Genome-Wide Identification and Function of Aquaporin Genes During Dormancy and Sprouting Periods of Kernel-Using Apricot (Prunus armeniaca L.)

Aquaporins (AQPs) are essential channel proteins that play a major role in plant growth and development, regulate plant water homeostasis, and transport uncharged solutes across biological membranes. In this study, 33 AQP genes were systematically identified from the kernel-using apricot (Prunus armeniaca L.) genome and divided into five subfamilies based on phylogenetic analyses. A total of 14 collinear blocks containing AQP genes between P. armeniaca and Arabidopsis thaliana were identified by synteny analysis, and 30 collinear blocks were identified between P. armeniaca and P. persica. Gene structure and conserved functional motif analyses indicated that the PaAQPs exhibit a conserved exon-intron pattern and that conserved motifs are present within members of each subfamily. Physiological mechanism prediction based on the aromatic/arginine selectivity filter, Froger’s positions, and three-dimensional (3D) protein model construction revealed marked differences in substrate specificity between the members of the five subfamilies of PaAQPs. Promoter analysis of the PaAQP genes for conserved regulatory elements suggested a greater abundance of cis-elements involved in light, hormone, and stress responses, which may reflect the differences in expression patterns of PaAQPs and their various functions associated with plant development and abiotic stress responses. Gene expression patterns of PaAQPs showed that PaPIP1-3, PaPIP2-1, and PaTIP1-1 were highly expressed in flower buds during the dormancy and sprouting stages of P. armeniaca. A PaAQP coexpression network showed that PaAQPs were coexpressed with 14 cold resistance genes and with 16 cold stress-associated genes. The expression pattern of 70% of the PaAQPs coexpressed with cold stress resistance genes was consistent with the four periods [Physiological dormancy (PD), ecological dormancy (ED), sprouting period (SP), and germination stage (GS)] of flower buds of P. armeniaca. Detection of the transient expression of GFP-tagged PaPIP1-1, PaPIP2-3, PaSIP1-3, PaXIP1-2, PaNIP6-1, and PaTIP1-1 revealed that the fusion proteins localized to the plasma membrane. Predictions of an A. thaliana ortholog-based protein–protein interaction network indicated that PaAQP proteins had complex relationships with the cold tolerance pathway, PaNIP6-1 could interact with WRKY6, PaTIP1-1 could interact with TSPO, and PaPIP2-1 could interact with ATHATPLC1G. Interestingly, overexpression of PaPIP1-3 and PaTIP1-1 increased the cold tolerance of and protein accumulation in yeast. Compared with wild-type plants, PaPIP1-3- and PaTIP1-1-overexpressing (OE) Arabidopsis plants exhibited greater tolerance to cold stress, as evidenced by better growth and greater antioxidative enzyme activities. Overall, our study provides insights into the interaction networks, expression patterns, and functional analysis of PaAQP genes in P. armeniaca L. and contributes to the further functional characterization of PaAQPs.

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Genome-Wide Analysis of the NAC Transcription Factor Gene Family Reveals Differential Expression Patterns and Cold-Stress Responses in the Woody Plant Prunus mume

Genes ◽

10.3390/genes9100494 ◽

2018 ◽

Vol 9 (10) ◽

pp. 494 ◽

Cited By ~ 17

Author(s):

Xiaokang Zhuo ◽

Tangchun Zheng ◽

Zhiyong Zhang ◽

Yichi Zhang ◽

Liangbao Jiang ◽

...

Keyword(s):

Cold Stress ◽

Gene Family ◽

Cold Tolerance ◽

Stress Responses ◽

Expression Profiles ◽

Expression Patterns ◽

Freezing Stress ◽

Prunus Mume ◽

Flower Bud ◽

Freezing Resistance

NAC transcription factors (TFs) participate in multiple biological processes, including biotic and abiotic stress responses, signal transduction and development. Cold stress can adversely impact plant growth and development, thereby limiting agricultural productivity. Prunus mume, an excellent horticultural crop, is widely cultivated in Asian countries. Its flower can tolerate freezing-stress in the early spring. To investigate the putative NAC genes responsible for cold-stress, we identified and analyzed 113 high-confidence PmNAC genes and characterized them by bioinformatics tools and expression profiles. These PmNACs were clustered into 14 sub-families and distributed on eight chromosomes and scaffolds, with the highest number located on chromosome 3. Duplicated events resulted in a large gene family; 15 and 8 pairs of PmNACs were the result of tandem and segmental duplicates, respectively. Moreover, three membrane-bound proteins (PmNAC59/66/73) and three miRNA-targeted genes (PmNAC40/41/83) were identified. Most PmNAC genes presented tissue-specific and time-specific expression patterns. Sixteen PmNACs (PmNAC11/19/20/23/41/48/58/74/75/76/78/79/85/86/103/111) exhibited down-regulation during flower bud opening and are, therefore, putative candidates for dormancy and cold-tolerance. Seventeen genes (PmNAC11/12/17/21/29/42/30/48/59/66/73/75/85/86/93/99/111) were highly expressed in stem during winter and are putative candidates for freezing resistance. The cold-stress response pattern of 15 putative PmNACs was observed under 4 °C at different treatment times. The expression of 10 genes (PmNAC11/20/23/40/42/48/57/60/66/86) was upregulated, while 5 genes (PmNAC59/61/82/85/107) were significantly inhibited. The putative candidates, thus identified, have the potential for breeding the cold-tolerant horticultural plants. This study increases our understanding of functions of the NAC gene family in cold tolerance, thereby potentially intensifying the molecular breeding programs of woody plants.

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Carotenoid Cleavage Dioxygenases: Identification, Expression, and Evolutionary Analysis of This Gene Family in Tobacco

International Journal of Molecular Sciences ◽

10.3390/ijms20225796 ◽

2019 ◽

Vol 20 (22) ◽

pp. 5796

Author(s):

Qianqian Zhou ◽

Qingchang Li ◽

Peng Li ◽

Songtao Zhang ◽

Che Liu ◽

...

Keyword(s):

Gene Family ◽

Physiological Stress ◽

Expression Patterns ◽

Functional Characterization ◽

Hormone Treatment ◽

Nicotiana Sylvestris ◽

Regulatory Elements ◽

Evolutionary Analysis ◽

Comprehensive Overview ◽

Carotenoid Cleavage Dioxygenases

Carotenoid cleavage dioxygenases (CCDs) selectively catalyze carotenoids, forming smaller apocarotenoids that are essential for the synthesis of apocarotenoid flavor, aroma volatiles, and phytohormone ABA/SLs, as well as responses to abiotic stresses. Here, 19, 11, and 10 CCD genes were identified in Nicotiana tabacum, Nicotiana tomentosiformis, and Nicotiana sylvestris, respectively. For this family, we systematically analyzed phylogeny, gene structure, conserved motifs, gene duplications, cis-elements, subcellular and chromosomal localization, miRNA-target sites, expression patterns with different treatments, and molecular evolution. CCD genes were classified into two subfamilies and nine groups. Gene structures, motifs, and tertiary structures showed similarities within the same groups. Subcellular localization analysis predicted that CCD family genes are cytoplasmic and plastid-localized, which was confirmed experimentally. Evolutionary analysis showed that purifying selection dominated the evolution of these genes. Meanwhile, seven positive sites were identified on the ancestor branch of the tobacco CCD subfamily. Cis-regulatory elements of the CCD promoters were mainly involved in light-responsiveness, hormone treatment, and physiological stress. Different CCD family genes were predominantly expressed separately in roots, flowers, seeds, and leaves and exhibited divergent expression patterns with different hormones (ABA, MeJA, IAA, SA) and abiotic (drought, cold, heat) stresses. This study provides a comprehensive overview of the NtCCD gene family and a foundation for future functional characterization of individual genes.

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Identification of cold stress responsive microRNAs in cold tolerant and susceptible Hemerocallis fulva by high throughput sequencing

10.21203/rs.3.rs-41470/v1 ◽

2020 ◽

Author(s):

Changbing Huang ◽

Chun Jiang ◽

limin Jin ◽

Huanchao Zhang

Keyword(s):

Low Temperature ◽

Cold Stress ◽

Cold Tolerance ◽

Temperature Stress ◽

Stress Responses ◽

Target Genes ◽

Low Temperature Stress ◽

Differentially Expressed ◽

Differentially Expressed Mirnas ◽

Cold Tolerant

Abstract Background:Hemerocallis fulva is a perennial herb belonging to Hemerocallis of Hemerocallis. Because of the large and bright colors, it is often used as a garden ornamental plant. But most varieties of H. fulva on the market will wither in winter, which will affect their beauty. It is very important to study the effect of low temperature stress on the physiological indexes of H. fulva and understand the cold tolerance of different H. fulva. MiRNA is a kind of endogenous non coding small molecular RNA with length of 21-24nt. It mainly inhibits protein translation by cutting target genes, and plays an important role in the development of organisms, gene expression and biological stress. Low temperature is the main abiotic stress affecting the production of H. fulva in China, which hinders the growth and development of plants. A comprehensive understanding of the expression pattern of microRNA in H. fulva under low temperature stress can improve our understanding of microRNA mediated stress response. Although there are many studies on miRNAs of various plants under cold stress at home and abroad, there are few studies on miRNAs related to cold stress of H. fulva. It is of great significance to explore the cold stress resistant gene resources of H. fulva, especially the identification and functional research of miRNA closely related to cold stress, for the breeding of excellent H. fulva.Results A total of 5619 cold-responsive miRNAs, 315 putative novel and 5 304 conserved miRNAs, were identified from the leaves and roots of two different varieties ‘Jinyan’ (cold-tolerant) and ‘Lucretius ’ (cold-sensitive), which were stressed under -4 oC for 24 h. Twelve conserved and three novel miRNAs (novel-miR10, novel-miR19 and novel-miR48) were differentially expressed in leaves of ‘Jinyan’ under cold stress. Novel-miR19, novel-miR29 and novel-miR30 were up-regulated in roots of ‘Jinyan’ under cold stress. Thirteen and two conserved miRNAs were deferentially expressed in leaves and roots of ‘Lucretius’ after cold stress. The deferentially expressed miRNAs between two cultivars under cold stress include novel miRNAs and the members of the miR156, miR166 and miR319 families. A total of 6 598 target genes for 6 516 known miRNAs and 82 novel miRNAs were predicted by bioinformatic analysis, mainly involved in metabolic processes and stress responses. Ten differentially expressed miRNAs and predicted target genes were confirmed by quantitative reverse transcription PCR(q-PCR), and the expressional changes of target genes were negatively correlated to differentially expressed miRNAs. Our data indicated that some candidate miRNAs (e.g., miR156a-3-p, miR319a, and novel-miR19) may play important roles in plant response to cold stress.Conclusions Our study indicates that some putative target genes and miRNA mediated metabolic processes and stress responses are significant to cold tolerance in H. fulva.

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Identification of the Cytosolic Glucose-6-Phosphate Dehydrogenase Gene from Strawberry Involved in Cold Stress Response

International Journal of Molecular Sciences ◽

10.3390/ijms21197322 ◽

2020 ◽

Vol 21 (19) ◽

pp. 7322

Author(s):

Yunting Zhang ◽

Mengwen Luo ◽

Lijuan Cheng ◽

Yuanxiu Lin ◽

Qing Chen ◽

...

Keyword(s):

Cold Stress ◽

Stress Responses ◽

Expression Patterns ◽

Plant Stress ◽

Bioinformatic Analysis ◽

Ros Generation ◽

Ros Scavenging ◽

Dehydrogenase Gene ◽

Plant Stress Responses ◽

Glucose 6 Phosphate Dehydrogenase

Glucose-6-phosphate dehydrogenase (G6PDH) plays an important role in plant stress responses. Here, five FaG6PDH sequences were obtained in strawberry, designated as FaG6PDH-CY, FaG6PDH-P1, FaG6PDH-P1.1, FaG6PDH-P2 and FaG6PDH-P0, which were divided into cytosolic (CY) and plastidic (P) isoforms based on the bioinformatic analysis. The respective FaG6PDH genes had distinct expression patterns in all tissues and at different stages of fruit development. Notably, FaG6PDH-CY was the most highly expressed gene among five FaG6PDH members, indicating it encoded the major G6PDH isoform throughout the plant. FaG6PDH positively regulated cold tolerance in strawberry. Inhibition of its activity gave rise to greater cold-induced injury in plant. The FaG6PDH-CY transcript had a significant increase under cold stress, similar to the G6PDH enzyme activity, suggesting a principal participant in response to cold stress. Further study showed that the low-temperature responsiveness (LTR) element in FaG6PDH-CY promoter can promote the gene expression when plant encountered cold stimuli. Besides, FaG6PDH-CY was involved in regulating cold-induced activation of antioxidant enzyme genes (FaSOD, FaCAT, FaAPX and FaGR) and RBOH-dependent ROS generation. The elevated FaG6PDH-CY enhanced ROS-scavenging capability of antioxidant enzymes to suppress ROS excessive accumulation and relieved the oxidative damage, eventually improving the strawberry resistance to cold stress.

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Identification and Expression Analysis of the NAC Gene Family in Coffea canephora

Agronomy ◽

10.3390/agronomy9110670 ◽

2019 ◽

Vol 9 (11) ◽

pp. 670 ◽

Cited By ~ 4

Author(s):

Dong ◽

Jiang ◽

Yang ◽

Xiao ◽

Bai ◽

...

Keyword(s):

Cold Stress ◽

Gene Family ◽

Stress Responses ◽

Developmental Stages ◽

Expression Patterns ◽

Coffea Canephora ◽

Coffee Bean ◽

Systematic Analysis ◽

Nac Gene Family ◽

Basic Features

The NAC gene family is one of the largest families of transcriptional regulators in plants, and it plays important roles in the regulation of growth and development as well as in stress responses. Genome-wide analyses have been performed in diverse plant species, but there is still no systematic analysis of the NAC genes of Coffea canephora Pierre ex A. Froehner. In this study, we identified 63 NAC genes from the genome of C. canephora. The basic features and comparison analysis indicated that the NAC gene members increased via duplication events during the evolution of the plant. Phylogenetic analysis divided the NAC proteins from C. canephora, Arabidopsis and rice into 16 subgroups. Analysis of the expression patterns of CocNACs under cold stress and coffee bean development indicated that 38 CocNACs were differentially expressed under cold stress; six genes may play important roles in the process of cold acclimation, and four genes among 54 CocNACs showing a variety of expression patterns during different developmental stages of coffee beans may be positively related to the bean development. This study can expand our understanding of the functions of the CocNAC gene family in cold responses and bean development, thereby potentially intensifying the molecular breeding programs of Coffea spp. plants.

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Different Responses of Cytoplasmic and Endoplasmic Reticulum Hsp90 Genes from Eogystia hippophaecola (Lepidoptera: Cossidae) to Cold Stress

Forests ◽

10.3390/f10111039 ◽

2019 ◽

Vol 10 (11) ◽

pp. 1039

Author(s):

Qianqian Wang ◽

Jing Tao ◽

Yurong Li ◽

Yabei Xu ◽

Xinhai Liu ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Amino Acid ◽

Low Temperature ◽

Cold Stress ◽

Cold Tolerance ◽

Response Times ◽

Expression Patterns ◽

Amino Acid Sequences ◽

Sea Buckthorn ◽

Open Reading Frames

Eogystia hippophaecola Hua, Chou, Fang et Chen (Lepidoptera: Cossidae) is an important borer pest of the sea buckthorn forest (Hippophae rhamnoides L.) in China. Its larvae, which are highly cold tolerant, mainly overwinter in sea buckthorn roots. Heat shock proteins (Hsps) are important molecular chaperones that have been linked to cold tolerance in insects. In this study, we cloned the open reading frames (ORFs) of two Hsp90 genes from E. hippophaecola, EhHsp90-1 and EhHsp90-2, and analyzed their expression under cold stress by qRT-PCR. EhHsp90-1 and EhHsp90-2 are 2154 and 2346 bp in length, respectively, encoding 717 and 781 amino acids. The deduced amino acid sequences contain the conserved signature sequences of the Hsp90 family and the C-terminus characteristic sequence of cytoplasmic or endoplasmic reticulum Hsp90 protein. Phylogenetic analysis revealed the amino acid sequences of EhHsp90-1 and EhHsp90-2 were very similar to the corresponding proteins from Lepidoptera. Under various low-temperature treatments lasting 2 h, EhHsp90-1 and EhHsp90-2 exhibited similar expression patterns, increasing first and then decreasing. At −5 °C, EhHsp90-1 was significantly up-regulated after 12 h, whereas EhHsp90-2 was up-regulated after just 1 h and reached its highest level at 2 h; however, the overall degree of upregulation was greater for EhHsp90-1. Subsequently, the expression level of EhHsp90-2 fluctuated with time. Our results suggest that the two Hsp90s play important roles in E. hippophaecola larvae response to cold stress, but that their response times and the magnitudes of their responses to low-temperature stress differed significantly, providing a theoretical basis for further studying the molecular mechanism of cold tolerance in E. hippophaecola larvae.

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A comprehensive analysis of cotton VQ gene superfamily reveals their potential and extensive roles in regulating cotton abiotic stress

10.21203/rs.3.rs-38226/v1 ◽

2020 ◽

Author(s):

Shuxun Yu ◽

Pengyun Chen ◽

Fei wei ◽

Shuaishuai Cheng ◽

Liang Ma ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Responses ◽

Expression Patterns ◽

Regulatory Elements ◽

Abiotic Stress Response ◽

Salt And Drought Stress ◽

Solid Foundation ◽

Underlying Mechanisms ◽

Peg Stress ◽

Insight Into

Abstract Background Valine-glutamine (VQ) motif-containing proteins play important roles in plant growth, development and abiotic stress response. For many plant species, the VQ genes have been identified and their functions have been described. However, little is known about the origin, evolution, and functions (and underlying mechanisms) of the VQ family genes in cotton. Results In this study, we comprehensively analyzed the characteristics of 268 VQ genes from four Gossypium genomes and found that the VQ proteins evolved into ten clades, and each clade had a similar structural and conservative motif. The expansion of the VQ gene was mainly through segmental duplication, followed by dispersal. Expression analysis revealed that the VQ genes play important roles in response to salt and drought stress, especially GhVQ18 and GhVQ84 were significantly high expression in PEG stress and salt stress. Further analysis showed that GhVQ genes were co-expressed with GhWRKY transcription factors (TFs), and microRNAs (miRNAs) could hybridize to their cis-regulatory elements. Conclusions The results in this study broaden our understanding of the VQ gene family in plants, and the analysis of the structure, conserved elements, and expression patterns of the VQ genes provide a solid foundation for exploring their specific functions in the abiotic stress responses in cotton. Our study provides significant insight into the potential functions of VQ genes in cotton.

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Genome-wide identification and characterization of lectin receptor-like kinase gene family in cucumber and expression profiling analysis under different treatments

10.21203/rs.2.20023/v1 ◽

2020 ◽

Author(s):

Duo Lv ◽

Gang Wang ◽

Yue Chen ◽

Liang-Rong Xiong ◽

Jing-Xian Sun ◽

...

Keyword(s):

Gene Family ◽

Stress Responses ◽

Expression Patterns ◽

Regulatory Elements ◽

Kinase Gene ◽

Cucumis Sativus L ◽

Lectin Receptor ◽

Genome Wide ◽

Cucumber Genome ◽

And Function

Abstract Background Lectin receptor-like kinases (LecRLKs) are a class of membrane proteins found in plants that are involved in diverse functions, including plant development and stress responses. Although LecRLK families have been identified in a variety of plants, a comprehensive analysis has not yet been undertaken in cucumber ( Cucumis sativus L.).Results In this study, 46 putative LecRLK genes were identified in cucumber genome, including 23 G-type, 22 L-type and 1 C-type LecRLK genes. They unequally distributed on all 7 chromosomes with a clustering trendency. Most of the genes in the cucumber LecRLK (Cs LecRLK) gene family lacked introns. In addition, there were many regulatory elements associated with phytohormone and stress on these genes’ promoters. Transcriptome data demonstrated that distinct expression patterns of CsLecRLK genes in various tissues. Furthermore, we found that each member of the CsLecRLK family had its own unique expression pattern under hormone and stress treatment by the quantitative real time PCR (qRT-PCR) analysis.Conclusion This study provides a better understanding of the evolution and function of LecRLK gene family in cucumber, and opens the possibility to explore the roles that LecRLK s might play in the life cycle of cucumber.

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Genome-wide identification, molecular evolution, and expression analysis provide new insights into the APETALA2/ethylene responsive factor (AP2/ERF) superfamily in Dimocarpus longan Lour

10.21203/rs.2.11288/v3 ◽

2019 ◽

Author(s):

Shuting Zhang ◽

Chen Zhu ◽

Yumeng Lyu ◽

Yan Chen ◽

Zihao Zhang ◽

...

Keyword(s):

Molecular Evolution ◽

Stress Responses ◽

Expression Patterns ◽

Functional Characterization ◽

Transcriptional Level ◽

Developmental Processes ◽

Genome Wide ◽

A Genome ◽

Dimocarpus Longan ◽

Ethylene Responsive Factor

Abstract Background: The APETALA2/ethylene responsive factor (AP2/ERF) superfamily members are transcription factors that regulate diverse developmental processes and stress responses in plants. They have been identified in many plants. However, little is known about the AP2/ERF superfamily in longan (Dimocarpus longan Lour.), which is an important tropical/subtropical evergreen fruit tree that produces a variety of bioactive compounds with rich nutritional and medicinal value. We conducted a genome-wide analysis of the AP2/ERF superfamily and its roles in somatic embryogenesis (SE) and developmental processes in longan. Results: A genome-wide survey of the AP2/ERF superfamily was carried out to discover its evolution and function in longan. We identified 125 longan AP2/ERF genes and classified them into the ERF (101 members), AP2 (19 members), RAV (four members) families, and one Soloist. The AP2 and Soloist genes contained one to ten introns, whereas 87 genes in the ERF and RAV families had no introns. Hormone signaling molecules such as methyl jasmonate (MeJA), abscisic acid (ABA), gibberellin, auxin, and salicylic acid (SA), and stress response cis-acting element low-temperature (55) and defense (49) boxes also were identified. We detected diverse single nucleotide polymorphisms (SNPs) between the 'Hong He Zi' (HHZ) and 'SI JI MI' (SJM) cultivars. The number of insertions and deletions (InDels) was far fewer than SNPs. The AP2 family members exhibited more alternative splicing (AS) events in different developmental processes of longan than members of the other families. Expression pattern analysis revealed that some AP2/ERF members regulated early SE and developmental processes in longan seed, root, and flower, and responded to exogenous hormones such as MeJA, SA, and ABA, and 2,4-D, a synthetic auxin. Protein interaction predictions indicated that the Baby Boom (BBM) transcription factor, which was up-regulated at the transcriptional level in early SE, may interact with the LALF/AGL15 network. Conclusions: The comprehensive analysis of molecular evolution and expression patterns suggested that the AP2/ERF superfamily may plays an important role in longan, especially in early SE, and in seed, root, flower, and young fruit. This systematic analysis provides a foundation for further functional characterization of the AP2/ERF superfamily with the aim of longan improvement.

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The rice annexin gene OsAnn5 is a positive regulator of cold stress tolerance at the seedling stage

10.21203/rs.3.rs-21726/v1 ◽

2020 ◽

Author(s):

chunxiu shen ◽

Zhiqun Que ◽

Qineng Lu ◽

Tao Liu ◽

Shengqiang Li ◽

...

Keyword(s):

Cold Stress ◽

Stress Tolerance ◽

Stress Responses ◽

Fluorescent Protein ◽

Functional Characterization ◽

Survival Rates ◽

Seedling Stage ◽

Positive Regulator ◽

Annexin Gene ◽

Green Fluorescent

Abstract Annexins exist widely in plants as multigene families and play critical roles in stress responses and a range of cellular processes. In this study, we report on the cloning and functional characterization of the rice annexin gene OsAnn5. We found that the expression of OsAnn5 was induced by cold stress treatment at the seedling stage of rice. GUS staining assay indicated that the expression of OsAnn5 was non tissue-specific and was detected in almost all rice tissues. Subcellular localization indicated that OsAnn5-GFP (green fluorescent protein) signals were found in the endoplasmic reticulum apparatus. Compared with wild type rice, overexpression of OsAnn5 significantly increased survival rates at the seedling stage under cold stress, while knocking out OsAnn5 using the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR associated proteins) mediated genome editing resulted in sensitivity to cold treatments. These results indicate that OsAnn5 is a positive regulator of cold stress tolerance at the seedling stage.

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