A repressor element in the 5'-untranslated region of human Pax5 exon 1A

Five members of the RecQ helicase family, RECQL, WRN, BLM, RTS and RECQL5, have been found in human and three of them (WRN, BLM and RTS) were disclosed to be the genes responsible for Werner, Bloom and Rothmund–Thomson syndromes, respectively. RECQL5 (RecQ helicase protein-like 5) was isolated as the fifth member of the family in humans through a search of homologous expressed sequence tags. The gene is expressed with at least three alternative splicing products, , β and γ. Here, we isolated mouse RECQL5β and determined the DNA sequence of full-length cDNA as well as the genome organization and chromosome locus. The mouse RECQL5β gene consists of 2949 bp coding 982 amino acid residues. Comparison of amino acid sequence among human (Homo sapiens), mouse (Mus musculus), Drosophila melanogaster and Caenorhabditis elegans RECQL5β homologs revealed three portions of highly conserved regions in addition to the helicase domain. Nineteen exons are dispersed over 40 kbp in the genome and all of the acceptor and donor sites for the splicing of each exon conform to the GT/AG rule. The gene is localized to the mouse chromosome 11E2, which has a syntenic relation to human 17q25.2-q25.3 where human RECQL5β exists. Our genetic characterizations of the mouse RECQL5β gene will contribute to functional studies on the RECQL5β products.     

金针菇淀粉酶家族基因鉴定及其表达特性分析

本研究对金针菇淀粉酶家族基因进行了信息分析,并选用金针菇双核菌株H1123作为实验材料,分析了菌丝生长过程中淀粉酶活性和淀粉酶基因表达特性之间的关系。结果表明,金针菇淀粉酶家族包含6个α淀粉酶和1个γ淀粉酶。7个淀粉酶基因的表达量均在菌丝接种后第10天出现峰值,并与胞外淀粉酶活性呈同步变化,说明基质中淀粉的分解和利用是淀粉酶家族各成员之间相互协调的结果。其中α-Amy-1、α-Amy-4、α-Amy-5的上调幅度最大,为淀粉降解和代谢过程的主效基因。值得注意的是胞内淀粉酶基因α-Amy-1在第10天时达到约90倍的上调表达水平。我们推测：金针菇胞外淀粉酶将淀粉分解为小分子单糖的同时,其胞内淀粉酶也参与了这些糖类的吸收和运输过程。     

Identification, sequence and developmental expression of invertebrate flotillins from Drosophila melanogaster

Caveolae are vesicular organelles that represent a sub-compartment of the plasma membrane. Caveolins (Cav-1, -2 and -3) and flotillins {FLO-1 and FLO-2 [also known as epidermal surface antigens (ESAs)]} are two families of mammalian caveolae-associated integral membrane proteins. Although a caveolin gene family has recently been described in the invertebrate Caenorhabditis elegans, it remains unknown as to whether flotillin homologues exist in invertebrates.

Here, we report the identification, cDNA sequence and embryonic expression pattern of the first invertebrate flotillin, i.e. flotillin from Drosophila melanogaster (FLO^Dm). FLO^Dm is most closely related to mammalian flotillin-1. Remarkably, the invertebrate FLO^Dm protein behaves like mammalian flotillins and is targeted to the caveolae-enriched membrane fraction after transient expression in mammalian cells. Localization of the FLO^Dm message in D. melanogaster embryos reveals that expression of FLO^Dm is confined primarily to the developing nervous system. This is consistent with our previous observation that mammalian flotillin-1 mRNA and protein is expressed abundantly in brain tissue. Interestingly, the FLO^Dm gene is localized to chromosomal region 52 B1–B2. In addition, we find that at least two flotillin-related genes are expressed in D. melanogaster. Our current results provide a starting point and systematic basis for dissecting the role of flotillin in caveolae and neuronal development using Drosophila as a genetic system.     

The expression pattern of a mouse doublesex-related gene is consistent with a role in gonadal differentiation

The signal for somatic sex determination in mammals, Caenorhabditis elegans and Drosophila melanogaster is chromosomal, but the overall mechanisms do not appear to be conserved between the phyla. However it has been found quite recently that the C. elegans sex-determining gene Mab-3 contains a domain highly homologous to the Drosophila sex-determining gene doublesex (dsx) and shares a similar role. These data suggest that at least some aspects of the regulation of sex determination might be conserved. In humans, a doublesex-related gene (DMRT1) was identified at less than 30 kb from the critical region for sex reversal on chromosome 9p24 (TD9). In order to get insights into the role of DMRT1 in sex determination/differentiation, we have isolated DMRT1 mouse homologue (Dmrt1) and analysed its expression pattern. The gene is expressed in the genital ridges of both sexes during the sex-determining switch and it shows male/female dimorphism at late stages of sex differentiation.     

The sex-peptide gene (Acp70A) is duplicated in Drosophila subobscura

A 3.1-kb region of Drosophila subobscura homologous to the Acp70A region of D. melanogaster, which contains the sex-peptide gene, was cloned and sequenced. This region contains an approximately 600-bp duplication that includes the sex-peptide and its 5′ and 3′ flanking regions. The preproteins are 54 and 56 amino acids long, respectively (as compared to 55 amino acids in D. melanogaster), and each includes a 19-amino-acid-long signal peptide. The C-terminal part of the mature peptide is highly conserved between D. melanogaster and the two copies of D. subobscura. In this species, both copies of the gene are transcribed and, like in D. melanogaster, only expressed in males. The duplicated region includes 300 bp upstream of the gene that would therefore seem sufficient for their expression in males. This region presents at its 5′ end a stretch 93-bp that has a high similarity with the corresponding region of D. melanogaster and could be part of a still unidentified regulatory element of these genes.     

The influence of heavy water (D2O) on the thermopreferendum in Drosophila melanogaster

1. 1. Thermopreferendum of contron Drosophila melanogaster flies, fed sugared water was compared with that of flies, fed sugared water containing 50% D₂O.

2. 2. Deuterium oxide increased not only the thermoresistance of some proteins, cells and the organisms, but also organism thermophilly.

植物多基因干扰载体体系构建与效用分析

多数重要的功能基因属于多基因家族,这些家族成员间存在功能冗余,高效的多基因干扰体系对研究多基因家族成员的生物学功能及其分子调控机制具有重要意义。对pCAMBIA1301载体改造,构建了适用于植物的多基因干扰体系pCAMBIA1301m和pCAMBIA1301s。使用该多基因干扰体系构建了四基因的干扰载体pCAMBIA1301m：35S∷SlPP2C1-2-3-4,4个目标基因为来源于番茄PP2C家族A组的PP2C1、PP2C2、PP2C3和PP2C4,并通过遗传转化导入番茄,用GUS染色和PCR检测转基因阳性植株,再利用RT-qPCR技术检测T₁和T₂代转基因植株中目标基因的干扰效率,用T₂代种子分析转基因番茄对ABA敏感性。结果表明,应用该干扰体系成功获得了四基因干扰的转基因植株35S∷SlPP2C1-2-3-4。在转基因番茄中4个目标基因的表达量显著低于野生型,其干扰效率均高于70%,转基因番茄种子萌发具有强烈的ABA不敏感性。多基因干扰体系能高效地同时沉默多个目标基因。     

Acetaldehyde detoxification mechanisms in Drosophila melanogaster adults involving aldehyde dehydrogenase (ALDH) and alcohol dehydrogenase (ADH) enzymes

The mechanism of acetaldehyde detoxification in Drosophila melanogaster adults has been studied by comparing physiological in vitro and in vivo data. ADH⁺ and ADH⁻ flies, both lacking aldehyde dehydrogenase activity from ADH (ALDH^ADH, ALDH (ALDH) or both enzymes were exposed to acetaldehyde or ethanol, and the toxicity and internal accumulation of both compounds were determined. Acetaldehyde was extremely lethal for flies whose ALDH activity had been inhibited by cyanamide, though acetaldehyde was effectively detoxified by flies whose ALDH^ADH activity had been inhibited by acetone. After exposure to acetaldehyde, both acetaldehyde and ethanol rapidly accumulated in flies lacking ALDH activity, but not in flies lacking ALDH^ADH activity. However, ethanol but not acetaldehyde quickly accumulated in flies lacking ALDH activity after exposure to ethanol. Our results provide in vivo evidence that, as opposed to larvae, in D. melanogaster adults acetaldehyde is mainly oxidized into acetate by means of ALDH enzymes. However, the reducing activity of the ADH enzyme, which transforms acetaldehyde into ethanol, also plays an essential role in the detoxification of acetaldehyde. Differences in ALDH activity might be important to explain the differences in ethanol tolerance found in natural populations.     

桃ERF转录因子家族生物信息学分析及 芽萌发相关基因筛选

以中油四号油桃(Prunus persica var. nectarina)为研究对象, 利用MEGA 6.0、MEME、GSDS和DNAMAN 6.0等软件对桃ERF家族数据进行生物信息学分析, 鉴定得到102个ERF转录因子家族基因, 并通过构建系统进化树将这102个基因分为10个子家族(I-X)。基因结构分析表明, 有81个基因不含内含子, 20个基因含有1个内含子, 有1个基因与其它成员差异较大, 含有5个内含子。保守元件分析表明, ERF家族包含20个保守元件, 其中Motif 1、Motif 2和Motif 4都属于AP2/ERF结构域, 同一个保守元件主要出现在同一个子家族中, 并且大部分保守元件的功能未知。VIII子家族基因的荧光定量PCR分析表明, 在桃叶芽处于不同的发育状态时, PpeERF068的表达量存在较大差异, 光照培养箱中培养的桃芽在萌发过程中各时期表达量变化趋势进一步表明该基因可能与叶芽萌发有关, 将其命名为PpeEBB1。该研究为进一步揭示PpeEBB1的分子机制奠定了基础, 并为桃树的栽培管理和熟期调控了提供理论指导。     

决明GRAS基因家族全基因组鉴定及其在盐和干旱胁迫条件下的表达分析

目的: 基于决明(Senna tora L.)全基因组数据,对GRAS家族成员、理化性质、基因结构、进化关系以及胁迫条件下的表达模式进行鉴定和分析。方法: 将决明基因组蛋白数据与拟南芥GRAS成员进行比对,分别利用TBtools、MEGA-X、CLUSTALW、MEME等生物信息学软件和工具,对决明GRAS基因家族成员进行分析。利用qRT-PCR(quantitative real-time PCR)检测干旱和盐胁迫条件下决明根中GRAS基因的表达情况。结果: 50个StGRAS分为9个亚家族,不均等地分布在13条染色体上。结构分析表明,StGRAS34和StGRAS12分别与蒺藜苜蓿(Medicago truncatula)结瘤信号蛋白NSP1和NSP2高度同源。StGRAS的启动子区域多含有与胁迫响应、激素调节等相关的响应元件。qRT-PCR结果表明,在盐胁迫条件下,StGRAS表达具有明显差异;在干旱胁迫条件下,绝大多数检测基因能够快速响应,表达显著升高;两种胁迫条件下,StGRAS28和StGRAS29表达趋势互补,具有协同调控关系。结论: GRAS基因家族能够广泛参与胁迫响应,其中StGRAS28与StGRAS29可能共同参与介导决明根的盐与干旱胁迫应答,StGRAS34和StGRAS12分别作为决明共生结瘤的NSP1和NSP2,可能与增强结瘤因子信号诱导相关,这为进一步挖掘和研究GRAS基因在决明响应胁迫和共生固氮过程所发挥的作用提供了基础。     

Spatially and temporally-restricted expression of two T-box genes during zebrafish embryogenesis

T-box genes are conserved in all animal species. We have identified two members of the T-box gene family from the zebrafish, Danio rerio. Zf-tbr1 and zf-tbx3 share high amino acid identity with human, murine, chick and Xenopus orthologs and are expressed in specific regions during zebrafish development.     

Relationships of Drosophila melanogaster RECQ5/QE to cell-cycle progression and DNA damage

Members of the RecQ family of DNA helicases are involved in the cellular response to DNA damage and are regulated in the cell-cycle. However, little is known about RecQ5, one of these members. The level of RECQ5/QE, Drosophila melanogaster RecQ5, was increased after the exposure of cultured cells to methyl-methanesulfonate. Transgenic flies that overexpressed RECQ5/QE in their developing eye primordia showed mild roughening of the ommatidial lattice. DNA-damaging agents and the mei-41 mutation enhanced the phenotype caused by RECQ5/QE overexpression. Overexpression of RECQ5/QE perturbed the progression of the cell-cycle in response to DNA damage in the eye imaginal discs. These results suggest that RECQ5/QE interacts with components of the cell-cycle during its progression in response to DNA damage.     

水稻非生物胁迫响应基因OsMIP1的表达与进化分析

MID1编码R-R型的MYB转录因子,对不同的非生物胁迫均有响应,特别是在水稻(Oryza sativa)生殖期会受到干旱胁迫的诱导,进而在一定程度上可以保持花粉的育性并稳定水稻产量。为进一步研究水稻MID1对非生物胁迫的响应网络,利用酵母双杂交系统筛选出与其互作的蛋白因子OsMIP1,并利用双分子荧光互补系统在本氏烟草(Nicotiana benthamiana)细胞中得到验证。结果表明,OsMIP1编码1个预测含有ENTH/ANTH/VHS结构域的跨膜转运蛋白。OsMIP1在根、茎、叶、小穗和胚乳中均有表达。干旱胁迫下,OsMIP1在叶片和生殖器官中表达,特别是在减数分裂后的小花中表达显著上调。这些结果暗示,OsMIP1在花器官抵抗干旱胁迫中起一定的作用。在水稻营养生长阶段,OsMIP1表达还受到包括Na Cl和甘露醇在内的其它非生物胁迫的影响,暗示其可能在其它非生物胁迫调节中也具有一定的作用。植物中关于编码ENTH/ANTH/VHS结构域蛋白的研究很少。通过对MIP1亚家族进化关系进行分析,结果表明,在被子植物中,MIP1可分为6大类,这6大类分别来自被子植物祖先中原本就存在的6个拷贝,在被子植物的进化过程中又经历了多次基因重复和拷贝丢失等事件。MIP1家族成员广泛分布于被子植物中并可能具有抗胁迫等功能。     

麦洼牦牛不同生长阶段肝脏差异表达基因分析

为探讨牦牛肝脏生长过程中基因的表达特征,采用Illumina高通量测序平台(HiSeqTM2500)对1日龄组(LD)、15月龄组(LM)和5岁龄组(LY)的健康麦洼牦牛肝脏进行转录组测序,并以qRT-PCR验证差异表达基因(differentially expressed genes,DEGs)的表达量.结果 显示,...     

Gene within gene configuration and expression of the Drosophila melanogaster genes lethal(2)neighbour of tid [l(2)not] and lethal(2)relative of tid [l(2)rot]

In this paper, we describe the structure and temporal expression pattern of the Drosophila melanogaster genes l(2)not and l(2)rot located at locus 59F5 vis à vis the tumor suppressor gene l(2)tid described previously and exhibiting a gene within gene configuration. The l(2)not protein coding region, 1530 nt, is divided into two exons by an intron, 2645 nt, harboring the genes l(2)rot, co-transcribed from the same DNA strand, and l(2)tid, co-transcribed from the opposite DNA strand, located vis à vis. To determine proteins encoded by the genes described in this study polyclonal rabbit antibodies (Ab), anti-Not and anti-Rot, were generated. Immunostaining of developmental Western blots with the anti-Not Ab resulted in the identification of a 45-kDa protein, Not45, which is smaller than the Not56 protein predicted from the sequence. Its localization in endoplasmic reticulum (ER) was established by immunoelectron microscopy of Drosophila melanogaster Schneider 2 cells. Not45 shows significant homology to yeast ALG3 protein acting as a dolichol mannosyltransferase in the asparagine-linked glycosylation. It is synthesized ubiquitously throughout embryonic life. The protein predicted from the l(2)rot sequence, Rot57, shows a homology to the NS2B protein of the yellow fever virus1 (yefv1). The results of l(2)rot RNA analysis by developmental Northern blot and by in situ RNA localization, as well as the results of the protein analysis via Western blot and immunohistochemistry suggest that l(2)rot is transcribed but not translated. Since RNAs encoded by the genes l(2)tid and l(2)rot are complementary and l(2)rot is presumably not translated we performed preliminary experiments on the function of the l(2)rot RNA as a natural antisense RNA (asRNA) regulator of l(2)tid expression, expressed in the same temporal and spatial manner as the l(2)tid− and l(2)not RNA. l(2)tid knock-out by antisense RNA yielded late embryonic lethality resulting from multiple morphogenetic defects.