35 research outputs found

    Gene effects and heterosis for grain Fe and Zn content in barnyard millet (Echinochloa frumentacea (Roxb.) link)

    Get PDF
    Barnyard millet (Echinochloa frumentacea) is an unexplored nutri-rich crop that thrives well in harsh environments and supports many small farmers in Southern and Eastern Asia. Although it has rich sources of micronutrients, the genetic studies are very limited which further impedes in its genetic improvement. Therefore, we attempted to assess the genetic diversity for Fe and Zn content in 40 barnyard millet germplasm and to evaluate the combining ability and heterosis in sixteen F1 cross combinations through line × tester model. The Mahalanobis D2 analysis grouped the 40 genotypes into nine different clusters. Cluster III and I were the largest groups containing 22 and 6 genotypes, respectively and the rest of seven clusters were the lowest group containing one or two genotypes. Positive correlation was observed between Fe and Zn content though both had a non-significant association with grain yield. This indicate that there would not be any compromise on increase or decrease of grain yield while breeding for varieties high in micronutrient content. Combining ability analysis revealed that lines, testers, and their interaction components are significant. The predictability ratio indicated the predominance of additive variance for Fe and Zn content and non-additive variance in the inheritance of yield components. Genotypes, ACM 331, ACM 333, ACM 335 and MA 10 exhibited positive gca effects for Fe and Zn content and grain yield. Two cross combinations, ACM 331 × ACM 335 and ACM 331 × MA 10 involved one or both the parents with good gca effects exhibited, high mean, positive mid-parent heterosis and sca effects for Fe, Zn content and yield components. Thus, the present investigation provided a significant understanding of the gene action and the possibility of utilizing the selected parents and cross combination for exploiting micronutrient traits in barnyard millet crop

    Genetic and genomic resources, and breeding for accelerating improvement of small millets: current status and future interventions

    Get PDF
    Current agricultural and food systems encourage research and development on major crops, neglecting regionally important minor crops. Small millets include a group of small- seeded cereal crops of the grass family Poaceae. This includes finger millet, foxtail millet, proso millet, barnyard millet, kodo millet, little millet, teff, fonio, job’s tears, guinea millet, and browntop millet. Small millets are an excellent choice to supplement major staple foods for crop and dietary diversity because of their diverse adaptation on marginal lands, less water requirement, lesser susceptibility to stresses, and nutritional superiority compared to major cereal staples. Growing interest among consumers about healthy diets together with climate-resilient features of small millets underline the necessity of directing more research and development towards these crops. Except for finger millet and foxtail millet, and to some extent proso millet and teff, other small millets have received minimal research attention in terms of development of genetic and genomic resources and breeding for yield enhancement. Considerable breeding efforts were made in finger millet and foxtail millet in India and China, respectively, proso millet in the United States of America, and teff in Ethiopia. So far, five genomes, namely foxtail millet, finger millet, proso millet, teff, and Japanese barnyard millet, have been sequenced, and genome of foxtail millet is the smallest (423-510 Mb) while the largest one is finger millet (1.5 Gb). Recent advances in phenotyping and genomics technologies, together with available germplasm diversity, could be utilized in small millets improvement. This review provides a comprehensive insight into the importance of small millets, the global status of their germplasm, diversity, promising germplasm resources, and breeding approaches (conventional and genomic approaches) to accelerate climate-resilient and nutrient-dense small millets for sustainable agriculture, environment, and healthy food systems

    Genetic variability and association studies for yield and its attributes in super-early pigeonpea (Cajanus cajan (l.) Millsp.) Genotypes

    Get PDF
    Twenty-nine super-early pigeonpea genotypes along with an early duration check were evaluated for 12 quantitative traits to assess genetic variability, cause and effect for yield as well as yield contributing traits. High PCV and GCV was observed for the traits viz. plant height, number of branches per plant, pod bearing length, number of clusters per plant, number of number of pods per plant and single plant yield. High heritability associated with high genetic advance as per cent of mean (GAM) was observed for the traits like plant height, pod bearing length, number of clusters per plant and number of branches per plant indicating that these traits were controlled by additive gene action and selection for above traits is advisable. Correlation coefficient analysis revealed that the traits viz. number of number of pods per plant, pod length, number of seeds per pod and days to fifty per cent flowering can be the best selection indices for breeding programme as they show significant positive correlation in favour of single plant yield. Path coefficient analysis showcased the traits with direct and indirect effect on single plant yield as number of pods per plant, plant height, days to maturity, number of branches per plant and days to fifty per cent flowering

    GRB 051028: an intrinsically faint GRB at high redshift?

    Get PDF
    We present multiwavelength observations of the gamma-ray burst GRB 051028 detected by HETE-2 in order to derive its afterglow emission parameters and to determine the reason for its optical faintness when compared to other events. Observations were taken in the optical (2.0m Himalayan Chandra Telescope, 1.34m Tautenburg, 4.2m William Herschel Telescope) and in X-rays (Swift/XRT) between 2.7 hours and 10 days after the onset of the event. The data can be interpreted by collimated emission in a jet with a typical value of pp = 2.4 which is moving in an homogeneous interstellar medium and with a cooling frequency nu_{c} still above the X-rays at 0.5 days after the burst onset. GRB 051028 can be classified as a ``gray'' or ``potentially dark'' GRB. On the basis of the combined optical and Swift/XRT data, we conclude that the reason for the optical dimness is not extra absorption in the host galaxy, but rather the GRB taking place at high-redshift.We also notice the very striking similarity with the optical lightcurve of GRB 050730, a burst with a spectroscopic redshift of 3.967, although GRB 051028 is about 3 mag fainter. We suggest that the bump could be explained by multiple energy injection episodes and that the burst is intrinsically faint when compared to the average afterglows detected since 1997. The non-detection of the host galaxy down to R = 25.1 is also consistent with the burst arising at high redshift, compatible with the published pseudo-z of 3.7 +/- 1.8

    CAG Repeat Variants in the POLG1 Gene Encoding mtDNA Polymerase-Gamma and Risk of Breast Cancer in African-American Women

    Get PDF
    The DNA polymerase-gamma (POLG) gene, which encodes the catalytic subunit of enzyme responsible for directing mitochondrial DNA replication in humans, contains a polyglutamine tract encoded by CAG repeats of varying length. The length of the CAG repeat has been associated with the risk of testicular cancer, and other genomic variants that impact mitochondrial function have been linked to breast cancer risk in African-American (AA) women. We evaluated the potential role of germline POLG-CAG repeat variants in breast cancer risk in a sample of AA women (100 cases and 100 age-matched controls) who participated in the Women's Circle of Health Study, an ongoing multi-institutional, case-control study of breast cancer. Genotyping was done by fragment analysis in a blinded manner. Results from this small study suggest the possibility of an increased risk of breast cancer in women with minor CAG repeat variants of POLG, but no statistically significant differences in CAG repeat length were observed between cases and controls (multivariate-adjusted odds ratio 1.74; 95% CI, 0.49–6.21). Our study suggests that POLG-CAG repeat length is a potential risk factor for breast cancer that needs to be explored in larger population-based studies

    Mitochondrial Disease in Autism Spectrum Disorder Patients: A Cohort Analysis

    Get PDF
    Previous reports indicate an association between autism spectrum disorders (ASD) and disorders of mitochondrial oxidative phosphorylation. One study suggested that children with both diagnoses are clinically indistinguishable from children with idiopathic autism. There are, however, no detailed analyses of the clinical and laboratory findings in a large cohort of these children. Therefore, we undertook a comprehensive review of patients with ASD and a mitochondrial disorder.We reviewed medical records of 25 patients with a primary diagnosis of ASD by DSM-IV-TR criteria, later determined to have enzyme- or mutation-defined mitochondrial electron transport chain (ETC) dysfunction. Twenty-four of 25 patients had one or more major clinical abnormalities uncommon in idiopathic autism. Twenty-one patients had histories of significant non-neurological medical problems. Nineteen patients exhibited constitutional symptoms, especially excessive fatigability. Fifteen patients had abnormal neurological findings. Unusual developmental phenotypes included marked delay in early gross motor milestones (32%) and unusual patterns of regression (40%). Levels of blood lactate, plasma alanine, and serum ALT and/or AST were increased at least once in 76%, 36%, and 52% of patients, respectively. The most common ETC disorders were deficiencies of complex I (64%) and complex III (20%). Two patients had rare mtDNA mutations of likely pathogenicity.Although all patients' initial diagnosis was idiopathic autism, careful clinical and biochemical assessment identified clinical findings that differentiated them from children with idiopathic autism. These and prior data suggest a disturbance of mitochondrial energy production as an underlying pathophysiological mechanism in a subset of individuals with autism

    Cellular Model of Warburg Effect Identifies Tumor Promoting Function of UCP2 in Breast Cancer and Its Suppression by Genipin

    Get PDF
    The Warburg Effect is characterized by an irreversible injury to mitochondrial oxidative phosphorylation (OXPHOS) and an increased rate of aerobic glycolysis. In this study, we utilized a breast epithelial cell line lacking mitochondrial DNA (rho0) that exhibits the Warburg Effect associated with breast cancer. We developed a MitoExpress array for rapid analysis of all known nuclear genes encoding the mitochondrial proteome. The gene-expression pattern was compared among a normal breast epithelial cell line, its rho0 derivative, breast cancer cell lines and primary breast tumors. Among several genes, our study revealed that over-expression of mitochondrial uncoupling protein UCP2 in rho0 breast epithelial cells reflects gene expression changes in breast cancer cell lines and in primary breast tumors. Furthermore, over-expression of UCP2 was also found in leukemia, ovarian, bladder, esophagus, testicular, colorectal, kidney, pancreatic, lung and prostate tumors. Ectopic expression of UCP2 in MCF7 breast cancer cells led to a decreased mitochondrial membrane potential and increased tumorigenic properties as measured by cell migration, in vitro invasion and anchorage independent growth. Consistent with in vitro studies, we demonstrate that UCP2 over-expression leads to development of tumors in vivo in an orthotopic model of breast cancer. Genipin, a plant derived small molecule, suppressed the UCP2 led tumorigenic properties, which were mediated by decreased reactive oxygen species and down-regulation of UCP2. However, UCP1, 3, 4 and 5 gene expression was unaffected. UCP2 transcription was controlled by SMAD4. Together, these studies suggest a tumor-promoting function of UCP2 in breast cancer. In summary, our studies demonstrate that i) the Warburg Effect is mediated by UCP2; ii) UCP2 is over-expressed in breast and many other cancers; iii) UCP2 promotes tumorigenic properties in vitro and in vivo and iv) genipin suppresses the tumor promoting function of UCP2

    Novel mitochondrial mutation in the ND4 gene associated with Leigh syndrome

    No full text
    We analyzed the complete mitochondrial genome of a 3-month-old female child with basal ganglionic lesions and other clinical features suggestive of Leigh syndrome, which is caused by variations in mitochondrial and nuclear genes. Our study revealed a novel, homoplasmic T11984C missense mutation in ND4 gene, which replaces a highly conserved amino acid tyrosine with histidine. Computational analysis showed that this mutation alters the secondary structure of ND4 subunit. As the mutation observed in this study was novel and homoplasmic, we speculate that there could be interplay of this mitochondrial mutation along with nuclear gene(s) in the pathogenesis
    corecore