiquitously expressed in roots, stems and leaves, and were responsive to different abiotic and plant hormone treatments with overlapped but distinct expression patterns. Further yeast two-hybrid and Arabidopsis transformation analyses demonstrated most AcSINAs interacted with itself or other AcSINA members to form homo- or heterodimers, and ectopic expression of AcSINA2 in Arabidopsis led to hypersensitive growth phenotype of transgenic seedlings to ABA treatment. Our results reveal that AcSINAs take part in the response to various abiotic stresses and hormones, and provide important information for the functional elucidation of AcSINAs in vine fruit plants.

The G2-Like gene family in Populus trichocarpa: identification, evolution and expression profiles

The Golden2-like (GLK) transcription factors are plant-specific transcription factors (TFs) that perform extensive and significant roles in regulating chloroplast development. Here, genome-wide identification, classification, conserved motifs, cis-elements, chromosomal locations, evolution and expression patterns of the PtGLK genes in the woody model plant Populus trichocarpa were analyzed in detail. In total, 55 putative PtGLKs (PtGLK1-PtGLK55) were identified and divided into 11 distinct subfamilies according to the gene structure, motif composition and phylogenetic analysis. Synteny analysis showed that 22 orthologous pairs and highly conservation between regions of GLK genes across P. trichocarpa and Arabidopsis were identified. Furthermore, analysis of the duplication events and divergence times provided insight into the evolutionary patterns of GLK genes. The previously published transcriptome data indicated that PtGLK genes exhibited distinct expression patterns in various tissues and different stages. Additionally, several PtGLKs were significantly upregulated under the responses of cold stress, osmotic stress, and methyl jasmonate (MeJA) and gibberellic acid (GA) treatments, implying that they might take part in abiotic stress and phytohormone responses. Overall, our results provide comprehensive information on the PtGLK gene family and elucidate the potential functional characterization of PtGLK genes in P. trichocarpa.

Identification, expression profiles and involvement in insecticides tolerance and detoxification of carboxylesterase genes in Bactrocera dorsalis

Carboxylesterases (CarEs) are a multifunctional superfamily of enzymes and play an important role in detoxification of various insecticides in insects. The oriental fruit fly, Bactrocera dorsalis, is one of the most destructive agricultural pests and has developed different degrees of resistance to organophosphates in field. However, the involvement of BdCarEs in tolerance or resistance to other alternative insecticides are still unclear. In the present study, 33 BdCarEs genes were identified based on the genome database of B. dorsalis. Phylogenetic analysis demonstrated that they were classified into nine clades, with abundance of α-esterases. Meanwhile, the sequence characterization and the chromosome distribution were also analyzed. The spatiotemporal expression analysis of BdCarEs genes suggested that the diversity of potential function in different physiological processes. With the exception of BdCarE21, all BdCarEs genes responded to at least one insecticide exposure, and BdCarE20 was found to be up-regulated after exposure to all five tested insecticides individually. Eight BdCarEs genes were overexpressed in MR strain when compared to that in SS strain. Subsequently, knockdown the expression of representative BdCarEs genes significantly increased the susceptibility of the oriental fruit fly to corresponding insecticides, which indicated that the tested BdCarEs genes contributed to one or multiple insecticide detoxification. These findings provide valuable insights into the potential role in respond to tolerance or resistance to insecticides with different mode of action, and will facilitate development of efficiency management strategy for B. dorsalis.

Identification of MYB gene family and functional analysis of GhMYB4 in cotton (Gossypium spp.)

Myeloblastosis (MYB) transcription factors (TFs) form a large gene family involved in a variety of biological processes in plants. Little is known about their roles in the development of cotton pigment glands. In this study, 646 MYB members were identified in Gossypium hirsutum genome and phylogenetic classification was analyzed. Evolution analysis revealed assymetric evolution of GhMYBs during polyploidization and sequence divergence of MYBs in G. hirustum was preferentially happend in D sub-genome. WGCNA (weighted gene co-expression network analysis) showed that four modules had potential relationship with gland development or gossypol biosynthesis in cotton. Eight differentially expressed GhMYB genes were identified by screening transcriptome data of three pairs of glanded and glandless cotton lines. Of these, four were selected as candidate genes for cotton pigment gland formation or gossypol biosynthesis by qRT-PCR assay. Silencing of GH_A11G1361 (GhMYB4) downregulated expression of multiple genes in gossypol biosynthesis pathway, indicating it could be involved in gossypol biosynthesis. The potential protein interaction network suggests that several MYBs may have indirect interaction with GhMYC2-like, a key regulator of pigment gland formation. Our study was the systematic analysis of MYB genes in cotton pigment gland development, providing candidate genes for further study on the roles of cotton MYB genes in pigment gland formation, gossypol biosynthesis and future crop plant improvement.

Small Auxin Up RNA (SAUR) gene family identification and functional genes exploration during the floral organ and fruit developmental stages in pineapple (Ananas comosus L.) and its response to salinity and drought stresses

In plants, sexual reproduction relies on the proper development of floral organs that facilitate the successful development of fruits and seeds. Auxin responsive small auxin-up RNA (SAUR) genes play essential roles in floral organ formation and fruit development. However, little is known about the role of SAUR genes in pineapple floral organ formation and fruit development as well as stress responses. In this study, based on genome information and transcriptome datasets, 52 AcoSAUR genes were identified and grouped into 12 groups. The gene structure analysis revealed that most AcoSAUR genes did not have introns, although auxin-acting elements were abundant in the promoter region of AcoSAUR members. The expression analysis across the multiple flower and fruit development stages revealed differential expression of AcoSAUR genes, indicating a tissue and stage-specific function of AcoSAURs. Correlation analysis and pairwise comparisons between gene expression and tissue specificity identified stamen-, petal-, ovule-, and fruit-specific AcoSAURs involved in pineapple floral organs (AcoSAUR4/5/15/17/19) and fruit development (AcoSAUR6/11/36/50). RT-qPCR analysis revealed that AcoSAUR12/24/50 played positive roles in response to the salinity and drought treatment. This work provides an abundant genomic resource for functional analysis of AcoSAUR genes during the pineapple floral organs and fruit development stages. It also highlights the role of auxin signaling involved in pineapple reproductive organ growth.

Feature selection combined with top-down and bottom-up strategies for survival analysis: A case of prognostic prediction in glioblastoma

Over the last decades, molecular signatures have attracted extensive attention in cancer research. However, most of the reported biomarkers show a weak distinguishing ability in predicting the survival risks of patients. Actually, univariate analysis is generally considered in regression analysis, which makes the existing statistical methods ineffective. Furthermore, there is too much human involvement in the ways of classifying patients with high and low risk. Last but not least, the participation of therapy after conservative surgery also makes the survival analysis more complex. In order to solve these problems, we propose a solid method of feature selection which combines top-down and bottom-up strategies. The top-down strategy is to randomly extract some genes each time and select candidate genes through cumulative voting. The bottom-up strategy is to fully enumerate the selected genes and to use a clustering algorithm to classify samples. We analyzed glioblastoma data from the Cancer Genome Atlas (TCGA) and got candidate signatures. The results of simulation data, as well as an independent test set the Chinese Glioma Genome Atlas (CGGA), verified the reliability of the method and validity of the selected features.

Comparative genomic analysis of the CPK gene family in Moso bamboo (Phyllostachys edulis) and the functions of PheCPK1 in drought stress

Calcium-dependent protein kinases (CPKs) play an important role in plant regulation of growth and development, and in the responses to biotic and abiotic stresses. In the present study, we analyzed Moso bamboo (Phyllostachys edulis) CPK genes and their closely related five gene families (Brachypodium distachyon, Hordeum vulgare L., Oryza sativa, Setaria italica, and Zea mays) comprehensively, including phylogenetic relationships, gene structures, and synteny analysis. Thirty Moso bamboo CPKs were divided into four subgroups; in each subgroup, the constituent parts of gene structure were relatively conserved. Furthermore, analysis of expression profiles showed that most PheCPK genes are significantly upregulated under drought and cold stress, especially PheCPK1. Overexpression of PheCPK1 in Arabidopsis reduced plant tolerance to drought stress, as determined through physiological analyses of the relative water content, relative electrical leakage, and malondialdehyde content. It also activated the expressions of stress-related genes. In addition, overexpression of PheCPK1 in Arabidopsis exhibited significantly decreased reactive oxygen species (ROS)-scavenging ability. Taken together, these results suggest that PheCPK1 may act as a negative regulator involved in the drought stress responses.

Identification and analysis of differentially expressed trihelix genes in maize (Zea mays) under abiotic stresses

Background

Trihelix transcription factors play important roles in triggering plant growth and imparting tolerance against biotic and abiotic stresses. However, a systematical analysis of the trihelix transcription factor family under heat and drought stresses in maize has not been reported.

Methods

PlantTFDB and TBtools were employed to identify the trihelix domain-containing genes in the maize genome. The heat-regulated transcriptome data for maize were obtained from NCBI to screen differentially expressed ZmTHs genes through statistical analysis. The basic protein sequences, chromosomal localization, and subcellular localization were analyzed using Maize GDB, Expasy, SOMPA, TBtools, and Plant-mPLoc. The conserved motifs, evolutionary relationships, and cis-elements, were analyzed by MEME, MEGA7.0 and PlantCARE software, respectively. The tissue expression patterns of ZmTHs and their expression profiles under heat and drought stress were detected using quantitative real-time PCR (qRT-PCR).

Results

A total of 44 trihelix family members were discovered, and members were distributed over 10 chromosomes in the maize genome. A total of 11 genes were identified that were regulated by heat stress; these were unevenly distributed on chromosomes 1, 2, 4, 5, and 10. ZmTHs encoded a total of 16 proteins, all of which were located in the nucleus; however, ZmTH04.1 was also distributed in the chloroplast. The protein length varied from 206 to 725 amino acids; the molecular weight ranged from 22.63 to 76.40 kD; and the theoretical isoelectric point (pI) ranged from 5.24 to 11.2. The protein's secondary structures were mainly found to be random coils and α-helices, with fewer instances of elongation chains and β-rotations. Phylogenetic relationship analysis showed that these can be divided into five sub-groups. The conserved domain of ZmTHs was GT1 or MyB_DNA-Bind_4. The protein and gene structure of ZmTHs differed greatly among the subfamilies, while the structures within the subfamilies were similar. The promoter of ZmTHs contained abundant tissue-specific expression cis-acting elements and abiotic stress response elements. qRT-PCR analysis showed that ZmTHs expression levels were significantly different in different tissues. Furthermore, the expression of ZmTH08 was dramatically up-regulated by heat stress, while the expression of ZmTH03, ZmTH04, ZmTH05, ZmTH06, ZmTH07, ZmTH09, ZmTH10, and ZmTH11 were down-regulated by heat stress. Upon PEG-simulated drought stress, ZmTH06 was significantly up-regulated, while ZmTH01 and ZmTH07 were down-regulated.

Conclusions

We performed a genome-wide, systematic identification and analysis of differentially expressed trihelix genes under heat and drought stresses in maize.

Genome-wide identification of MADS-box gene family in orchardgrass and the positive role of DgMADS114 and DgMADS115 under different abiotic stress

Abiotic stress, a major factor limit growth and productivity of major crops. Orchardgrass is one of the most important cool-season forage grasses in the world, and it is highly tolerant to abiotic stress. The MADS-box transcription factor family is one of the largest families in plants, and it plays vital roles in multiple biological processes. However, MADS-box transcription factors in orchardgrass, especially those involved in abiotic stress, have not yet been elucidated. Here, 123 DgMADS-box members were identified in orchardgrass and a detailed overview has been presented. Syntenic analysis indicated that the expansion of the DgMADS-box genes in orchardgrass is mainly dependent on tandem duplication events. Some DgMADS-box genes were induced by multiple abiotic stresses, indicating that these genes may play critical regulatory roles in orchardgrass response to various abiotic stresses. Heterologous expression showed that DgMADS114 and DgMADS115 could enhance stress tolerance of transgenic Arabidopsis, as revealed by longer root length or higher survival rates under PEG, NaCl, ABA, and heat stress. The results of this study provide a scientific basis for clarifying the functional characterization of MADS-box genes in orchardgrass in response to environmental stress can be further used to improve forages and crops via breeding programs.

A systematical genome-wide analysis and screening of WRKY transcription factor family engaged in abiotic stress response in sweetpotato

BACKGROUND

WRKY transcription factors play pivotal roles in regulating plant multiple abiotic stress tolerance, however, a genome-wide systematical analysis of WRKY genes in sweetpotato is still missing.

RESULTS

Herein, 84 putative IbWRKYs with WRKY element sequence variants were identified in sweetpotato reference genomes. Fragment duplications, rather than tandem duplications, were shown to play prominent roles in IbWRKY gene expansion. The collinearity analysis between IbWRKYs and the related orthologs from other plants further depicted evolutionary insights into IbWRKYs. Phylogenetic relationships displayed that IbWRKYs were divided into three main groups (I, II and III), with the support of the characteristics of exon-intron structures and conserved protein motifs. The IbWRKY genes, mainly from the group Ib, displayed remarkable and diverse expression profiles under multiple abiotic stress (NaCl, PEG6000, cold and heat) and hormone (ABA, ACC, JA and SA) treatments, which were determined by RNA-seq and qRT-PCR assays, suggesting their potential roles in mediating particular stress responses. Moreover, IbWRKY58L could interact with IbWRKY82 as revealed by yeast two-hybrid based on the protein interaction network screening. And abiotic stress-remarkably induced IbWRKY21L and IbWRKY51 were shown to be localized in the nucleus and had no transactivation activities.

CONCLUSION

These results provide valuable insights into sweetpotato IbWRKYs and will lay a foundation for further exploring functions and possible regulatory mechanisms of IbWRKYs in abiotic stress tolerance.

Characteristics of cathepsin members and expression responses to poly I:C challenge in Pacific cod (Gadus macrocephalus)

Cathepsins are major lysosomal enzymes that participate in necessary physiological processes, including protein degradation, tissue differentiation, and innate or adaptive immune responses. According to their proteolytic activity, vertebrate cathepsins are classified as cysteine proteases (cathepsins B, C, F, H, K, L, O, S, V, W, and X or Z), aspartic proteases (cathepsin D and E), and serine proteases (cathepsin A and G). Several cathepsins were reported in teleosts, however, no cathepsin gene has been identified from Pacific cod so far. In the present study, a total of 13 cathepsin genes were identified for Pacific cod. The evolutionary path of each cathepsin gene was demonstrated via analysis of phylogenetic trees, multiple alignments, conserved domains, motif compositions, and tertiary structures. Tissue distribution analysis showed that all cathepsin genes were ubiquitously expressed in eight healthy tissues but they exhibited diverse levels of expression. Several cathepsin genes were found to be highly expressed in the kidney, spleen, head kidney and liver, whereas low or modest levels were detected in the gills, skin, intestines, and heart. Temporal-specific expression of cathepsins in early developmental stages of Pacific cod were also conducted. CTSK, S, F, and Z were highly expressed at 1 dph and 5 dph and decreased later, while CTSL, L1, and L.1 transcript levels gradually increased in a time-dependent manner. Additionally, the expression profiles of cathepsin genes in Pacific cod were evaluated in the spleen and liver after poly I:C challenge. The results indicated that all cathepsin genes were significantly upregulated upon poly I:C stimulation, suggesting that they play key roles in antiviral immune responses in Pacific cod. Our findings establish a foundation for future exploration of the molecular mechanisms of cathepsins in modulating antiviral immunity in Pacific cod.

Comprehensive analysis of lncRNA expression profiles in postmenopausal osteoporosis

To explore the key lncRNAs affecting postmenopausal osteoporosis (PMOP) progression, the transcriptome sequencing of peripheral blood mononuclear cells from fifteen early postmenopausal women, according to bone mineral density, were divided into groups of osteoporosis, osteopenia and normality, in each of which the expression profiles of lncRNAs was investigated. From the results we observed nine candidates of lncRNAs, which were to be compared with miRBase, and found that MIR22HG as one candidate of lncRNA was most likely to be directly used as miRNA precursor. Based on the KEGG annotation and lncRNA-miRNA-mRNA-KEGG network, we analyzed the potential role of candidate lncRNAs. The results showed that the expression profiles of lncRNAs could help identify the novel ones involved in the progression of PMOP, and that MIR22HG could serve as a miRNA precursor to regulate FoxO signaling pathway in bone metabolism. Our findings can be of great help in predicting and diagnosing early PMOP.

Genome-wide identification and analysis of scavenger receptors and their expression profiling in response to Edwardsiella tarda infection in Japanese flounder (Paralichthys olivaceus)

The scavenger receptors (SRs) gene family, as one of pattern recognition receptors, participates in the innate immune response in diverse lineages. However, the systematic identification, characteristics and functions of SRs family are lacking in teleost. Here, we identified all 19 SRs family members in Japanese flounder (Paralichthys olivaceus) based on the genome and transcriptome data. Phylogenetic and Ka/Ks analysis demonstrated that these SRs genes were divided into five classes and all exhibited pronounced purified selection pressures. Whole genome duplication event was found in colec12, scarb2, and lamp1. Gene structure, functional domain and motif distribution analyses indicated that SRs within the different subfamilies are severely conservative. SRs genes showed diverse expression patterns in the embryogenesis and unchanged tissues. The regulations of 14 SRs genes in blood, gill and kidney after E. tarda infection suggested their roles in innate immune response. Meanwhile, ten SRs genes were differentially expressed after E. tarda stimulation in macrophages in vitro. Then we proved that PoSCARA3 could suppress the activity of NF-κB and AP-1 in HEK 293T cells by dual-luciferase assays. In summary, this study provided valuable basis for further functional characterization and immune functions of SRs genes in P. olivaceus.

Genome wide analysis of DWARF27 genes in soybean and functional characterization of GmD27c reveals eminent role of strigolactones in rhizobia interaction and nodulation in Glycine max

BACKGROUND

Strigolactones (SLs) are newly identified hormones and their biosynthesis is stimulated under phosphate deprivation and accomplished by the action of several enzymes, including the beta-carotene isomerase DWARF27 (D27). Expression of D27 is well renowned to respond to phosphate insufficiency. However, the identification and functional analysis of the carotenoid isomerase D27 genes are not elucidated in soybean.

METHODS AND RESULTS

A total of six D27 genes were identified in the soybean genome and designated on the basis of chromosomal localization. According to the findings, these genes were irregularly distributed on chromosomes, and segmental repetition led to the expansion of the soybean GmD27 gene family. Based on a neighbor-joining phylogenetic tree, the predicted D27 proteins of soybean were divided into three clades. Based on RNA seq data analysis, GmD27 genes were differently expressed in various tissues but GmD27c was the highest. Therefore, GmD27c was chosen for the additional functional study due to its rather obvious transcription in nodulation and roots. RT-qPCR results showed that GmD27c was highly expressed in different nodule stages and in response to rhizobia infection. Functional characterization of GmD27c revealed that overexpression of GmD27c led to higher nodule number, while GmD27c knockdown caused fewer nodules compared to GUS control. Furthermore, GmD27c overexpressed and knockdown lines oppositely regulated the expression of numerous nodulation genes, which are vital for the development of nodules.

CONCLUSION

This study not only discovered that SL biosynthesis and signaling pathway genes are conserved, but it also revealed that SL biosynthesis gene GmD27c and legume rhizobia have close interactions in controlling plant nodule number.

The identification of miRNA and mRNA expression profiles associated with pediatric atypical teratoid/rhabdoid tumor

BACKGROUND

Atypical teratoid/rhabdoid tumor (AT/RT) is a malignant pediatric tumor of the central nervous system (CNS) with high recurrence and low survival rates that is often misdiagnosed. MicroRNAs (miRNAs) are involved in the tumorigenesis of numerous pediatric cancers, but their roles in AT/RT remain unclear.

METHODS

In this study, we used miRNA sequencing and gene expression microarrays from patient tissue to study both the miRNAome and transcriptome traits of AT/RT.

RESULTS

Our findings demonstrate that 5 miRNAs were up-regulated, 16 miRNAs were down-regulated, 179 mRNAs were up-regulated and 402 mRNAs were down-regulated in AT/RT. qPCR revealed that hsa-miR-17-5p and MAP7 mRNA were the most significantly differentially expressed miRNA and mRNA in AT/RT tissues. Furthermore, the results from analyses using the miRTarBase database identified MAP7 mRNA as a target gene of hsa-miR-17-5p.

CONCLUSIONS

Our findings suggest that the dysregulation of hsa-miR-17-5p may be a pivotal event in AT/RT and miRNAs that may represent potential therapeutic targets and diagnostic biomarkers.

Genome-wide identification, expression analysis and evolutionary relationships of the IQ67-domain gene family in common wheat (Triticum aestivum L.) and its progenitors

BACKGROUND

The plant-specific IQ67-domain (IQD) gene family plays an important role in plant development and stress responses. However, little is known about the IQD family in common wheat (Triticum aestivum L), an agriculturally important crop that provides more than 20% of the calories and protein consumed in the modern human diet.

RESULTS

We identified 125 IQDs in the wheat genome and divided them into four subgroups by phylogenetic analysis. The IQDs belonging to the same subgroup had similar exon-intron structure and conserved motif composition. Polyploidization contributed significantly to the expansion of IQD genes in wheat. Characterization of the expression profile of these genes revealed that a few T. aestivum (Ta)IQDs showed high tissue-specificity. The stress-induced expression pattern also revealed a potential role of TaIQDs in environmental adaptation, as TaIQD-2A-2, TaIQD-3A-9 and TaIQD-1A-7 were significantly induced by cold, drought and heat stresses, and could be candidates for future functional characterization. In addition, IQD genes in the A, B and D subgenomes displayed an asymmetric evolutionary pattern, as evidenced by their different gain or loss of member genes, expression levels and nucleotide diversity.

CONCLUSIONS

This study elucidated the potential biological functions and evolutionary relationships of the IQD gene family in wheat and revealed the divergent fates of IQD genes during polyploidization.

Genome-wide identification, evolutionary and expression analyses of LEA gene family in peanut (Arachis hypogaea L.)

BACKGROUND

Late embryogenesis abundant (LEA) proteins are a group of highly hydrophilic glycine-rich proteins, which accumulate in the late stage of seed maturation and are associated with many abiotic stresses. However, few peanut LEA genes had been reported, and the research on the number, location, structure, molecular phylogeny and expression of AhLEAs was very limited.

RESULTS

In this study, 126 LEA genes were identified in the peanut genome through genome-wide analysis and were further divided into eight groups. Sequence analysis showed that most of the AhLEAs (85.7%) had no or only one intron. LEA genes were randomly distributed on 20 chromosomes. Compared with tandem duplication, segmental duplication played a more critical role in AhLEAs amplication, and 93 segmental duplication AhLEAs and 5 pairs of tandem duplication genes were identified. Synteny analysis showed that some AhLEAs genes come from a common ancestor, and genome rearrangement and translocation occurred among these genomes. Almost all promoters of LEAs contain ABRE, MYB recognition sites, MYC recognition sites, and ERE cis-acting elements, suggesting that the LEA genes were involved in stress response. Gene transcription analyses revealed that most of the LEAs were expressed in the late stages of peanut embryonic development. LEA3 (AH16G06810.1, AH06G03960.1), and Dehydrin (AH07G18700.1, AH17G19710.1) were highly expressed in roots, stems, leaves and flowers. Moreover, 100 AhLEAs were involved in response to drought, low-temperature, or Al stresses. Some LEAs that were regulated by different abiotic stresses were also regulated by hormones including ABA, brassinolide, ethylene and salicylic acid. Interestingly, AhLEAs that were up-regulated by ethylene and salicylic acid showed obvious subfamily preferences. Furthermore, three AhLEA genes, AhLEA1, AhLEA3-1, and AhLEA3-3, which were up-regulated by drought, low-temperature, or Al stresses was proved to enhance cold and Al tolerance in yeast, and AhLEA3-1 enhanced the drought tolerance in yeast.

CONCLUSIONS

AhLEAs are involved in abiotic stress response, and segmental duplication plays an important role in the evolution and amplification of AhLEAs. The genome-wide identification, classification, evolutionary and transcription analyses of the AhLEA gene family provide a foundation for further exploring the LEA genes' function in response to abiotic stress in peanuts.

Genome-wide characterization and expression analysis of Erf gene family in cotton

BACKGROUND

AP2/ERF transcription factors are important in a variety of biological activities, including plant growth, development, and responses to biotic and abiotic stressors. However, little study has been done on cotton's AP2/ERF genes, although cotton is an essential fibre crop. We were able to examine the tissue and expression patterns of AP2/ERF genes in cotton on a genome-wide basis because of the recently published whole genome sequence of cotton. Genome-wide analysis of ERF gene family within two diploid species (G. arboreum & G. raimondii) and two tetraploid species (G. barbadense, G. hirsutum) was performed.

RESULTS

A total of 118, 120, 213, 220 genes containing the sequence of single AP2 domain were identified in G. arboreum, G. raimondii, G. barbadense and G. hirsutum respectively. The identified genes were unevenly distributed across 13/26 chromosomes of A and D genomes of cotton. Synteny and collinearity analysis revealed that segmental duplications may have played crucial roles in the expansion of the cotton ERF gene family, as well as tandem duplications played a minor role. Cis-acting elements of the promoter sites of Ghi-ERFs genes predict the involvement in multiple hormone responses and abiotic stresses. Transcriptome and qRT-PCR analysis revealed that Ghi-ERF-2D.6, Ghi-ERF-12D.13, Ghi-ERF-6D.1, Ghi-ERF-7A.6 and Ghi-ERF-11D.5 are candidate genes against salinity tolerance in upland cotton.

CONCLUSION

Overwhelmingly, the present study paves the way to better understand the evolution of cotton ERF genes and lays a foundation for future investigation of ERF genes in improving salinity stress tolerance in cotton.

Genome-wide analysis of trehalose-6-phosphate phosphatases (TPP) gene family in wheat indicates their roles in plant development and stress response

BACKGROUND

Trehalose-6-phosphate phosphatases genes (TPPs) are involved in the development and stress response of plants by regulating the biosynthesis of trehalose, though little is currently known about TPPs in common wheat (Triticum aestivum L.).

RESULTS

In this study, we performed a genome-wide identification of the TPP gene family in common wheat, and identified a total of 31 TaTPP genes. These were subdivided into six subfamilies based on the phylogenetic relationships and the conservation of protein in six monocot and eudicot plants. The majority of TPP genes were represented by 2-3 wheat homoalleles (named TaTPPX_ZA, TaTPPX_ZB, or TaTPPX_ZD), where Z is the location on the wheat chromosome of the gene number (X). We also analyzed the chromosomal location, exon-intron structure, orthologous genes, and protein motifs of the TaTPPs. The RNA-seq data was used to perform an expression analysis, which found 26 TaTPP genes to be differentially expressed based on spatial and temporal characteristics, indicating they have varied functions in the growth and development of wheat. Additionally, we assessed how the promoter regulatory elements were organized and used qRT-PCR in the leaves to observe how they were expressed following ABA, salt, low tempreture, and drought stress treatments. All of these genes exhibited differential expression against one or more stress treatments. Furthermore, ectopic expression of TaTPP11 in Arabidopsis exhibited a phenotype that delayed plant development but did not affect seed morphology.

CONCLUSIONS

TaTPPs could serve important roles in the development and stress response in wheat. These results provide a basis for subsequent research into the function of TaTPPs.

Identification and characterization of the BEL1-like genes reveal their potential roles in plant growth and abiotic stress response in tomato

BEL1-like (BELL) transcription factors, belonging to three-amino acid-loop-extension (TALE) superfamily, are ubiquitous in plants. BELLs regulate a wide range of plant biological processes, but the understanding of the BELL family in tomato (Solanum lycopersicum) remains fragmentary. In this study, a total of 14 members of the SlBELL family were identified in tomato. SlBELL proteins contained the conserved BELL and SKY domains that served as typical structures of the BELL family. Syntenic analysis indicated that the BELL orthologs between tomato and other dicots had close evolutionary relationships. Furthermore, the promoters of SlBELLs contained numerous cis-elements related to plant growth, development, and stress response. The SlBELL genes exhibited different tissue-specific expression profiles and responded to cold, heat, and drought stresses, implying their potential functions in regulating multiple aspects of plant growth, as well as in response to abiotic stresses. Through the interaction network prediction, we found that most SlBELL proteins displayed probable interactions with the KNOTTED1-like (KNOX) proteins, another kind of transcription factor in the TALE superfamily. These findings laid foundations for further dissection of the functions of SlBELL genes in tomato, as well as for exploration of the evolutionary relationships of BELL homologs among different plant species.

Effects of different photoperiods on flower opening, flower closing and circadian expression of clock-related genes in Iris domestica and I. dichotoma

The circadian clock can entrain to forced light-dark cycles by adjusting the phases and periods of flower opening and closing in ephemeral flowers. The responses of circadian rhythms to the same light conditions differ from species. However, the differences in internal genetic mechanisms underlying the different responses between species remain unclear. Iris domestica and I. dichotoma have ephemeral flowers and significantly divergent flower opening and closing times. The effects of different photoperiods (continuous darkness, 4L20D, 8L16D, 12L12D, 16L8D, 20L4D and continuous white light) on flower opening and closing, and expression patterns of seven genes (CRYPTOCHROME 1, PHYTOCHROME B, LATE ELONGATED HYPOCOTYL, PSEUDO RESPONSE REGULATOR 95, PHYTOCHROME INTERACTING FACTOR 4-like, SMUX AUXIN UP RNA 64-like and senescence-associated gene 39-like) involved in the circadian regulation of flower opening and closing were compared between I. domestica and I. dichotoma. Flower opening and closing in the two species exhibited circadian rhythms under continuous darkness (DD), but showed arrhythmia in continuous white light (LL). In the two species, keeping robust rhythms, strong synchronicity, rapid progressions of flower opening and closing and reaching full opening stage required a dark period longer than 4 h. In light-dark cycles with dark periods longer than 4 h, flower opening and closing times of the two species delayed with the delay of dawn, and the degree to which flower opening time varies with the time of dawn was greater in I. dichotoma than in I. domestica. The arrhythmia of flower opening and closing under 20L4D and LL would result from the arrhythmic output signals rather than arrhythmia of oscillators and photoreceptors. The different responses of the two species to the change of photoperiods would be caused by the transcriptional differences of genes in the output pathway of circadian clock system rather than in the input pathway or oscillators.

Genome-wide identification and genetic characterization of the CaMYB family and its response to five types of heavy metal stress in hot pepper (Capsicum annuum cv. CM334)

MYB proteins play a crucial role in plant growth and development and stress responses. In this study, 160 members of the MYB gene family from the pepper genome database were used to analyze gene structures, chromosome localization, collinearity, genetic affinity and expression in response to heavy metals. The results identified R2R3-MYB members and further phylogenetically classified them into 35 subgroups based on highly conserved gene structures and motifs. Collinearity analysis showed that segmental duplication events played a crucial role in the functional expansion of the CaMYB gene family by intraspecific collinearity, and at least 12 pairs of CaMYB genes existed between species prior to the differentiation between monocots and dicots. Moreover, the upstream CaMYB genes were mainly localized to the phytohormone elements ABRE and transcription factor elements MYB and MYC. Further analysis revealed that MYB transcription factors were closely associated with a variety of abiotic stress-related proteins (e.g., MAC-complex and SKIP). Under the stress of five metal ions, Cd²⁺, Cu²⁺, Pb²⁺, Zn²⁺, and Fe³⁺, the expression levels of some CaMYB family genes were upregulated. Of these genes, pairing homologous 1 (PH-1), PH-13, and PH-15 in the roots of Capsicum annuum were upregulated to the greatest extent, indicating that these three MYB family members are particularly sensitive to these five metals. This study provides a theoretical reference for the analysis of the molecular regulatory mechanism of MYB family genes in mediating the response to heavy metals in plants. This study reveals the mode of interaction between MYB and a variety of abiotic stress proteins and clarifies the biological functions of CaMYB family members in the regulation of heavy metal stress.

Gene expression and functional analysis of different heat shock protein (HSPs) in Ruditapes philippinarum under BaP stress

Heat shock proteins (HSPs) are a class of highly conserved proteins which can protect cells against various types of stress. However, little information on the mechanism involved in the organic contaminants stress response of HSPs is available, especially in marine invertebrates. The present study was conducted to evaluate the responses of HSPs in clams (Ruditapes philippinarum) under Benzo[a] pyrene (BaP) exposure. The clams were exposed to BaP (concentrations: 0, 0.1, 1, 10 μg/L) for 15 days. 6 HSPs mRNA were classified, and the results of tissue distribution indicated that 4 HSPs gene expressed most in the digestive glands. The transcription level of 6 HSPs (HSP22-1, HSP22-2, HSP40A, HSP60, HSP70, HSP90) genes and the aryl hydrocarbon receptor signaling pathway-related genes, and detoxification system-related enzymes activities were analyzed at 0, 1, 3, 6, 10 and 15 days. The activities of phase II detoxification metabolic enzymes and signaling pathway related genes in clams were severely affected by BaP stress and presented significant difference. Our result suggested that HSPs were produced in the presence of BaP and participated in the process of detoxification metabolism to a certain extent. Additionally, the transcription of HSP40A gene may be used as a potential biomarker of BaP exposure due to its evident concentration- and time-dependent expression pattern. Overall, the study investigated the classification of HSPs in R. philippinarum, provided information about the expression profiles of various HSPs after BaP exposure and broadened the understanding mechanism of HSPs in detoxification defense system under PAHs stress in mollusks.

In silico identification, characterization expression profile of WUSCHEL-Related Homeobox (WOX) gene family in two species of kiwifruit

The WUSCHEL (WUS)-related homeobox (WOX) gene family is a class of plant-specific transcriptional factors and plays a crucial role in forming the shoot apical meristem and embryonic development, stem cell maintenance, and various other developmental processes. However, systematic identification and characterization of the kiwifruit WOX gene family have not been studied. This study identified 17 and 10 WOX genes in A. chinensis (Ac) and A. eriantha (Ae) genomes, respectively. Phylogenetic analysis classified kiwifruit WOX genes from two species into three clades. Analysis of phylogenetics, synteny patterns, and selection pressure inferred that WOX gene families in Ac and Ae had undergone different evolutionary patterns after whole-genome duplication (WGD) events, causing differences in WOX gene number and distribution. Ten conserved motifs were identified in the kiwifruit WOX genes, and motif architectures of WOXs belonging to different clades highly diverged. The cis-element analysis and expression profiles investigation indicated the functional differentiation of WOX genes and identified the potential WOXs in response to stresses. Our results provided insight into general characters, evolutionary patterns, and functional diversity of kiwifruit WOXs.

Dysregulated lncRNA and mRNA may promote the progression of ischemic stroke via immune and inflammatory pathways: results from RNA sequencing and bioinformatics analysis

BACKGROUND

Long non-coding RNAs (lncRNAs) are widely involved in gene transcription regulation and which act as epigenetic modifiers in many diseases.

OBJECTIVE

To determine whether lncRNAs are involved in ischemic stroke (IS), we analyzed the expression profile of lncRNAs and mRNAs in IS.

METHODS

RNA sequencing was performed on the blood of three pairs of IS patients and healthy controls. Differential expression analysis was used to identify differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs). Based on the co-expression relationships between lncRNA and mRNA, a series of bioinformatics analysis including GO and KEGG enrichment analysis and PPI analysis, were conducted to predict the function of lncRNA.

RESULTS

RNA sequencing produced a total of 5 DElncRNAs and 144 DEmRNAs. Influenza A pathway and Herpes simplex infection pathway were the most significant pathways. EP300 and NFKB1 were the most important target proteins, and Human leucocyte antigen (HLA) family were the key genes in IS.

CONCLUSIONS

Analysis of this study revealed that dysregulated lncRNAs in IS may lead to IS by affecting the immune and inflammation system.

Class I histone deacetylases (HDAC) critically contribute to Ewing sarcoma pathogenesis

Background

Histone acetylation and deacetylation seem processes involved in the pathogenesis of Ewing sarcoma (EwS). Here histone deacetylases (HDAC) class I were investigated.

Methods

Their role was determined using different inhibitors including TSA, Romidepsin, Entinostat and PCI-34051 as well as CRISPR/Cas9 class I HDAC knockouts and HDAC RNAi. To analyze resulting changes microarray analysis, qRT-PCR, western blotting, Co-IP, proliferation, apoptosis, differentiation, invasion assays and xenograft-mouse models were used.

Results

Class I HDACs are constitutively expressed in EwS. Patients with high levels of individual class I HDAC expression show decreased overall survival. CRISPR/Cas9 class I HDAC knockout of individual HDACs such as HDAC1 and HDAC2 inhibited invasiveness, and blocked local tumor growth in xenograft mice. Microarray analysis demonstrated that treatment with individual HDAC inhibitors (HDACi) blocked an EWS-FLI1 specific expression profile, while Entinostat in addition suppressed metastasis relevant genes. EwS cells demonstrated increased susceptibility to treatment with chemotherapeutics including Doxorubicin in the presence of HDACi. Furthermore, HDACi treatment mimicked RNAi of EZH2 in EwS. Treated cells showed diminished growth capacity, but an increased endothelial as well as neuronal differentiation ability. HDACi synergizes with EED inhibitor (EEDi) in vitro and together inhibited tumor growth in xenograft mice. Co-IP experiments identified HDAC class I family members as part of a regulatory complex together with PRC2.

Conclusions

Class I HDAC proteins seem to be important mediators of the pathognomonic EWS-ETS-mediated transcription program in EwS and in combination therapy, co-treatment with HDACi is an interesting new treatment opportunity for this malignant disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02125-z.

Key auxin response factor (ARF) genes constraining wheat tillering of mutant dmc

Tillering ability is a key agronomy trait for wheat (Triticum aestivum L.) production. Studies on a dwarf monoculm wheat mutant (dmc) showed that ARF11 played an important role in tillering of wheat. In this study, a total of 67 ARF family members were identified and clustered to two main classes with four subgroups based on their protein structures. The promoter regions of T. aestivum ARF (TaARF) genes contain a large number of cis-acting elements closely related to plant growth and development, and hormone response. The segmental duplication events occurred commonly and played a major role in the expansion of TaARFs. The gene collinearity degrees of the ARFs between wheat and other grasses, rice and maize, were significantly high. The evolution distances among TaARFs determine their expression profiles, such as homoeologous genes have similar expression profiles, like TaARF4-3A-1, TaARF4-3A-2 and their homoeologous genes. The expression profiles of TaARFs in various tissues or organs indicated TaARF3, TaARF4, TaARF9 and TaARF22 and their homoeologous genes played basic roles during wheat development. TaARF4, TaARF9, TaARF12, TaARF15, TaARF17, TaARF21, TaARF25 and their homoeologous genes probably played basic roles in tiller development. qRT-PCR analyses of 20 representative TaARF genes revealed that the abnormal expressions of TaARF11 and TaARF14 were major causes constraining the tillering of dmc. Indole-3-acetic acid (IAA) contents in dmc were significantly less than that in Guomai 301 at key tillering stages. Exogenous IAA application significantly promoted wheat tillering, and affected the transcriptions of TaARFs. These data suggested that TaARFs as well as IAA signaling were involved in controlling wheat tillering. This study provided valuable clues for functional characterization of ARFs in wheat.

The Identification of Gene Expression Profiles Associated with Granulomatous Mastitis

Background

Granulomatous mastitis (GM) is a rare chronic inflammatory disease of the breast. The current therapeutic effects of the antibiotic therapy and surgical or immunomodulatory (steroid) treatment are normally poor due to the unclear etiology.

Method

This study aimed to identify the differentially expressed mRNAs in GM tissues using RNA sequencing and further explored the functions of differentially expressed mRNAs resulting in GM. Moreover, we revealed the relationship between GM and breast cancer by shared highly expressed genes in GM tissues and breast cancer tissues.

Results

A total of 12,115 mRNAs were analyzed in the whole expression profile, and 207 mRNAs (136 upregulated and 71 downregulated mRNAs) were differently expressed between the GM tissues and normal tissues. The enrichment analysis showed that the differentially expressed mRNAs were enriched in the biological processes and played a significant role in the immune system. Besides, the genes expressed significantly highly in breast cancer tissues are found to be enriched with GM genes, which may explain the similar clinical features between breast cancer and GM. We also found that the HSD11B1 gene which was differentially expressed in GM was used as drug target of prednisone, which is a common treatment for GM.

Conclusion

This study is the first to use sequencing technology to elucidate the genetic mechanisms of GM. The finding of this study may have potential value in GM diagnosis and also provides potential drug targets for GM treatment.

Genome-wide analysis and expression profiles of PdeMYB transcription factors in colored-leaf poplar (Populus deltoids)

BACKGROUND

MYB transcription factors, comprising one of the largest transcription factor families in plants, play many roles in secondary metabolism, especially in anthocyanin biosynthesis. However, the functions of the PdeMYB transcription factor in colored-leaf poplar remain elusive.

RESULTS

In the present study, genome-wide characterization of the PdeMYB genes in colored-leaf poplar (Populus deltoids) was conducted. A total of 302 PdeMYB transcription factors were identified, including 183 R2R3-MYB, five R1R2R3-MYB, one 4R-MYB, and 113 1R-MYB transcription factor genes. Genomic localization and paralogs of PdeMYB genes mapped 289 genes on 19 chromosomes, with collinearity relationships among genes. The conserved domain, gene structure, and evolutionary relationships of the PdeMYB genes were also established and analyzed. The expression levels of PdeMYB genes were obtained from previous data in green leaf poplar (L2025) and colored leaf poplar (QHP) as well as our own qRT-PCR analysis data in green leaf poplar (L2025) and colored leaf poplar (CHP), which provide valuable clues for further functional characterization of PdeMYB genes.

CONCLUSIONS

The above results provide not only comprehensive insights into the structure and functions of PdeMYB genes but also provide candidate genes for the future improvement of leaf colorization in Populus deltoids.

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.

Genome-wide identification of the MADS-box transcription factor family in autotetraploid cultivated alfalfa (Medicago sativa L.) and expression analysis under abiotic stress

Background

Alfalfa, the “queen of forage”, is the most extensively cultivated forage legume in the world. The development and yield of alfalfa are seriously limited by abiotic stress. MADS-box transcription factors are one of the largest gene families and play a pivotal role in plant development and abiotic stress. However, little is known regarding the MADS-box transcription factors in autotetraploid cultivated alfalfa.

Results

In the present study, we identified 120 MsMADS-box genes in the alfalfa genome. Phylogenetic analysis indicated that 75 type-I MsMADS-box genes were classified into the Mα, Mβ, and Mγ subgroups, and 45 type-II MsMADS-box genes were classified into 11 subgroups. The promoter region of MsMADS-box genes containing several hormone and stress related elements. Chromosomal location analysis revealed that 117 MsMADS-box genes were unevenly distributed on 32 chromosomes, and the remaining three genes were located on unmapped scaffolds. A total of nine pairs of segmental duplications and four groups of tandem duplications were found. Expression analysis showed that MsMADS-box genes were differentially expressed in various tissues and under abiotic stresses. qRT-PCR analysis revealed that the expression profiles of eight selected MsMADS-box genes were distinct under various stresses.

Conclusions

In this study, MsMADS-box genes were identified in the cultivated alfalfa genome based on autotetraploid level, and further confirmed by Gene Ontology (GO) analysis, phylogenetic analysis, sequence features and expression analysis. Taken together, these findings will provide clues for further study of MsMADS-box functions and alfalfa molecular breeding.

Our study is the first to systematically identify and characterize the MADS-box transcription factors in autotetraploid cultivated alfalfa (Medicago sativa L.), and eight MsMADS-box genes were significantly involved in response to various stresses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07911-9.

Genome-wide characterization and expression profiling of the PDR gene family in tobacco (Nicotiana tabacum)

The pleiotropic drug resistance (PDR) proteins of the ATP-binding cassette (ABC) family play essential roles in physiological processes and have been characterized in many plant species. However, no comprehensive investigation of tobacco (Nicotiana tabacum), an important economic crop and a useful model plant for scientific research, has been presented. We identified 32 PDR genes in the tobacco genome and explored their domain organization, chromosomal distribution and evolution, promoter cis-elements, and expression profiles. A phylogenetic analysis revealed that tobacco has a significantly expanded number of PDR genes involved in plant defense. It also revealed that two tobacco PDR proteins may function as strigolactone transporters to regulate shoot branching, and several NtPDR genes may be involved in cadmium transport. Moreover, tissue expression profiles of NtPDR genes and their responses to several hormones and abiotic stresses were assessed using quantitative real-time PCR. Most of the NtPDR genes were regulated by jasmonate or salicylic acid, suggesting the important regulatory roles of NtPDRs in plant defense and secondary metabolism. They were also responsive to abiotic stresses, like drought and cold, and there was a strong correlation between the presence of promoter cis-elements and abiotic/biotic stress responses. These results provide useful clues for further in-depth studies on the functions of the tobacco PDR genes.

Systematic analysis of differentially expressed ZmMYB genes related to drought stress in maize

MYB transcription factors play pivotal roles in hormone conduction signaling and abiotic stress response. In this study, 54 differentially expressed ZmMYB genes were identified and comprehensive analyses were conducted including gene's structure, chromosomal localization, phylogenetic tree, motif prediction, cis-elements and expression patterns. The results showed that 54 genes were unevenly distributed on 10 chromosomes and classified into eleven main subgroups by phylogenetic analysis, supported by motif and exon/intron analyses. The mainly stress-related cis-elements were ABRE, ARE, MBS and DRE-core. In addition, 8 core ZmMYB genes were identified by co-expression network. qRT-PCR results showed that the 8 ZmMYB genes exhibited different expression levels under different abiotic stresses, indicating that they were responsive to various abiotic stress. These results will provide insight for further functional investigation of ZmMYB genes.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12298-021-01013-2.

A predominant isoform of fructokinase, HbFRK2, is involved in Hevea brasiliensis (para rubber tree) latex yield and regeneration

Fructokinase (FRK) mediates fructose phosphorylation to regulate the carbon flow and its assignment to sink tissues. Out of five HbFRKs in the genome of the rubber tree, three (HbFRK1-3) that were highly expressed in latex (cytoplasm of laticifers) were isolated and examined. According to phylogenetic analysis and intracellular location experiment, both HbFRK2 and HbFRK3 were highly possible to be expressed in cytosol, while HbFRK1 was in plastid. As the predominant isoform in laticifers, HbFRK2 had the highest transcripts, followed by HbFRK3 and HbFRK1. In enzymatic function, HbFRK2 also showed the highest affinity for fructose. To examine the roles of FRKs in latex yield and regeneration, changes in HbFRKs were examined when latex outflow from the trees were increased through two experimental interventions. In the first approach, tapping was initiated on previously untapped trees, resulting in latex yield increasing with consecutive tapping at the initial stage before it stabilized. In the second approach, latex yield from trees that were already in regular tapping was stimulated by treatment with the ethylene-based yield stimulant, ethephon. Using either method to induce an increase in latex yield, the abundance of HbFRK2 and HbFRK3 in transcripts, was increased. This development, which was especially marked in HbFRK2, may reflect a strengthening of glycolysis to meet the carbon flux and energy demands for increased rubber biosynthesis to replace rubber lost in the increased latex yield. Our results, therefore, suggest that HbFRK2 plays a critical role in fructose catabolism to facilitate rubber regeneration in the commercially exploited rubber tree.

Key wheat GRF genes constraining wheat tillering of mutant dmc

Tillering is a key agronomy trait for wheat (Triticum aestivum L.) production. Previously, we have reported a dwarf-monoculm wheat mutant (dmc) obtained from cultivar Guomai 301 (wild type, WT), and found growth regulating factors (GRFs) playing important roles in regulating wheat tillering. This study is to systematically investigate the roles of all the wheat GRFs (T. aestivum GRFs, TaGRFs) in regulating tillering, and screen out the key regulators. A total of 30 TaGRFs were identified and their physicochemical properties, gene structures, conserved domains, phylogenetic relationships and tissue expression profiles were analyzed. The expression levels of all the TaGRFs were significantly lower in dmc than those in WT at early tillering stage, and the abnormal expressions of TaGRF2-7(A, B, D), TaGRF5-7D, TaGRF10-6(A, B, D) and TaGRF11-2A were major causes constraining the tillering of dmc. The transcriptions of TaGRFs were significantly affected by exogenous indole acetic acid (IAA) and gibberellin acid (GA3) applications, which suggested that TaGRFs as well as IAA, GA signaling were involved in controlling wheat tillering. This study provided valuable clues for functional characterization of GRF genes in wheat.

Antennal transcriptome analysis of olfactory genes and characterizations of odorant binding proteins in two woodwasps, Sirex noctilio and Sirex nitobei (Hymenoptera: Siricidae)

BACKGROUND

The woodwasp Sirex noctilio Fabricius is a major quarantine pest worldwide that was first discovered in China in 2013 and mainly harms Pinus sylvestris var. mongolica Litv.. S. nitobei Matsumura is a native species in China and is closely related to S. noctilio. Recently, the two woodwasps species were found attacking the P. sylvestris var. mongolica Litv in succession. The olfactory system is the foundation of insect behavior. Olfactory genes were identified through antennal transcriptome analysis. The expression profiles odorant binding proteins (OBPs) were analyzed with RT-qPCR.

RESULTS

From our transcriptome analysis, 16 OBPs, 7 chemosensory proteins (CSPs), 41 odorant receptors (ORs), 8 gustatory receptors (GRs), 13 ionotropic receptors (IRs), and one sensory neuron membrane protein (SNMP) were identified in S. noctilio, while 15 OBPs, 6 CSPs, 43 ORs, 10 GRs, 16 IRs, and 1 SNMP were identified in S. nitobei. Most of the olfactory genes identified in two species were homologous. However, some species-specific olfactory genes were identified from the antennal transcriptomes, including SnocOBP13, SnocCSP6, SnocOR26, SnocGR2, SnocIR7 in S. noctilio and SnitGR9, SnitGR11, SnitIR17 in S. nitobei. In total, 14 OBPs were expressed primarily in the antennae. SnocOBP9 and SnitOBP9, identified as PBP homologues, were sex-biased expression in two siricid, but with different pattern. SnocOBP11 and SnitOBP11 were highly expressed in antennae and clearly expressed in external genitalia. SnocOBP7 and SnitOBP7 were highly expressed in male genitalia. SnocOBP3 and SnocOBP10 were highly expressed in female genitalia and male heads, while SnitOBP3 and SnitOBP10 did not show obvious tissue bias.

CONCLUSION

We analyzed 86 and 91 olfactory genes from S. noctilio and S. nitobei, respectively. Most of the olfactory genes identified were homologous, but also some species-specific olfactory genes were identified, which indicated the similarities and differences of the molecular mechanisms between the two closely-related species. Different expression in the antennae, external genitals or heads, exhibiting an obvious sex bias, suggested their different role in recognizing sex pheromones or plant volatiles. Species-specific expression for several OBPs genes may suggest that they strengthened or lost their original function during species differentiation, resulting in olfactory differences between the two species.

Molecular characterization, expression and functional analysis of acyl-CoA-binding protein gene family in maize (Zea mays)

BACKGROUND

Acyl-CoA-binding proteins (ACBPs) possess a conserved acyl-CoA-binding (ACB) domain that facilitates binding to acyl-CoA esters and trafficking in eukaryotic cells. Although the various functions of ACBP have been characterized in several plant species, their structure, molecular evolution, expression profile, and function have not been fully elucidated in Zea mays L.

RESULTS

Genome-wide analysis identified nine ZmACBP genes in Z. mays, which could be divided into four distinct classes (class I, class II, class III, and class IV) via construction of a phylogenetic tree that included 48 ACBP genes from six different plant species. Transient expression of a ZmACBP-GFP fusion protein in tobacco (Nicotiana tabacum) epidermal cells revealed that ZmACBPs localized to multiple different locations. Analyses of expression profiles revealed that ZmACBPs exhibited temporal and spatial expression changes during abiotic and biotic stresses. Eight of the nine ZmACBP genes were also found to have significant association with agronomic traits in a panel of 500 maize inbred lines. The heterologous constitutive expression of ZmACBP1 and ZmACBP3 in Arabidopsis enhanced the resistance of these plants to salinity and drought stress, possibly through alterations in the level of lipid metabolic and stress-responsive genes.

CONCLUSION

The ACBP gene family was highly conserved across different plant species. ZmACBP genes had clear tissue and organ expression specificity and were responsive to both biotic and abiotic stresses, suggesting their roles in plant growth and stress resistance.

Genome-wide identification and analysis of cystatin family genes in Sorghum (Sorghum bicolor (L.) Moench)

To set a systematic study of the Sorghum cystatins (SbCys) gene family, a genome-wide analysis of the SbCys family genes was performed by bioinformatics-based methods. In total, 18 SbCys genes were identified in Sorghum, which were distributed unevenly on chromosomes, and two genes were involved in a tandem duplication event. All SbCys genes had similar exon/intron structure and motifs, indicating their high evolutionary conservation. Transcriptome analysis showed that 16 SbCys genes were expressed in different tissues, and most genes displayed higher expression levels in reproductive tissues than in vegetative tissues, indicating that the SbCys genes participated in the regulation of seed formation. Furthermore, the expression profiles of the SbCys genes revealed that seven cystatin family genes were induced during Bipolaris sorghicola infection and only two genes were responsive to aphid infestation. In addition, quantitative real-time polymerase chain reaction (qRT-PCR) confirmed that 17 SbCys genes were induced by one or two abiotic stresses (dehydration, salt, and ABA stresses). The interaction network indicated that SbCys proteins were associated with several biological processes, including seed development and stress responses. Notably, the expression of SbCys4 was up-regulated under biotic and abiotic stresses, suggesting its potential roles in mediating the responses of Sorghum to adverse environmental impact. Our results provide new insights into the structural and functional characteristics of the SbCys gene family, which lay the foundation for better understanding the roles and regulatory mechanism of Sorghum cystatins in seed development and responses to different stress conditions.

Identification and Transcriptional Analysis of Zinc Finger-Homeodomain (ZF-HD) Family Genes in Cucumber

Zinc finger-homeodomain (ZF-HD) proteins encode a family of plant-specific transcription factors that play essential roles in regulating plant growth and development as well as responses to abiotic/biotic stresses by activating or repressing the target genes. In this study, genome-wide characterization and expression profiling of the ZF-HD gene family in cucumber (Cucumis sativus) were performed for the first time. By using bioinformatics approaches, a total of 13 ZF-HD genes (designated as CsMIF1-CsMIF3 and CsZHD1-CsZHD10) were identified in the cucumber genome, which were unevenly distributed on six chromosomes. According to the phylogenetic analysis of cucumber and other species, they were divided into two distinct families, MINI ZINC FINGER (MIF) and zinc finger-homeodomain (ZHD), and the ZHD family was further divided into six subfamilies (ZHDI-ZHDVI). CsZF-HD members were mostly conserved in each subfamily with minor variations in motif distribution, and gene structure analysis showed that the CsZF-HD genes had only one intron or no intron at all. Expression analysis showed that most CsZF-HD genes had tissue-specific expression patterns, and some of them exhibited highly variable expression during fruit development. qRT-PCR results indicated that the selected CsZF-HD genes were responsive to drought stress, and some of them were differentially expressed in response to the inoculation of powdery mildew (PM) and downy mildew (DM) based on publicly available RNA-seq data. The results lay the foundation for further functional analysis of the ZF-HD genes and explore their potential application to the improvement of stress tolerance in cucumber.