杜洛克猪HLCS基因组织表达分析及其编码区多态性与剩余采食量的关联

旨在探究羧化全酶合成酶基因(holocarboxylase synthetase,HLCS)在杜洛克猪各组织中的表达情况及其编码区多态性与剩余采食量(residual feed intake,RFI)之间的关系。本研究利用荧光定量PCR检测HLCS基因在杜洛克猪8种组织中的相对表达量;利用PCR和测序在RFI高、低组个体中扩增HLCS基因的编码区用以寻找多态位点,并对获得的位点在杜洛克群体中分型,进而分析多态位点与RFI的关联性。结果表明,HLCS在脂肪组织中表达量最高,肝次之,在心和肌肉中痕量表达。在杜洛克个体中共发现5个多态位点,其中c.1408G>C和c.1976A>G为错义突变位点。在杜洛克群体中,c.1408G>C与RFI关联不显著(P>0.05);c.1976A>G与RFI显著关联(P<0.05),GG基因型个体的RFI比AA基因型个体低0.063 4kg。这些结果表明,HLCS与RFI密切相关,c.1976A>G可作为猪RFI性状选育的潜在分子标记,为进一步开展HLCS基因影响猪剩余采食量的功能鉴定奠定了研究基础。

Heritabilities and genetic and phenotypic correlations of litter uniformity and litter size in Large White sows

Litter uniformity, which is usually represented by within-litter weight coefficient of variation at birth （CVB）, could influence litter performance of sows and the profitability of pig enterprises. The objective of this study was to characterize CVB and its effect on other reproductive traits in Large White sows. Genetic parameters and genetic correlation of the reproductive traits, including CVB, within-litter weight coefficient of variation at three weeks （CVT）, total number born （TNB）, number born alive （NBA）, number born dead （NBD）, gestation length （GL）, piglet mortality at birth （Mo）, piglet mortality at three weeks （M3）, total litter weight at birth （TLW0）, and total litter weight at three weeks （TLW3） were estimated for 2 032 Large White litters. The effects of parity and classified litter size on CVB, CVT, TNB, NBA, NBD, GL, M0, M3, TLW0, and TLW3 were also estimated. The heritabilities of these reproductive traits ranged from 0.06 to 0.17, with the lowest heritability for CVB and the highest heritability for TLW0. Phenotypic and genetic correlations between these reproductive traits were low to highly positive and negative （ranging from -0.03 to 0.93, and -0.53 to 0.93, respectively）. The genetic correlations between TNB and CVB, and between M0 and CVB were 0.32 and 0.29, respectively. In addition, CVB was significantly influenced by parity and litter size class （P〈0.05）. All the results suggest that piglet uniformity should be maintained in pig production practices and pig breeding programs.

冀东滨海平原稻区土壤钾库状况与变化

通过对大面积土壤各形态钾的定位监测,研究了1982~2016年30余年间冀东滨海平原稻区土壤钾库的现状、变化及其影响因素,分析了成土母质、耕种施肥等对该区域土壤钾库的影响。主要结果:(1)冀东滨海平原稻区土壤全钾、缓效钾、速效钾平均含量分别为23.04 g/kg、1615.94 mg/kg、247.37 mg/kg。种稻40~70余年间,各年限土壤全钾、速效钾分别维持在23.96 g/kg、257.41 mg/kg左右。与种稻40年相比,缓效钾年均减少20.19 mg/kg。(2)不同母质土壤全钾、缓效钾、速效钾含量大小顺序为:海相沉积物、泻湖沉积物>河流冲积物;土壤缓效钾/全钾和速效钾/全钾均为海相沉积物、泻湖沉积物>河流冲积物,3种母质发育的土壤速效钾/缓效钾差异不显著;海相沉积物、泻湖沉积物二者之间的各形态钾含量及比值均无显著差异。(3)土壤速效钾与土壤盐分、有机质均呈显著正相关关系;土壤速效钾与有效磷无显著相关关系。主要结论:随种植年限增加,土壤全钾、速效钾无显著变化,缓效钾显著下降。海相沉积物、泻湖沉积物发育的土壤全钾、缓效钾、速效钾的含量均显著高于河流冲积物,土壤速效钾与盐分呈显著正相关关系。稻区土壤钾输入量小于水稻钾的输出量,随着种稻年限的增加,逐渐消耗土壤缓效钾。

Quantitative trait loci for the number of vertebrae on Sus scrofa chromosomes 1 and 7 independently influence the numbers of thoracic and lumbar vertebrae in pigs

Although quantitative trait loci（QTLs） for number of thoracic-lumbar vertebrae have been identified on Sus scrofa chromosomes（SSCs） 1 and 7, the influence of these QTLs on the thoracic and lumbar vertebrae is not clear. The aim of this study was to identify single nucleotide polymorphisms（SNPs） associated with total number of thoracic-lumbar vertebrae and for each trait（number of thoracic and lumbar vertebrae） separately. A total of 581 individuals from an F2 Large White×Minzhu population were genotyped using an SNP60 K chip. Performing a genome-wide association study（GWAS） for total number of thoracic-lumbar vertebrae, 38 significant SNPs were identified in two QTL regions located on SSC1 and SSC7. Performing a GWAS for number of thoracic vertebrae only, 72 significant SNPs were located on SSC7. While performing a GWAS for number of lumbar vertebrae only, 17 significant SNPs were identified on SSC1. Gene mining suggested that the gene encoding orphan nuclear receptor, germ cell nuclear factor（NR6A1） on SSC1 was a strong candidate affecting the number of lumbar vertebrae in pigs. Additionally, genes encoding vertnin（VRTN）, prospero homeobox 2（PROX2）, Finkel-Biskis-Jinkins murine osteosarcoma viral oncogene homolog（FOS）, and transforming growth factor beta 3（TGFB3） may be important candidates affecting the number of thoracic vertebrae in pigs. QTLs on SSC1 and SSC7 independently influenced the numbers of thoracic and lumbar vertebrae. These results shed light on the complex genetic background of vertebrae development in pigs.

Porcine LEM domain-containing 3: Molecular cloning, functional characterization, and polymorphism associated with ear size

Ear size exhibits remarkable diversity in pig breeds. LEM domain-containing 3 （LEMD3） on chromosome 5 is considered as an important candidate for porcine ear size. This is the first study on cloning and characterization of LEMD3 cDNA. The complete cDNA contains 4 843 bp, including a 2 736-bp open reading frame （ORF）, a 37-bp 5＂-untranslated region （UTR） and a 2070-bp 3＂-UTR. The complete LEMD3 gene is 126241-bp and contains 13 exons and 12 introns. The ORF encodes a deduced LEMD3 protein of 911 amino acids, which shares 82-94% nucleic acid and 51-96% amino acid identity with other species. A phylogenetic tree constructed based on the amino acid sequences revealed that the porcine LEMD3 protein was closely related with cattle LEMD3. Resequencing of the ORF and promoter of LEMD3 from Minzhu pig and Large White revealed three single nucleotide polymorphisms （SNPs）： L964C〉A in the complete coding region, L4625A〉G in the 3＂ UTR, and L-394T〉C in the promoter region. Genome-wide association study （GWAS） revealed that all of SNPs were shown significant association with ear size in Large WhitexMinzhu pig intercross population. With conditional GWAS, -Iogl0（P-value） decreased by more than 80% when each of three SNPs was included as a fixed effect. These results suggested direct involvement of LEMD3 or close linkage to the causative mutation for ear size. The findings of this study might form the basis for understanding the genetic mechanism of ear size variation in pigs and provide potential molecular markers for screening ear size diversity in pig breeds.

西北地区小城市衰败街巷空间更新设计研究——以庆城县老城区为例

我国已经进入城镇化发展的中后期,城市的发展已经由大规模的增量建设进入存量优化的新阶段,而作为城镇化发展的主要部分,小城市的持续更新中遇到许多特有的问题,西北地区发展较为缓慢的小城市就普遍存在老城区街巷空间的衰败,这些空间严重影响城市的更新发展。本研究以庆城县老城区为例,提出城市街巷空间更新存在的一些问题,对类似小城市所存在的相关问题提出策略和建议,为西北地区小城市发展更新提供策略。

微波照射下玄武岩冲击破碎特性研究

为了研究微波照射和动态冲击荷载下玄武岩的破碎损伤特性,基于分形理论,利用微波发射装置和SHPB霍普金森动态试验装置,通过收集玄武岩碎块进行颗粒筛分,试验研究微波照射后玄武岩破碎特性变化规律。结果表明:采用分形维数可定量描述玄武岩岩样的破碎程度;在1300W微波功率照射后和0. 4MPa冲击气压作用下岩石破碎程度更大,为微波辅助机械破岩提供借鉴和参考。

Danlou Tablet Improves Chronic Intermittent Hypoxia-Induced Dyslipidemia and Arteriosclerosis by HIF-1α-Angptl4 mRNA Signaling Pathway

Objective:To detect whether Danlou Tablet(DLT)regulates the hypoxia-induced factor(HIF)-1α-angiopoietin-like 4(Angptl4)mRNA signaling pathway and explore the role of DLT in treating chronic intermittent hypoxia(CIH)-induced dyslipidemia and arteriosclerosis.Methods:The mature adipocytes were obtained from3 T3-L1 cell culturation and allocated into 8 groups including control groups(Groups 1 and 5,0.1 mL of cell culture grade water);DLT groups(Groups 2 and 6,0.1 mL of 1,000μg/mL DLT submicron powder solution);dimethyloxalylglycine(DMOG)groups(Groups 3 and 7,DMOG and 0.1 mL of cell culture grade water);DMOG plus DLT groups(Groups 4 and 8,DMOG and 0.1 mL of 1,000μg/mL DLT submicron powder solution).Groups1-4 used mature adipocytes and groups 5-8 used HIF-1α-siRNA lentivirus-transfected mature adipocytes.After 24-h treatment,real-time polymerase chain reaction and Western blot were employed to determine the mRNA and protein expression levels of HIF-1αand Angptl4.In animal experiments,the CIH model in ApoE^(-/-)mice was established.Sixteen mice were complete randomly divided into 4 groups including sham group,CIH model group[intermittent hypoxia and normal saline(2 mL/time)gavage once a day],Angptl4 Ab group[intermittent hypoxia and Angptl4 antibody(30 mg/kg)intraperitoneally injected every week],DLT group[intermittent hypoxia and DLT(250 mg/kg)once a day],4 mice in each group.After 4-week treatment,enzyme linked immunosorbent assay was used to detect the levels of serum total cholesterol(TC)and triglyceride(TG).Hematoxylin-eosin and CD68 staining were used to observe the morphological properties of arterial plaques.Results:Angptl4 expression was dependent on HIF-1α,with a reduction in mRNA expression and no response in protein level to DMOG or DLT treatment in relation to siHIF-1α-transfected cells.DLT inhibited HIF-1αand Angptl4 mRNA expression(P<0.05 or P<0.01)and reduced HIF-1αand Angptl4 protein expressions with DMOG in mature adipocytes(all P<0.01),as the effect on HIF-1αprotein also existed in the presence of siHIF-1α(P<0.01).ApoE^(-/-)mice treated with CIH had increased TG and TC levels(all P<0.01)and atherosclerotic plaque.Angptl4 antibody and DLT both reduced TG and TC levels(all P<0.01),as well as reducing atherosclerotic plaque areas,narrowing arterial wall thickness and alleviating atherosclerotic lesion symptoms to some extent.Conclusion:DLT had positive effects in improving dyslipidemia and arteriosclerosis by inhibiting Angptl4 protein level through HIF-1α-Angptl4 mRNA signaling pathway.