Agri Gene最新文献

Improving the efficiency of production to reduce the environmental footprints is pivotal to the sustainability of livestock systems. Despite the advances in cattle feed efficiency (FE) measurement and identification of potential mechanisms involved, much is still unclear regarding the genetic and biological basis of this trait. Nevertheless, lipid and carbohydrate metabolism have been outlined as important in determining efficient and inefficient animals. To address the role of genes partaking in these processes and previously involved with residual feed intake (RFI), we carried out a liver expression profile in Nelore steers (n = 83). Six target genes (FABP1, FADS2, PPP1R26, RGS2, SLC2A5, and UCP2) were measured by qPCR analysis. A general linear mixed model approach was applied to associate them with dry matter intake (DMI), body weight (BW), metabolic BW (MBW, kg), DMI as a percentage of BW (DMI%BW), and average daily gain (ADG, kg/d). Residual feed intake (RFI), feed conversion ratio (FCR), feed efficiency (FE), Kleiber index (KI), and relative growth rate (RGR) were also evaluated. Our results support that increased expression of FABP1 gene was associated with enhanced values for RFI and DMI. Likewise, higher expression level of SLC2A5 was related to higher KI and RGR. There was no phenotypic correlation between RFI and ADG, BW, and MBW. The positive correlations between FABP1 and SLC2A5, and between FABP1 and FADS2 gene expression suggest a putative co-regulation affecting feed efficiency phenotypes.

Gonadotropin-releasing hormone (GnRH) is a key neuropeptide of vertebrates, involved in gonadal maturation and primarily regulated by the hypothalamic-pituitary-gonadal axis. The full length GnRH-like cDNA isolated from the cerebral ganglion of Haliotis discus hannai, encodes a deduced protein of 216 amino acids with a theoretical molecular mass of 23.36 kDa and an isoelectric point of 7.72. The GnRH transcript comprises a putative signal peptide, a GnRH dodecapeptide, a proteolytic processing site, and a GnRH associated peptide (GAP). Comparative structural analysis revealed that the cloned sequence shares relatively high homology with other molluscan species and a lower degree of amino acid identity with GnRH of piscine vertebrates. Phylogenetic comparison with other known GnRH genes revealed that the GnRH-like mRNA of H. discus hannai is most closely related to the marine gastropod, H. laevigata. Three-dimensional homology structure of H. discus hannai GnRH and GAP exhibited a helix-loop-helix structure. Quantitative PCR assay demonstrated wide expression of GnRH in all ganglia, among them cerebral ganglion exhibited the highest expression level. Significantly higher expression was observed in cerebral ganglion and gonadal tissues at higher effective accumulative temperature (1000 °C). In situ hybridization showed that the GnRH expressing neurosecretory cells distributed throughout the cortex of the cerebral ganglion. These results suggest that GnRH synthesized from the cerebral ganglia may be involved in gonadal maturation and regulating the secretion of other reproductive hormones.

Different fat ingredients and their fatty acids may influence the expression of genes responsible to encode enzymes and proteins linked to adipose tissue deposition, influencing beef quality. Therefore, the objective was to analyze the expression of PPARA, SREBF1 and genes involved in lipid metabolism in longissimus thoracis (LT) muscle of cattle fed diets containing soybean or cottonseed with or without vitamin E. Twenty-eight bulls were used in a completely randomized design using a 2 × 2 factorial arrangement. The inclusion of soybean and cottonseed in the diets provided 64.8 g kg⁻¹ and 65.6 g kg⁻¹ of ether extract, respectively, and vitamin E supplementation was 2500 IU per day. The PPARA expression was greater and SREBF1 expression was lower in the muscle of animals fed soybean (P < .01). Vitamin E reduced the expression of SREBF1 in animals fed cottonseed and increased its expression in animals fed soybean (P < .01). Expression of LPL and ACACA increased when bulls were fed with soybean (P < .01) and their expression was upregulated when animals received vitamin E (P < .03). Expression of SCD was higher when cottonseed and no vitamin E diet were used (P < .01). In conclusion, supplementation with vitamin E alters the expression of genes involved in lipid metabolism in LT muscle, indicating that α-tocopherol is a cell-signaling molecule.

The larva of the Japanese buff-tip moth (Phalera flavescens) has a novel N-acetyllactosamine-binding lectin, termed Phalera flavescens agglutinin (PFA). It has been suggested that the PFA gene evolved from a lysozyme gene through the loss of lysozyme activity sites. In this study, we investigated whether the PFA gene is evolving through positive selection or by relaxation of functional constraint. For this purpose, we sequenced several PFA-orthologous genes from P. assimilis, P. takasagoensis, and P. bucephala, and compared synonymous and non-synonymous changes to examine the state of natural selection. Although a number of non-synonymous changes were observed on several branches of the gene tree, these effects may have been caused by relaxation of a functional constraint rather than a mechanism of positive selection. Therefore, it is reasonable to conclude that a lysozyme gene in the common ancestor of the Phalera (genus) species lost its lysozyme activity and accumulated mutations during the evolution of the species. Although the actual function of PFA in the moth species is as yet unknown, the gene probably obtained the N-acetyllactosamine-specific lectin activity, collaterally.

The entomopathogenic fungus Beauveria bassiana is used as a natural pest killer in many agricultural systems due to its power of overcoming the host immune system. This is partially due to its genome content that expresses key proteins involved in its virulence. In this study, we used Real-Time PCR technique to analyze the relative expression at 48 and 72 h post inoculation of the Hyd1, Hyd2, Bbchit1, Cdep1, Bbbeas, Bbbsls and Vlp4 genes implicated in the pathogenesis process of an indigenous strain (LTB) and a commercial strain (IND) of B. bassiana. This analysis revealed a higher induction of Bbbeas, Bbbsls and Vlp4 genes by the LTB strain when comparing to the IND strain and the calibrator. Furthermore, a more rapid repression of Hyd1 and Hyd2 gene was notable by LTB strain. No significant difference was recorded by the expression of the Cdep1 gene between the test samples and the control. Finally, a significant difference was recorded with the expression of Bbchit1 gene by the IND strain 72 h post-inoculation. In conclusion, these results suggest that B. bassiana strains have differential expression of virulence genes that could reflect adaptation to their geographical environment and could help classifying their entomopathogenic efficacy accordingly.

Fighting late blight, economically the most important of potato diseases, is greatly hampered by rapid changes in the populations of the pathogen Phytophthora infestans: new pathotypes turn up owing to pathogen evolution and migration and overcome potato varieties that were previously considered resistant. Early recognition of the changes in P. infestans populations would greatly assist potato protection against late blight. The pathogenicity of P. infestans depends on the (a)virulence genes (Avr genes), among which the best known are the genes encoding RXLR effectors. This is the first report on polymorphism of these genes when characterized by single-strand conformation polymorphism (SSCP) analysis. Highly reproducible SSCP patterns combine electrophoretic zones corresponding to the Avr alleles. Ten Avr genes were studied in two series of P. infestans samples: single cell lines obtained from the isolates collected in the potato genetic collection of the N.I. Vavilov Institute of Plant Genetic Resources (VIR), Pushkin, St. Petersburg, and the reference lines from the Western European and USA collections. The Avr3b, Avr4, and Avr8 genes were monomorphic, while in Avr1, Avr2, Avr3a, Avr9, Avr-blb1, Avr-blb2, and Avr-vnt1, we discerned two to five SSCP patterns, with their frequencies different in two series of P. infestans lines. Sequences of Avr alleles differed in synonymous and non-synonymous single nucleotide substitutions, with 93–100% identity between variants. When Avr polymorphisms were compared with the profiles of virulence factors recognized with the Mastenbroeck-Black differentials, the acceptable agreement between two independent indices was observed only for Avr1, Avr3a and Avr4.

The ascomycete Colletotrichum falcatum is the causal agent of red rot of sugarcane, infecting stalks which are economically important for extraction of sugar. Since the pathogen is considered as the most destructive disease in many sugarcane growing countries it gained much attention to decipher its lifestyle. In this study, we have sequenced in planta transcriptome of C. falcatum under Illumina Hi-Seq platform and expanded our search towards finding the Small Secretory Proteins (SSPs) expressed during the host-pathogen interactions. Our previous reports from genome and transcriptome of C.falcatum data provided 768 and 884 SSPs were predicted respectively. The in planta secretory proteins were further mapped and localized with the help of bioinformatics pieplines such as TargetP and SignalP with the default parameters resulted in localizing 739 sequences to secretory pathway, 27 as mitochondrion and two contained chloroplast signal peptides. Further, the predicted secretory proteins were grouped into classical and non-classical proteins and these secreted proteins and 56 transmembrane helices were classified using GO, which revealed that signal peptides have a probable role in stabilizing fungal secretory proteins in the host system during pathogenesis. These small secreted proteins were further identified as crucial key pathogenic determinants from in planta transcriptome analysis. The repertoire of C. falcatum effectors prediction from in vitro and in planta transcriptome identified several putative genes which are involved in biotrophy-necrotrophy in functionally diverse patterns and this will facilitate further analysis of stage specific genes, fungal pathogenicity determinants and characterizing the expression of SSPs in in planta.

A maize gene coding for an E2F regulatory protein located in a quantitative trait locus (QTL) for Fusarium ear rot resistance was cloned and transgenically introduced into maize callus. Several of the transformants were more resistant to feeding by corn earworms and fall armyworms, and retarded growth of Fusarium proliferatum compared to GUS control transformants. More effective transformants contained higher levels of E2F product than GUS controls as indicated by antibody detection. Increased and decreased levels of regulated proteins were noted in E2F overexpressing compared to GUS expressing control transformants. These differentially produced proteins were previously reported to be interactors with the E2F protein, suggesting E2F is affecting the production of these proteins. Other proteins coded for by genes reported to interact with the relevant E2F protein and associated phenotypic effects that could be promoting resistance include those that would increase cell resistance to water stress, increase the presence of reactive oxygen species, and increase the density of indigestible components. Although the full complex of responsible proteins regulated by the E2F examined that promote resistance to insects and fungi remains to be determined, overproduction of the E2F in transgenic callus enhances resistance to some maize insect and fungal pests.

Rice tungro disease (RTD) is the most important viral disease of rice which limits its production and productivity in major rice growing regions of the world. The disease is caused by the combined action of Rice tungro bacilliform virus (RTBV) and Rice tungro spherical virus (RTSV). The RTBV is primarily responsible for symptom development while RTSV encodes proteins required for virus transmission. In this study, we developed an RNAi gene construct containing highly conserved partial sequences of coat protein 3 (CP3) gene of RTSV. The transgenic rice plants were developed in the background of japonica rice cultivar Taipei-309 through Agrobacterium mediated genetic transformation. The transgene showed stable inheritance as determined by PCR and Southern hybridization analyses. Two homozygous transgenic lines from the T₄ generation were inoculated by virus through viruliferous insect vectors. These lines showed highly resistant phenotypes against the tungro disease which was further supported by studies of plant morphology and yield attributes. Also, the transgenic lines showed an inability to transmit the virus complex which could be due to suppression of RTSV proteins involved in virus transmission through insects. This study shows that CP3 of RTSV is a key target gene for development of RNAi mediated tungro disease resistance in rice.

The Japanese apricot (Prunus mume Sieb. et Zucc.) is a typical climacteric fruit which loses commercial value during processing when the surface color turns yellow. In our study, treatment with nordihydroguaiaretic acid (NDGA), an abscisic acid (ABA) synthesis inhibitor, delayed the increase of ethylene and decrease of firmness towards ripening, and retarded the degradation of chlorophyll and the accumulation of carotenoids including β-carotene and lycopene through the expression of PmCHL (coding for chlorophyllase), PmGGPPS (coding for geranylgeranyl diphosphate synthase), PmPDS (coding for phytoene desaturase), PmPSY (coding for phytoene synthases), and PmLCYB (coding for lycopene beta-cyclase). NDGA inhibited the ABA synthesis through PmNCED1 and these results show that ABA may affect the ripening of the Japanese apricot by influencing ethylene production and the expression of PmACS (coding for ACC synthase), PmACO (ACC oxidase) and the ethylene-responsive gene PmERF (ethylene-responsive transcription factor), and thus that ethylene and ABA may interact during fruit ripening in climacteric fruit.