Determination of Amylose Content and Its Relationship with RVA Profile Within Genetically Similar Cultivars of Rice(Oryza sativa L.ssp.japonica)

Anther culture pure lines with antisense Wx gene were generated by Agrobacterium tumefaciens-mediated co-transformation followed by anther culture in transgenic rice （Oryza sativa L. ssp. japonica）. The antisense Wx transgenic pure lines were used to analyze the differences and the relationship between RVA eigenvalues among the lines with different amylose contents. 77 pure lines of anther culture having antisense Wx gene were studied for the amylose content of its offspring cultivar, Wuyunjing 7. It was found that levels ofamylose content were similar to the control in 19 lines （16.0%）; 1-5% lower than control in 50 lines, of which, within 11.0-13.9% in 40 lines; and 3.1-4.0% in 8 lines. The effect of the amylose content on RVA eigenvalue was analyzed through the RVA profile graphic comparison and test of significance for RVA eigenvalues. The analysis of RVA profiles with different amylose contents indicated that there were two kinds of RVA profiles within genetically similar cultivars. The lines with 3.1-4.0% of amylose content were distinctly different from other lines and conventional glutinous rice. The comparison of the similarity curve of RVA profile of the lines with different amylose contents showed that the lines with lower amylose content had a distinguished RVA profile with the curve increasing gradually, but not exceeding the first apex. The test of significance for eigenvalues of the RVA profile in the lines with different amylose contents indicated that there were five eigenvalues remarkably different among the lines with 3.1-4.0% of amylose content compared with other two groups. Further, there were three eigenvalues remarkably different among the lines with 11.0-13.5% of amylose content compared with control group. An optimized mathematical model, which characterizes the relationships between the amylose content and RVA eigenvalue, has been established in this study. From this model, it was clearly indicated that the parameters PeT and SBV were more related to amylose content. It was concluded that the differences in amylose content not only affected the eigenvalues of RVA but also caused different RVA profiles within genetically similar cultivars. The introduction of antisense Wx gene could lead to reduce the amylose content and lay theoretical foundation for quality improvement in rice breeding programs.

Development of Simple Functional Markers for Low Glutelin Content Gene 1 (Lgc1) in Rice (Oryza sativa)

Rice with low glutelin content is suitable as functional food for patients affected by kidney failure. Low glutelincontent gene Lgc1 in rice has a 3.5-kb deletion between two highly similar glutelin genes GluB4 and GluB5, which locates on the short arm of chromosome 2. To improve the selection efficiency in low glutelin-content rice breeding, two molecular markers designated as InDel-Lgc1-1 and InDel-Lgc1-2 were developed to detect the low glutelin-content gene Lgc1. A double PCR detection indicated that combined use of the two markers could easily distinguish the genotypes of Lgc1 from different rice varieties. Therefore, as a simple and low-cost technique, the molecular marker could be widely used to identify different varieties with Lgc1 gene and applied in marker-assisted selection of low glutelin-content rice.

Relationship Between Single Nucleotide Polymorphism of Glycogen Synthase Gene of Pacific Oyster Crassostrea gigas and Its Glycogen Content

Glycogen is important not only for the energy supplementary of oysters, but also for human consumption. High glycogen content can improve the stress survival of oyster. A key enzyme in glycogenesis is glycogen synthase that is encoded by glycogen synthase gene GYS. In this study, the relationship between single nucleotide polymorphisms(SNPs) in coding regions of Crassostrea gigas GYS(Cg-GYS) and individual glycogen content was investigated with 321 individuals from five full-sib families. Single-strand conformation polymorphism(SSCP) procedure was combined with sequencing to confirm individual SNP genotypes of Cg-GYS. Least-square analysis of variance was performed to assess the relationship of variation in glycogen content of C. gigas with single SNP genotype and SNP haplotype. As a consequence, six SNPs were found in coding regions to be significantly associated with glycogen content(P < 0.01), from which we constructed four main haplotypes due to linkage disequilibrium. Furthermore, the most effective haplotype H2(GAGGAT) had extremely significant relationship with high glycogen content(P < 0.0001). These findings revealed the potential influence of Cg-GYS polymorphism on the glycogen content and provided molecular biological information for the selective breeding of good quality traits of C. gigas.

Effects of RNAi Silencing of SSIII Gene on Phosphorus Content and Characteristics of Starch in Potato Tubers

The sense and antisense fragments of the soluble starch synthase （SSII1） gene and the intron fragment of somatic embryogenesis receptor-like kinase （SERK1） gene were cloned from potato using PCR techniques. The RNAi plant expression vectors pBI-SSIII-RNAi and pBIC-SSIII-RNAi were constructed which containing fusion fragment of ＂sense fragment-intron-antisense fragment＂ driven by the constitutive expression promoter CaMV 35S and the tuber-specific expression promoter CIPP, respectively. The putative transgenic plants of potato cultivars Kexin-1 and Kexin-4 were obtained using Agrobacterium-mediated transformation method. PCR assay showed that the interference fragment of SSlll gene was integrated into potato genome. The RT-PCR analysis showed that the expression of SSlll gene was repressed apparently on the transcription level. Starch granules of the transgenic potato plants were different in morphology and became cracked in starch granule centre compared with the non-transgenic control plants. The amylose content of starch was increased by 2.68-29.05%, amylopectin to amylose ratio of starch had declined significantly, and the phosphorus content of the starch of the transgenic plants was reduced 9.94-58.36% compared with control plants. The results could provide certain foundation for improvement of potato starch quality.

Characterization of TaCOMT genes associated with stem lignin content in common wheat and development of a gene-specific marker

Stem lignin content(SLC) in common wheat(Triticum aestivum L.) contributes to lodging resistance. Caffeic acid 3-O-methyltransferase(COMT) is a key enzyme involved in lignin biosynthesis. Characterization of TaCOMT genes and development of gene-specific markers could enable marker-assisted selection in wheat breeding. In the present study, the full-length genomic DNA(gDNA) sequences of TaCOMT genes located on chromosomes 3 A, 3 B, and 3 D were cloned by homologous cloning. Two allelic variants, TaCOMT-3 Ba and TaCOMT-3 Bb, were identified and differed by a 222-bp insertion/deletion(InDel) in the 3′-untranslated region(3′-UTR). A co-dominant gene-specific marker based on this InDel was developed and designated as Ta COMT-3 BM. A total of 157 wheat cultivars and advanced lines grown in four environments were used to validate the associations between allelic patterns and SLC. The SLC of cultivars with TaCOMT-3 Ba was significantly(P<0.01) higher than that of those with TaCOMT-3 Bb, and the marker TaCOMT-3 BM could be effectively used in wheat breeding.

Analysis of the Genetic Effects of Three Genes Involved in de novo Purine Biosynthesis on IMP Content in Baier Chickens

GPAT,AIRC and purH genes are involved in the de novo purine biosynthesis,and they all had significant effects on muscle inosine monophosphate(IMP) content in chickens.This study was designed to investigate the effects of GPAT,AIRC and purH genes on muscle IMP content in a relatively large population of Baier chickens;single genotype effects as well as the combined genotype effects were analyzed.The results further support that GPAT,AIRC and purH genes had effects on muscle IMP content;they might be candidate loci or linked to major genes affecting muscle IMP content.The combined genotypic effects were significantly higher than those of the single genotypes and were even larger when more gene loci were combined.We tentatively conclude that combined genotypes are superior to single genotypes as potential molecular markers for meat quality traits in chicken.

An Integrated Quantitative Trait Locus Map of Oil Content in Soybean,Glycine max(L.) Merr.,Generated Using a Meta-Analysis Method for Mining Genes

Soybean is a major cash crop in the world, and its oil content was one of the very important traits. Therefore, the study of gene mapping for oil content in soybean is very important for breeding application. At present, at least 130 QTL loci for soybean oil content have been published; however, the mapping results of oil content were dispersed and a coalescent public map should be established to integrate the published QTLs, and to more efficiently mine genes based on the meta- analysis method of the bioinformatics tools. This study was to construct an integrated map of QTLs for soybean oil content and accelerate the application of bioinformation resource related to oil content improvement in the practice of soybean breeding. We collected information of 130 QTLs reported over the past 20 yr for soybean oil content and used the Software BioMercator 2.1 to project QTLs from their own maps onto a reference map, which was an early-integrated map constructed by Song （2004） for oil-content quantitative trait loci （QTLs） in soybean. Gene mining was performed based on the meta-analysis by running the local ver. GENSCAN and InterProScan. The confidence interval of QTLs was efficaciously narrowed using the meta-analysis method, and 25 consensus QTLs were mapped on the reference map. Using a local version of GENSCAN, 12 805 sequences in the consensus QTL intervals were predicted. With BLAST, these predicted sequences were aligned to gene sequences from the International Protein Index database using InterProScan locally. Thirteen predicted genes were in the class of the geme ontology （GO） accession （0006631）, which were involved in the fatty acid metabolic process. These genes were analyzed using BLAST at the NCBI website to examine whether they were related to oil content. Six genes were found in the oil-synthesis pathway. Twenty-five consensus QTLs and six genes were found in the oil-synthesis pathway. These results would lay the foundation for marker-assisted selection and mapping QTL precisely, and these genes will facilitate the researches on the gene mining of oil synthesis and molecular breeding in soybean.

Genetic Analysis and Improvement Strategies of Protein Content in Rice Seeds

Enhancing the nutritional quality of food crops is a way to improve human nutrition and health. Grain protein content （ GPC ） is an important nutritional quality trait for rice and many other crops. Therefore, it will be very significant to increase GPC and improve rice quality. This paper mainly reviewed the genetic studies GPC in rice, mapping and cloning of QTLs and genes associated with GPC. However, little is known about the molecular mechanism and gene function related to GPC in rice. Thus, here we put forward the genetic strategy by gene pyramiding or molecular marker assisted selection to improve GPC and nutritional quality in rice. This review could provide important information for genetic improvement of grain nutritional quality of rice.

不同心皮数量棉花心皮发育特征、基因表达及相关性状比较

【目的】探究棉花心皮发育特征,不同心皮数量的差异表达基因与植物激素含量,以及心皮数量与棉铃发育的关系。【方法】以3心皮(C3)、4心皮(C4)、5心皮(C5)棉花材料为研究对象,观察棉花心皮发育过程,统计不同杂交组配后代的心皮数量。花芽发育5 d、10 d和开花当天分别进行转录组测序及激素含量测定,并在不同发育时期测定棉铃的表型。【结果】花蕾长度为2~3 mm时,心皮原基发育起始;花蕾长度为4~5 mm时,心皮融合形成合生心皮。心皮原基的发育早于雌蕊器官。C3、C4、C5两两杂交F1的平均心皮数量介于双亲之间。C3、C4和C5中差异表达基因主要富集于生物学过程。花芽发育5 d、10 d和开花当天,富集通路中心皮发育相关基因AP1、AGL6、WUS、MYB21和ARF6在C5中的表达量高于C4,且显著高于C3。花芽发育5 d、10 d,C5的茉莉酸含量显著高于C3、C4,吲哚乙酸含量显著低于C3、C4;C4的脱落酸含量显著低于C3、C5。开花后20 d、35 d和60 d,C5的棉铃直径、棉铃鲜物质质量、棉瓣厚度以及纤维和胚珠鲜物质质量显著高于C3、C4。【结论】3、4、5心皮棉花亲本的杂交组配后代中,心皮数量介于双亲之间。多个心皮发育相关基因在C5中的表达量更高。开花前,C5中茉莉酸含量最高,吲哚乙酸含量最低。心皮数量增多利于增加棉铃直径、鲜物质质量,同时增加纤维和胚珠鲜物质质量。

Effect of Indoor Concentrate Feeding vs. Outdoor Grazing on the Expression of Genes Involved in Muscle Growth and Nutrient Content in Japanese Black Steer Muscle

The objective of the present study was to investigate the effect of outdoor grazing on the expression of genes involved in muscle growth and the nutrient contents of skeletal muscle in steers. Ten Japanese Black steers were divided into two groups: grazing (GR) and concentrate (CT) groups. Crude protein, extractable lipid, moisture, fatty acid, cooking loss and Warner Bratzler shear force in muscle tissue were analyzed. The gene expression of myosin heavy chain (MyHC) isoform (2a, 2x and slow), myostatin, follistatin, peroxisome proliferator-activated receptor γ2 (PPARγ2), CCAAT/enhancer binding protein α (C/EBPα), heat shock protein (HSP) 27 and HSP40 in skeletal muscles was evaluated at the end of fattening. Decreases in MyHC-2a and MyHC-2x (fast-twitch fiber type) expression in the longissimus lumborum (LL) muscle were detected in the GR group compared with the CT group;in contrast, an increase in MyHC-slow (slow-twitch fiber type) expression was shown in the GR group. These results suggest that grazing initiated muscle fiber type conversion to slow-twitch from fast-twitch. A decrease in extractable lipid content was observed in the GR group in the LL and semitendinosus (ST) muscles. Crude protein content in the LL muscle in the GR group was higher than in the CT group. MyHC expression in LL muscle in the GR group was greater than in the CT group. A decrease in myostatin and PPARγ2 gene expression was detected in the GR group compared with the CT group in both muscles. Expression of C/EBPα in LL muscle in the GR group was lower than in the CT group. These results suggest that grazing steers at the end of fattening may lead to an increase in protein content and a decrease in fat accumulation in LL and/or ST muscles by regulation of myostatin, MyHC, PPARγ2 and C/EBPα gene expression.

大豆籽粒Ve含量的全基因组关联分析

维生素E(Ve)是大豆油中一种天然抗氧化剂,是评价大豆油营养价值的重要指标。本研究利用含有264份的大豆自然群体在2021年和2022年测定了籽粒中α-、γ-和δ-生育酚含量,并进行全基因组关联分析(Genome-wide association study,GWAS)。本研究共检测到199个与大豆Ve含量显著关联的SNP位点,其中9个可在2个环境或者2个性状被重复检测到,分别位于3号、7号、11号、12号、13号、15号、17号和18号染色体上。其中位于7号染色体上的显著关联信号是控制α-生育酚含量的主效位点,可在2年环境中被检测到,表型变异解释率为9.83%。对该位点候选基因进行筛选,获得一个编码myb转录因子的基因Glyma.07G054000,可能是这个位点的效应基因。另外,在12号染色体上得到2个编码γ-生育酚甲基转移酶的基因Glyma.12G014200和Glyma.12G014300,有可能是影响Ve含量的重要基因。本研究结果有助于解析大豆籽粒Ve含量的遗传基础及其调控机制,为大豆品质遗传改良奠定了基础。

糜子种质资源淀粉含量与Waxy基因等位变异分析

本研究测定了100份糜子种质资源的直链淀粉和支链淀粉含量,采用分子标记对胚乳直链淀粉合成调控基因Waxy进行基因分型,并选取不同直链淀粉含量代表种质资源进行基因测序和差异位点分析。结果表明,100份糜子种质资源直链淀粉含量变化幅度为0~22.78%,平均6.07%,直链淀粉含量低于3.7%的糯性材料占36%,完全糯性材料占24%;支链淀粉含量变化幅度为4.55%~56.73%,平均15.30%。分子标记M5/R11扩增产物能有效区分S_(0)、S_(-15)和S_(0)S_(-15)基因型;标记int5Lf/R3和M12/R12的PCR产物利用内切酶ACC I和Eco N I剪切,可鉴别出L_(C)、L_(Y)、L_(F)基因型。100份糜子种质共发现9种基因型,其中S_(0)/L_(c)数量最多,占33%,S_(-15)/L_(F)占25%,杂合型S_(0)S_(-15)/L_(F)、S_(0)S_(-15)/L_(C)、S_(0)S_(-15)/L_(Y)L_(F)各占2%。通过Waxy基因序列比对,在地方品种甘谷黑蝉背、黑糜子、庆阳饿死牛,育成品种晋黍9号、赤糜2号等种质资源中发现了大量新的SNPs位点,可用于基因功能和糜子育种材料创制研究。本研究结果为糜子分子育种工作及品质改良提供了理论依据。

五指毛桃不同部位补骨脂素合成酶基因的表达及其代谢产物含量

为探究五指毛桃(Ficus hirta Vahl)不同部位补骨脂素合成酶基因(psoralen synthetase,PS)表达与补骨脂素含量的关系,本研究分别采用实时荧光定量PCR法和高效液相色谱法测定来自广西和福建的五指毛桃根、茎、叶和果实PS基因的表达量及补骨脂素含量,分析不同五指毛桃种质不同部位PS基因表达及其代谢产物含量的差异。结果显示:PS基因在广西和福建五指毛桃的根、茎、叶和果实中均有表达,且其表达量具有组织特异性,在根中的相对表达量最高(侧根高于主根),叶中次之(全缘叶高于缺刻叶),茎和果实的表达量极低。使用高效液相色谱测得广西和福建的五指毛桃中补骨脂素含量存在差异,在2个五指毛桃种质的主根、侧根、缺刻叶、全缘叶、茎、果实中均有积累,侧根中的含量最高,分别为3.206、2.947 mg/g,主根次之(2.136、0.419 mg/g),缺刻叶中的含量分别为0.022、0.028 mg/g,全缘叶中的含量分别为0.069、0.035 mg/g,茎(0.003、0.003 mg/g)和果实(0.002、0.001 mg/g)中含量较低。五指毛桃PS基因表达与补骨脂素含量具有相关性,该研究结果为解析PS基因在五指毛桃补骨脂素合成中的作用提供参考。

Relationship Between the First Base of the Donor Splice Site of Waxy Gene Intron 1 and Amylose Content in Yunnan Indigenous Rice Varieties

There exists a single nucleotide polymorphism, G or T, at the first base of the donor splice site of waxy gene intron 1 in rice. In order to study the relationship between the first base of the donor splice site of waxy gene intron 1 and amylose content in rice, the one-step PCR method was used to determine whether it is G or T in 220 Yunnan indigenous rice varieties from 14 districts, 55 towns/counties of Yunnan Province, and 101 varieties of which were validated by the PCR-Acc I method. According to the G/T polymorphism, 164 rice varieties showed GG-genotype, while the other 56 fell into TT- genotype, accounting for 74.5% and 25.5% of all the test varieties, respectively. When all the rice varieties were divided into indica and japonica subspecies, it was found that 80.5% of indica rice and 67.0% of japonica rice belonged to GG-genotype. The rice varieties with GG-genotype had significantly higher amylose content （18.95% on average） than those with TT- genotype （all below 16%）, but 33 rice varieties with GG-genotype still had low amylose content ranging from 3.91% to 15.93%, and most of them came from the Dai minority area in the Southwest of Yunnan Province. However, there was no significant difference in the mean amylose content of the same GG or TT genotypes between indica and japonica rice, suggesting that different genetic backgrounds, indica or japonica, had no effect on amylose content. The coefficient of correlation between the genotype and amylose content was 0.733 （P〈0.01）.

大豆地方种质资源鲜籽粒可溶性糖含量的全基因组关联分析

【目的】可溶性糖含量是鲜食大豆重要的品质性状之一,研究大豆鲜籽粒可溶性糖含量的遗传变异,深入解析可溶性糖含量的遗传机制,为鲜食大豆种质创新及品质育种提供依据。【方法】利用来自东北大豆生态区、北方大豆生态区、黄淮海大豆生态区和南方大豆生态区的133份大豆地方种质,在2021年连江春季、福清春季和秋季3个环境下对鲜籽粒可溶性糖含量进行表型测定,结合82187个高质量SNP标记,基于混合线性模型MLM(Q+K)对可溶性糖含量进行全基因组关联分析,挖掘可溶性糖含量显著相关的SNP位点,并以显著SNP位点为中心,两端各扩展119.07 kb连锁不平衡衰减距离为候选区间,根据候选区间内基因的注释和组织表达信息预测候选基因。【结果】3个环境下,鲜籽粒可溶性糖含量的变异范围为3.37—33.84 mg·g^(-1),遗传变异系数为24.59%—32.69%,可溶性糖含量遗传率为68.14%。通过全基因组关联分析,连江春季、福清春季和秋季3个环境下分别检测到与鲜籽粒可溶性糖含量显著关联的SNP有6、8和22个,表型变异解释率为12.43%—29.27%,以表型变异解释率较高的9个显著SNP位点所在的候选区间进行搜索,共获得86个基因,结合基因注释和组织表达信息,进一步筛选到9个候选基因,主要涉及转录因子、糖蛋白家族和糖类合成转运等生物学过程。其中,Glyma.01g016500、Glyma.13g042100、Glyma.16g131800和Glyma.16g155300在大豆种子及荚中表达水平较高,可作为大豆鲜籽粒可溶性糖的最具潜力候选基因。【结论】通过全基因组关联分析,检测到36个与鲜籽粒可溶性糖含量显著关联的SNP,进一步筛选出9个候选基因可能参与大豆鲜籽粒可溶性糖含量的调控,其中,Glyma.01g016500、Glyma.13g042100、Glyma.16g131800和Glyma.16g155300可作为调控大豆鲜籽粒可溶性糖含量的关键目标基因。

急性脑出血模型大鼠脑组织中差异表达基因测序的验证及功能分析

背景:急性脑出血中存在差异表达的基因,这些基因与脑出血发生发展有关。目的:筛选急性脑出血大鼠模型脑组织中差异表达的基因和关键基因,并采用qPCR进行验证,分析关键基因与脑出血后神经功能、脑组织含水量的关系。方法:78只SD大鼠随机分为2组:脑出血组大鼠于右侧尾状核部位注射胶原酶构建脑出血模型,假手术组大鼠于相同部位注射等量生理盐水。运用TRIzol法将2组大鼠的脑组织提取出RNA,转录组测序,筛选急性脑出血脑组织的差异表达的基因,经过qPCR验证,分析基因与脑出血后神经功能、脑组织含水量的关系,并结合生物信息学对关键基因进行GO、KEGG功能富集分析。结果与结论:①筛选出10个关键基因,分别是CXCL8、SERPINE1、TFPI2、CXCR4、GDA、KCNQ5、ERICH3、SCN3B、CACNA1E、CCL20;②脑出血组的关键基因GDA、KCNQ5、ERICH3、SCN3B、CACNA1E含量低于假手术组(P<0.05),CXCL8、SERPINE1、TFPI2、CXCR4、CCL20含量高于假手术组(P<0.05);③关键基因GDA、KCNQ5、ERICH3、SCN3B、CACNA1E含量与脑组织含水量、神经功能缺损评分正相关(P<0.05),CXCL8、SERPINE1、TFPI2、CXCR4、CCL20含量与脑组织含水量、神经功能缺损评分负相关(P<0.05);④GO分析显示基因在生物过程差异表达基因主要富集于白细胞趋化性、趋化因子介导的信号通路;细胞组成差异表达基因主要富集于阳离子通道复合物、离子通道复合物;分子功能差异表达基因主要富集于门控通道活动、离子通道活动;⑤KEGG分析示基因集中于TNF信号通路、谷氨酸能突触、GABA能突触;⑥结论:在脑出血中出现差异表达的基因为CXCL8、SERPINE1、TFPI2、CXCR4、GDA、KCNQ5、ERICH3、SCN3B、CACNA1E、CCL20,这些基因与脑出血后脑组织含水量、神经功能相关,这些基因主要富集在细胞组分、结合功能、细胞突起等相关的生物学功能上。

谷子籽粒类黄酮含量和粒色的QTL定位

谷子(Setaria italica L.)是我国北方地区重要的粮食作物,籽粒营养丰富,且富含多种类黄酮物质,对生长发育和品质形成发挥着重要作用。目前谷子籽粒类黄酮合成及粒色形成相关调控机制研究较少。分析谷子类黄酮含量及粒色性状相关的QTL,为类黄酮合成关键基因的精细定位、克隆及功能研究奠定基础,同时,也为揭示谷子类黄酮合成及代谢机制和培育富含类黄酮谷子品种提供技术支撑。本研究以红粒色高类黄酮品种金苗红酒谷和黄粒色低类黄酮品种豫谷28为亲本构建的包含150个家系的重组自交系(RIL)群体为试验材料,在谷子成熟期对籽粒粒色和类黄酮含量相关性状进行分析。同时,采用复合区间作图法(composite interval mapping,CIM)对粒色和类黄酮含量进行QTL定位与分析,并对QTL置信区间内的候选基因进行预测。相关性分析表明,类黄酮含量与粒色呈显著正相关。共定位到4个与类黄酮含量相关和11个与粒色相关的QTL,分别位于1号、2号、5号、6号、7号、8号和9号染色体上,单个QTL的表型贡献率为2.01%~29.25%,6个为主效QTL,其中,qSC1-2和qFLA1-1、qSC7-1和qFLA7-1、qSC9-3和qFLA9-1为2个性状下共同定位到的QTL。通过基因预测与功能注释,筛选出QTL置信区间内5个与类黄酮物质合成及代谢相关的候选基因,表明类黄酮物质的合成、代谢及利用相关基因极有可能控制了这些基因的表达。15个QTL分别聚集于7条染色体上,基于基因功能注释,共筛选了5个与谷子类黄酮合成及代谢相关的候选基因,表明不同QTL位点参与到了共同遗传机制,并可通过分子标记辅助选择进行类黄酮合成及代谢等有利基因的聚合育种。

玉米籽粒氮含量遗传位点挖掘及候选基因预测

玉米籽粒氮含量与品质紧密相关,其遗传机制的解析对玉米品质育种具有重要意义。本研究以252份玉米自交系为关联群体,利用贝叶斯信息与连锁不平衡迭代嵌套式模型(BLINK,bayesian-informationandlinkage-disequilibrium iteratively nested keyway)、固定随机循环概率模型(FarmCPU,fixed and random model circulating probability unification)、一般线性模型(GLM,general linear model)、混合线性模型(MLM,mixed linear model)、多位点混合线性模型(MLMM,multiple loci mixed model)和逐步排它性混合线性模型(SUPER,settlement of MLM under progressively exclusive relationship)等方法分别对其籽粒氮含量进行全基因组关联分析。共鉴定到13个与籽粒氮含量显著关联的SNP(P<3.64E-07)。BLINK、FarmCPU、GLM、MLM、MLMM和SUPER方法分别检测到6个、3个、7个、4个、2个和4个SNP位点。其中,S3_8879213在5种方法中均能检测到,S9_146173702在4种方法中均能检测到,S5_114774030和S7_182217338在3种方法中均能检测到,S1_10906326和S1_177528813在2种方法中均能检测到。共挖掘25个相关候选基因,其中Zm00001eb275080和Zm00001eb330700可能是影响玉米籽粒氮含量的重要候选基因。

枸杞SWEET基因家族鉴定及其与可溶性糖含量关系

【目的】糖外排转运蛋白(sugars will eventually be exported transporters,SWEETs)在植物生长发育过程中发挥重要作用,解析SWEETs基因在枸杞果实发育过程中对糖积累作用,为进一步揭示SWEETs基因在枸杞果实发育过程中的作用提供参考。【方法】用生物信息学方法对枸杞SWEET基因(LbaSWEETs)进行全基因组鉴定,并用已发表的转录数据分析LbaSWEETs在果实发育时期的基因表达情况。【结果】枸杞SWEET基因家族共有37个成员,随机分布于10条染色体上,分别编码152~621个氨基酸,蛋白质分子质量为16.87~69.97 kD,等电点为4.96~9.86。亚细胞定位预测位于叶绿体或质膜,大多数含有7个跨膜螺旋。系统进化分析发现,37个LbaSWEETs蛋白可分为4个亚群,每个亚群的基因结构和保守基序组成相似。启动子元件分析表明:Lba-SWEETs基因启动子富含大量激素响应、逆境胁迫和生长发育响应元件。转录组数据和qRT-PCR分析表明:LbaSWEET9和LbaSWEET29基因表达量随果实成熟呈现显著增加。相关性分析结果表明,LbaSWEET9和LbaSWEET29基因表达量与果糖含量呈显著正相关。【结论】LbaSWEET9和LbaSWEET29基因是果糖积累的关键基因。

不同温度对羊肚菌淀粉代谢的调控研究

研究了不同温度对淀粉培养基中羊肚菌菌丝生长、淀粉酶活[腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)、α-淀粉酶、β-淀粉酶、淀粉分支酶(DBE)、淀粉脱分支酶(SBE)]、淀粉含量(直链淀粉、支链淀粉)和淀粉相关酶基因表达的影响。结果表明:在10—25℃温度条件下,随着温度的增加,淀粉培养基上菌丝生长速度加快,菌丝浓密度和菌丝尖端分叉增加;AGPase、DBE、α-淀粉酶、β-淀粉酶在20℃下活性最高,SBE则在10℃下活性最高。直链淀粉含量和支链淀粉剩余含量在10℃下最高。相关性分析结果显示,温度与α-淀粉酶活性和SBE活性相关性不显著,与β-淀粉酶活性、AGPase活性、DBE活性呈显著负相关,与直链淀粉含量和支链淀粉含量呈极显著负相关。综上,在15—20℃温度条件下,羊肚菌对培养基中的淀粉代谢能力最强,10℃低温或者25℃高温都不利于羊肚菌对培养基质中淀粉的利用。研究可为羊肚菌的菌种制作和人工种植提供理论支撑。