Genome-wide identification,molecular evolution,and expression divergence of the hexokinase gene family in apple

Hexokinase(HXK) is the first irreversible catalytic enzyme in the glycolytic pathway, which not only provides energy for plant growth and development but also serves as a signaling molecule in response to environmental changes. However, the evolutionary pattern of the HXK gene family in apple remains unknown. In this study, a total of nine HXK genes were identified in the Malus×domestica genome GDDH13 v1.1. The physiological and biochemical properties, exonintron structures, conserved motifs, and cis-elements of the MdHXK genes were determined. Predicted subcellular localization indicated that the MdHXK genes were mainly distributed in the mitochondria, cytoplasm, and nucleus. Gene duplication revealed that whole-genome duplication(WGD) and segmental duplication played vital roles in MdHXK gene family expansion. The ω values of pairwise MdHXK genes indicated that this family was subjected to strong purifying selection during apple domestication. Additionally, five subfamilies were classified, and recent/old duplication events were identified based on phylogenetic tree analysis. Different evolutionary rates were estimated among the various HXK subfamilies. Moreover, divergent expression patterns of the Md HXK genes in four source-sink tissues and at five different apple fruit developmental stages indicated that they play vital roles in apple fruit development and sugar accumulation. Our study provides a theoretical basis for future elucidation of the biological functions of the MdHXK genes during apple fruit development.     

Genome-wide identification and function analysis of the sucrose phosphate synthase MdSPS gene family in apple

Sucrose phosphate synthase (SPS) is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase (SPP) for sucrose synthesis, and it plays an essential role in energy provisioning during growth and development in plants as well as improving fruit quality. However, studies on the systematic analysis and evolutionary pattern of the SPS gene family in apple are still lacking. In the present study, a total of seven MdSPS and four MdSPP genes were identified from the Malus domestica genome GDDH13 v1.1. The gene structures and their promoter cis-elements, protein conserved motifs, subcellular localizations, physiological functions and biochemical properties were analyzed. A chromosomal location and gene-duplication analysis demonstrated that whole-genome duplication (WGD) and segmental duplication played vital roles in MdSPS gene family expansion. The Ka/Ks ratio of pairwise MdSPS genes indicated that the members of this family have undergone strong purifying selection during domestication. Furthermore, three SPS gene subfamilies were classified based on phylogenetic relationships, and old gene duplications and significantly divergent evolutionary rates were observed among the SPS gene subfamilies. In addition, a major gene related to sucrose accumulation (MdSPSA2.3) was identified according to the highly consistent trends in the changes of its expression in four apple varieties (‘Golden Delicious’, ‘Fuji’, ‘Qinguan’ and ‘Honeycrisp’) and the correlation between gene expression and soluble sugar content during fruit development. Furthermore, the virus-induced silencing of MdSPSA2.3 confirmed its function in sucrose accumulation in apple fruit. The present study lays a theoretical foundation for better clarifying the biological functions of the MdSPS genes during apple fruit development.     

苹果WRKY基因家族生物信息学及表达分析

【目的】鉴定苹果（Malus domesticaBorkh.）基因组上132个WRKY基因,为研究苹果WRKY转录因子在非生物和生物胁迫以及生长和发育过程中的调控作用奠定相关理论基础,也为进一步分析苹果WRKY基因提供信息。【方法】利用HMMER 3.0软件,通过WRKY保守域全蛋白序列PF03106用于鉴定苹果WRKY基因。采用WebLogo 3、DNAMAN 5.0、MapInspect、MEME和MEGA5.1等软件对其蛋白序列进行生物信息学分析。采用RT-PCR技术检测苹果WRKY基因的组织表达情况。【结果】鉴定得到132个苹果WRKY基因。分组鉴定和进化树分析结果显示,苹果WRKY蛋白分为I、II和III类型,I组共有24个成员可进一步分为I-C和I-N亚组,其锌指结构是C₂H₂类型（CX₄CX_22-23HXH）。II组含有1个WRKY区域共有79个成员,可进一步分为II-a、II-b、II-c、II-d和II-e亚组,分别有8、12、31、14和14个成员,其锌指结构为C₂H₂类型（CX_4-5CX₂₃HXH）。III组共有29个成员,其锌指结构为C₂HC类型（CX₇CX_23-24HXC）;WRKY结构域分析显示,其高度保守,绝大多数都含有WRKYGQK七肽和锌指结构;染色体定位分析显示,苹果WRKY分布于苹果17条染色体中,呈不均匀分布。染色体1和9上分布最多,为13个;其次是染色体12,分布12个;染色体2、5和14分布最少,为4个;基因结构分析表明,MdWRKY基因家族多数由2-5个外显子组成,基因结构进化高度保守;保守元件分析表明,MdWRKY基因家族包含10个保守元件：元件1-6为WRKY盒;元件7-10为未知盒。MdWRKY基因家族都包含有WRKY盒,I组中含有2个WRKY盒,II-a和II-b亚组中含有未知元件8,III组中含有未知元件7和9。半定量结果显示,12个MdWRKY均在根、茎、叶、花和果中表达,且呈现出多种相对表达模式。【结论】苹果WRKY基因家族结构高度保守,可能参与调控苹果生长和发育等过程。     

Rediscovery and analysis of Phytophthora carbohydrate esterase (CE) genes revealing their evolutionary diversity

A continuous co-evolutionary arms-race between pathogens and their host plants promotes the development of pathogenic factors by microbes, including carbohydrate esterase (CE) genes to overcome the barriers in plant cell walls. Identification of CEs is essential to facilitate their functional and evolutionary investigations; however, current methods may have a limit in detecting some conserved domains, and ignore evolutionary relationships of CEs, as well as do not distinguish CEs from proteases. Here, candidate CEs were annotated using conserved functional domains, and orthologous gene detection and phylogenetic relationships were used to identify new CEs in 16 oomycete genomes, excluding genes with protease domains. In our method, 41 new putative CEs were discovered comparing to current methods, including three CE4, 14 CE5, eight CE12, five CE13, and 11 CE14. We found that significantly more CEs were identified in Phytophthora than in Hyaloperonospora and Pythium, especially CE8, CE12, and CE13 that are putatively involved in pectin degradation. The abundance of these CEs in Phytophthora may be due to a high frequency of multiple-copy genes, supporting by the phylogenetic distribution of CE13 genes, which showed five units of Phytophthora CE13 gene clusters each displaying a species tree like topology, but without any gene from Hyaloperonospora or Pythium species. Additionally, diverse proteins associated with products of CE13 genes were identified in Phytophthora strains. Our analyses provide a highly effective method for CE discovery, complementing current methods, and have the potential to advance our understanding of function and evolution of CEs.     

大豆SBP基因家族的序列特征、表达及进化分析

SBP基因家族是植物所特有的一类重要转录因子,由多个成员组成,主要参与植物生长、发育以及多种生理生化过程.试验在大豆基因组中鉴定49个SBP基因,被命名为GmSBP1~49.基于生物信息学手段,对大豆该基因家族49个成员的基因结构、染色体定位、蛋白保守序列、亚细胞定位、表达情况及进化关系进行分析.序列分析表明,SBP基因家族成员分散于不同染色体上,不同基因具有不同个数的外显子,其数目变异范围为1~14;该家族蛋白含有5个保守基序,尽管与SBP结构域有所重叠,但它们能形成6种不同的组织模式,这说明该基因家族序列变异较为复杂.表达分析结果显示,除GmSBP2和GmSBP11等6个基因没有相应的EST外,其余基因都有转录活性;在具有转录活性的基因中,只有GmSBP46显示出组成型表达模式,剩余基因表现出不同程度的组织特异性表达模式.拟南芥、水稻和大豆SBP蛋白的进化树揭示该家族具有8个类群,其中E类群只包括大豆SBP基因,其他类群中大豆SBP基因数目也是最多,这充分说明大豆SBP基因家族起源与进化的复杂性.研究为大豆SBP基因功能研究提供线索     

西瓜PIP5K基因家族鉴定及其在雄性不育花蕾中的表达分析

为了挖掘西瓜磷脂酰肌醇4-磷酸5-激酶(PIP5K)基因的功能,利用生物信息学方法对西瓜PIP5K家族成员进行鉴定和特征分析,并对其在多个组织的表达模式进行分析研究。结果显示:西瓜基因组中含有8个PIP5K家族成员,分布在6条染色体上;多数基因定位在细胞质或细胞膜上;共线性分析发现4个 ClaPIP5K基因与5个 AtPIP5K基因存在共线关系,并且 ClaPIP5K基因间存在片段复制事件;进化树分析发现 ClaPIP5K基因和 AtPIP5K基因被分成4组,并且同一组内的基因具有相似的保守基序和基因结构;启动子分析发现 ClaPIP5K基因中含有激素和胁迫响应相关顺式作用元件;表达分析显示 ClaPIP5K基因在西瓜生长点、果柄、果肉、叶片、下胚轴、根以及花蕾等组织中表现出不同的表达水平。     

Identification and expression of the CEP gene family in apple (Malus×domestica)

Plant peptide hormones play important roles in plant growth and development. Among these hormones, the C-TERMINALLYENCODED PEPTIDE(CEP) belongs to a newly found peptide family that regulates root development in Arabidopsis as well as in other species. However, nothing is known about the CEP genes in apple(Malus×domestica, MdCEP). In this study, a total of 27 apple CEP genes were identified through a genome-wide analysis and were phylogenetically divided into three classes(Ⅰ, Ⅱ and Ⅲ). The predicted MdCEP genes were distributed across 10 of 17 chromosomes with different densities. Next, the gene structures and motif compositions of the MdCEP genes were analyzed. Subsequently, the expression analysis suggested that the MdCEP genes were highly activated in roots and that MdCEP23 may play an important role in regulating the growth and development of roots. Moreover, all of the MdCEP genes were responsive to multiple abiotic stresses, indicating that MdCEP genes may be involved with various aspects of physiological processes in apple. Nearly one-third of MdCEP genes had a significant response to low nitrogen treatment. Most of the MdCEP genes were up-regulated under stress, including mannitol, polyethylene glycol(PEG) and abscisic acid(ABA), suggesting that MdCEP genes may be involved in the drought stress response. This study provides insight into the putative functions of the MdCEP genes using a genome-wide analysis of the CEP gene family.     

苹果MADS-box转录因子的生物信息学及其在不同组织中的表达

【目的】分析已知苹果（Malus×domestica）MADS-box基因基本信息,研究其在不同组织中表达情况。【方法】利用NCBI数据库查询并获得苹果MADS-box基因,采用CLC Combined Workbench version 6、WebLogo 3、MEGA4.1、MapInspect和MEME等软件对其蛋白序列进行生物信息学分析。采用RT-PCR技术研究MdMADS基因在不同组织中的表达情况。【结果】共得到26个苹果MADS-box基因。MADS-box结构域分析显示,氨基酸10（I）、16-19（RQVT）、22-23（KR）、29-31（KKA）、33（E）、37-39（LCD）、42（V）和48（S）是保守不变的。保守元件分析表明,苹果MADS-box基因包含4个保守元件：元件1、3为MADS盒;元件2、4为K盒。所有苹果MADS-box蛋白都包含有MADS盒（除MdMADS9）和K盒。进化树分析结果显示,苹果MADS基因共分为5个亚组。MdMADS1、3、4、6、7、8、11、18属于SEP亚组;MdMADS2、5、12属于AP1亚组;MdMADS10、14、15、19、22和MdAGL属于AG亚组;MdMADS16、17、21、MdSOC1、MdSOC1a和MdSOC1c属于SOC1亚组;MdMADS13、23和MdPI属于AP3亚组;MdMADS20属于SVP亚组。染色体定位分析显示,MdMADS在8号染色体上分布最多,共有4个;其次是染色体2、14和17,均分布3个;染色体1、5、6、7、11和16均分布1个;染色体3、4、12和15则没有分布。RT-PCR结果分析显示,SEP和AGL亚组表达模式较为一致,主要在花和果实中表达;AP1亚组除在花和果实中表达外,在其它组织器官中也有表达。【结论】苹果MADS-box基因结构高度保守,多数成员参与调控花和果实发育过程。     

Genome-wide identification and expression analysis of GDSL esterase/lipase genes in tomato

The GDSL esterase/lipase family contains many functional genes that perform important biological functions in growth and development, morphogenesis, seed oil synthesis, and defense responses in plants. The expression of GDSL esterase/lipase genes can respond to biotic and abiotic stresses. Although GDSL esterase/lipase family genes have been identified and studied in other plants, they have not been identified and their functions remain unclear in tomato. This study is the first to identify 80 GDSL esterase/lipase family genes in tomato, which were named SlGELP1–80. These genes were mapped to their positions on the chromosomes and their physical and chemical properties, gene structure, phylogenetic relationships, collinear relationships, and cis-acting elements were analyzed. The spatiotemporal expression characteristics of the SlGELP genes in tomato were diverse. In addition, RNA-seq analysis indicated that the expression patterns of the SlGELP genes in tomato differed before and after inoculation with Stemphylium lycopersici. qRT-PCR was used to analyze the expression of five SlGELP genes after treatments with S. lycopersici, salicylic acid and jasmonic acid. Finally, this study was the first to identify and analyze GDSL esterase/lipase family genes in tomato via bioinformatics approaches, and these findings provide new insights for improving the study of plant disease resistance.     

Structure and expression analysis of the sucrose synthase gene family in apple

Sucrose synthases (SUS) are a family of enzymes that play pivotal roles in carbon partitioning, sink strength and plant development. A total of 11 SUS genes have been identified in the genome of Malus domestica (MdSUSs), and phylogenetic analysis revealed that the MdSUS genes were divided into three groups, named as SUS I, SUS II and SUS III, respectively. The SUS I and SUS III groups included four homologs each, whereas the SUS II group contained three homologs. SUS genes in the same group showed similar structural characteristics, such as exon number, size and length distribution. After assessing four different tissues, MdSUS1s and MdSUS2.1 showed the highest expression in fruit, whereas MdSUS2.2/2.3 and MdSUS3s exhibit the highest expression in shoot tips. Most MdSUSs showed decreased expression during fruit development, similar to SUS enzyme activity, but both MdSUS2.1 and MdSUS1.4 displayed opposite expression profiles. These results suggest that different MdSUS genes might play distinct roles in the sink-source sugar cycle and sugar utilization in apple sink tissues.     

Genome-wide analysis of the SCPL gene family in grape(Vitis vinifera L.)

Serine carboxypeptidase-like(SCPL) proteins are a group of acyltransferase enzymes that have important roles in plant growth, development, and stress responses. Although SCPL proteins have been studied in many plants, the biological functions of SCPL genes in grape are still unknown. In this study, 59 putative SCPL proteins were identified from the grape genome. A bioinformatics analysis, including chromosomal locations, exon/intron structures, phylogeny, ciselements, and conserved motifs, was performed for the gene family. The phylogenetic analysis revealed that VvSCPL proteins could be classified into three groups, with the gene motifs in each group showing high similarity levels. The number of exons in the VvSCPL genes ranged from 1 to 19, suggesting significant variations among grape SCPL genes. The expression of the VvSCPL genes, as assessed by RNA sequencing(RNA-seq) and quantitative real-time PCR, showed that most VvSCPL genes responded to drought-and waterlogging-stress treatments, which indicated their roles in abiotic stress responses. The results provide useful information for further study of SCPL genes in grape.     

水稻与拟南芥全基因组丝氨酸羧肽酶类蛋白家族比较分析(英文)

    基于水稻与拟南芥全基因组序列,在基因组与蛋白质组水平上对这2种模式植物的丝氨酸羧肽酶 (SCPs)基因家族进行比较分析.利用隐马可夫模型(hidden Markov models,HMM),发现水稻与拟南芥中分别存在71个与54个丝氨酸羧肽酶类(serine carboxypeptidases like,SCPL)蛋白编码基因,它们广泛分布于基因组中各条染色体上,并且存在多个基因簇聚区.基因结构分析显示,拟南芥的SCPL基因存在广泛的交替剪接方式,而这种现象在水稻SCPL基因中却不常见.蛋白结构分析表明,所有SCPL家族成员均具有α/β水解酶折叠亚族与S10家族典型的保守结构域与二级结构特征.系统进化分析表明,这125个SCPL蛋白可以分成3大类,与水稻不同,大多数拟南芥SCPL (88.9%)可归属于双链羧肽酶Ⅰ或Ⅱ.     

苦荞WOX家族全基因组鉴定及响应愈伤诱导率表达分析

【目的】全基因组鉴定苦荞WOX（WUSCHEL-related homeobox）基因,揭示其基因家族成员序列特征、基因表达模式及与出愈率的相关性,为突破苦荞再生及遗传转化难题提供理论基础。【方法】基于同源性搜索策略,以拟南芥WOX基因蛋白为参考序列,进行苦荞全基因组比对,获得苦荞WOX基因家族成员蛋白及核酸序列。基于蛋白同源性及保守结构域分析,鉴定出苦荞WOX基因家族所有成员。同时使用TBtools软件展示FtWOXs家族成员基因结构、保守结构域及启动子顺式作用元件特征。比较分析WOX基因家族成员在苦荞与拟南芥之间的基因组共线性。基于邻近法,利用MEGA X软件构建苦荞、拟南芥和水稻WOX基因家族成员蛋白序列系统进化树。以MS+2,4-D 3.0 mg·L^-1+6-BA 1.0 mg·L^-1为愈伤诱导培养基,下胚轴为外植体,选取70份苦荞品种诱导愈伤组织,评价不同基因型的出愈率。qRT-PCR比较分析高、低出愈率苦荞品种间FtWOXs基因表达水平。基于Pearson相关系数分析出愈率与FtWOXs基因家族成员表达相关性。【结果】共鉴定出30个苦荞WOX基因成员,在苦荞8条染色体上呈现不均匀分布。系统进化树表明30个苦荞WOX基因可划分为3大类,不同类群中WOX基因包含不同的保守结构域,主要的保守结构域为HD（Homeodomain）、START和MEKHLA结构域。保守基序分析表明,FtWOXs基因家族成员所含保守基序数目的范围为2—10个。基因结构分析表明,FtWOXs基因家族成员所含外显子数目的范围为2—18个。顺式作用元件分析表明FtWOXs基因启动子富含26个不同种类的顺式作用元件。系统进化分析表明,30个苦荞、15个拟南芥和12个水稻WOX基因家族成员可分为3类,其中第3类为苦荞独有。基因组共线性分析表明,6个WOX基因在苦荞和拟南芥之间存在基因组共线性。表达模式及相关性表明,FtWOX1/FtWOX12/FtWOX22/FtWOX23/FtWOX24与苦荞出愈率存在正相关性。【结论】苦荞FtWOXs成员存在丰富的序列变异特征,不同苦荞基因型中WOX基因表达水平及出愈率存在明显差异和一定的相关性,揭示不同苦荞WOX基因具有潜在的功能多样性。     

Identification and Bioinformatics Analysis of SnRK2 and CIPK Family Genes in Sorghum

Through bioinformatic data mining, 10 SnRK2 and 31 CIPK genes were identified from sorghum genome. They are unevenly distributed in the sorghum chromosomes. Most SnRK2 genes have 8 introns, while the CIPK genes have a few （no intron or less than 3 introns） or more than I0 introns. Phylogenetic analysis revealed that SnRK2 genes belong to one cluster and CIPK genes form the other independent cluster. The sorghum SnRK2s are subgrouped into three parts, and CIPK into five parts. More than half SnRK2 and CIPK genes present in homologous pairs, suggesting gene duplication may be due to the amplification of SnRK family genes. The kinase domains of SnRK2 family are highly conserved with 88.40% identity, but those of the CIPK family are less conserved with 63.72% identity. And the identity of sorghum CBLinteracting NAF domains of CIPKs is 61.66%. What＇s more, regarding to the sorghum SnRK2 and CIPK kinases, they are characterized with distinct motifs and their subcellular localization is not necessarily the same, which suggests they may be divergent in functions. Due to less conserved sequences, complex subcellular localization, and more family members, sorghum CIPK genes may play more flexible and multiple biological functions. According to the phylogenetic analysis of SnRK genes and SnRK functional studies in other plants, it is speculated that sorghum SnRK2 and CIPK genes may play important roles in stress response, growth and development.     

玉米Glyco-hydro-16糖苷酶家族全基因组的鉴定及其遗传分化

【目的】全基因组水平鉴定玉米Glyco-hydro-16家族,分析该家族基因在不同组织中的表达模式以及在不同玉米杂种优势群中的遗传分化。【方法】根据Glyco-hydro-16家族相对保守的序列及结构域,构建Glyco-hydro-16家族的隐马尔科夫模型文件（Glyco-hydro-16.hmm）,利用hmmersearch程序在玉米全基因组中进行比对,获得玉米中含有该家族保守结构域的所有序列。通过Blast2GO进行功能注释,利用蛋白质序列构建该家族的系统发育进化树。使用玉米自交系B73不同组织及不同发育时期的RNA-seq数据库分析该家族基因的表达模式。根据该家族基因在染色体上的位置筛选SNP标记,计算其在不同玉米杂种优势群间的群间遗传分化系数（genetic differentiation coefficient,Fst）,分析其遗传分化。【结果】根据该家族相对保守的序列及结构域,在全基因组水平共鉴定出34个玉米Glyco-hydro-16家族成员,注释表明所有基因都是木葡聚糖转移酶/水解酶基因,3个保守性较高的Motif区段存在于该家族所有成员中。通过系统发育关系和序列相似性将该家族分为8个亚家族,每个亚家族有2-8个基因,分布在除第3和第6染色体外的其他8条染色体上,在第2、第5及第10染色体上成簇分布。该家族在禾本科作物中同源性较高,与拟南芥分属不同的分支,但只有3个玉米成员（AC210669.3、GRMZM2G413006和GRMZM2G166944）被划分到禾本科分支中,其他玉米成员被划分到单独的分支中。通过表达谱分析表明该家族成员在玉米中均有表达,但在不同组织中的表达水平有差异。为解析该家族基因在不同玉米种质资源中等位基因的变异,根据玉米Glyco-hydro-16家族基因在染色体上的位置筛选SNP标记,计算其在玉米杂种优势群SS及NSS间的群间遗传分化系数。结果显示,共有10个该家族基因所处位点的Fst值高于阈值0.15,达到高度分化水平,分别位于第1、第2、第4、第5、第7以及第9染色体上。其中,位于第2染色体上的GRMZM2G091118相应位点的Fst值为0.52,表明该位点在SS群和NSS群间的群间遗传分化度极大。【结论】通过全基因组扫描在玉米中鉴定出34个Glyco-hydro-16家族成员,均为木葡聚糖转移酶/水解酶基因,在不同组织中,其表达模式不同,可能参与不同生理发育过程。部分该家族成员所处位点在玉米杂种优势群SS和NSS间的等位基因分化极大。     

Genome-wide identification and analysis of the regulation wheat DnaJ family genes following wheat yellow mosaic virus infection

The co-chaperone DnaJ plays an important role in protein folding and regulation of various physiological activities, and participates in several pathological processes. DnaJ has been extensively studied in many species including humans, drosophila, mushrooms, tomatoes, and Arabidopsis. However, few studies have examined the role of DnaJ in wheat (Triticum aestivum), and the interaction mechanism between TaDnaJs and plant viruses. Here, we identified 236 TaDnaJs and performed a comprehensive genome-wide analysis of conserved domains, gene structure and protein motifs, chromosomal positions and duplication relationships, and cis-acting elements. We grouped these TaDnaJs according to their domains, and randomly selected six genes from the groups for tissue-specific analysis, and expression profiles analysis under hormone stress, and 17 genes for plant virus infection stress. In qRT-PCR, we found that among the 17 TaDnaJ genes tested, 16 genes were up-regulated after wheat yellow mosaic virus (WYMV) infection, indicating that the TaDnaJ family is involved in plant defense response. Subsequent yeast two-hybrid assays verified the WYMV NIa, NIb and 7KD proteins interacted with TaDJC (TraesCS7A02G506000), which had the most significant changes in gene expression levels after WYMV infection. Insights into the molecular mechanisms of TaDnaJ-mediated stress tolerance and sensitivity could inform different strategies designed to improve crop resistance to abiotic and biotic stress. This study provides a basis for future investigation of the TaDnaJ family and plant defense mechanisms.     

大麦TIFY基因家族成员鉴定及表达分析

【目的】对大麦TIFY基因家族成员进行鉴定及表达分析,为进一步探究TIFY基因家族在大麦生长发育与胁迫响应中的作用机理打下基础。【方法】基于TIFY家族蛋白的保守域特征,利用HMMER从大麦中鉴定TIFY基因家族成员,利用采用生物信息学软件对其理化性质、保守基序、特征结构域、顺式作用元件、基因结构、系统进化及表达模式进行预测分析。【结果】从大麦中鉴定出15个HvTIFYs基因（HvTIFY1～HvTIFY15）,分布于5条染色体上,且大多数基因在染色体上成簇分布。15个HvTIFYs蛋白均具有TIFY家族蛋白的特征结构域（TIFY）,根据所含保守结构域的不同,可分为ZML（4个）和JAZ亚族（11个）,且亲水性蛋白（14个）和偏碱性蛋白（11个）居多,但均定位于细胞核;二级结构相似度较高,均由α-螺旋、β-转角和无规则卷曲组成,除HvTIFY7蛋白外,其余蛋白二级结构所占比排序:无规则卷曲>α-螺旋>β-转角。HvTIFYs基因结构存在明显差异,其中,JAZ亚族11个基因的内含子数为0~6; ZML亚族4个基因的内含子数为6～7个,系统发育进化树上相邻分支的基因具有较相似的基因结构。HvTIFYs基因启动子区域富含光、激素和胁迫等顺式作用元件,种类及分布均呈多样性。5个物种的79条TIFY蛋白分为4个组,恰好与TIFY家族的4个亚族对应,其中,ZML、TIFY和JAZ亚族包含单、双子叶植物的TIFY蛋白,而PPD亚族仅含有双子叶植物的TIFY蛋白。15个HvTIFYs基因在不同组织器官中的表达量存在明显差异,其中HvTIFY1、HvTIFY2和HvTIFY8基因在8个组织中的表达量均较高,HvTIFY10和HvTIFY15基因表达量中等,HvTIFY6基因表达量较低; HvTIFY11基因不表达。15个基因在根的不同组织中对盐胁迫的敏感程度不同。【结论】从大麦中鉴定出的15个HvTIFYs基因存在一定的功能分化,具有明显的组织和时空特异性,推测其在大麦逆境响应和激素调节中具有重要调控作用。     

甜瓜持绿蛋白基因家族的全基因组鉴定及进化分析

持绿蛋白在调节植物叶绿素降解和衰老过程中起到非常重要的作用,利用公布的甜瓜基因组数据,使用生物信息学方法对甜瓜全基因组SGR基因的结构、系统进化关系、保守基序及表达谱进行分析。结果表明：甜瓜中共有4个SGR类型基因,命名为CmSGR01~CmSGR04,其蛋白质在167~257 aa之间,通过系统进化树分析,发现甜瓜与黄瓜属同一科,它们的SGR聚在一起,说明相对其他物种,二者的SGR蛋白在其他物种分化后进化较小;MEME软件分析发现了SGR因含有5个保守的基序。通过甜瓜SGRs基因家族的系统分析,为进一步阐明甜瓜中SGR蛋白结构及功能提供理论基础和有价值的资料。