sunTILL: a TILLING resource for gene function analysis in sunflower

<p>Abstract</p> <p>Background</p> <p>Cultivated sunflower (<it>Helianthus annus </it>L.) is a globally important oilseed crop, subjected to intensive genetic and genomic studies. Although classical mutagenesis has successfully been applied to <it>Helianthus </it>genus in the past, we have developed the first sunflower TILLING resource.</p> <p>Results</p> <p>To balance the maximum mutation density with an acceptable plant survival rate, a 'kill curve' analysis was first conducted with different ethylmethanesulfonate (EMS) dosages and different exposure times. According to the germination rate, a treatment with 0.7% EMS for 6 h was chosen. An M₂progeny of 3,651 fertile plants was obtained. Totally, 4.79% of the whole population showed clear aberrant phenotypes. A microsatellite analysis on a representative sample of the original seed stock and mutant lines confirmed the uniformity of the genetic background of plant material. The TILLING procedure was successfully applied to sunflower genome, initially by a <it>Cel</it>I-nuclease mismatch cleavage assay coupled with a DNA-pooling level test. To investigate the efficiency of the mutagenic treatment, a pilot screening was carried out on 1,152 M₂ lines focusing on four genes, three involved in the fatty acid biosynthetic pathway and one for downy mildew resistance. A total of 9 mutant lines were identified and confirmed by sequencing; thereby, the estimated overall mutation frequency for the pilot assay resulted to be 1/475 kb.</p> <p>Conclusion</p> <p>A first TILLING population for a high throughput identification of EMS-induced point mutations in sunflower genome has been successfully obtained. This represents a powerful tool to a better understanding of gene function in sunflower.</p

Structural Differences in KIR3DL1 and LILRB1 Interaction with HLA-B and the Loading Peptide Polymorphisms: In Silico

KIR3DL1 and LILRB1 interact with HLA class I. Using KIR3DL1/HLA-B interaction to set up the procedure, structural immune-informatics approaches have been performed in LILRB1/HLA-B alleles’ combination also considering the contribution of the HLA bound peptide. All KIR3DL1 alleles interact strongly with HLA-B alleles carrying Bw4 epitope and negative charged amino acid residues in peptide position P8 disrupt KIR3DL1 binding. HLA-B alleles carrying Ile 194 show a higher strength of interaction with LILRB1 in all the analyzed haplotypes. Finally, we hypothesize a contribution of the amino acid at position 1 of the HLA bound peptide in the modulation of HLA-B/LILRB1 interaction

structural differences in kir3dl1 and lilrb1 interaction with hla b and the loading peptide polymorphisms in silico evidences

KIR3DL1 and LILRB1 interact with HLA class I. Using KIR3DL1/HLA-B interaction to set up the procedure, structural immune-informatics approaches have been performed in LILRB1/HLA-B alleles' combination also considering the contribution of the HLA bound peptide. All KIR3DL1 alleles interact strongly with HLA-B alleles carrying Bw4 epitope and negative charged amino acid residues in peptide position P8 disrupt KIR3DL1 binding. HLA-B alleles carrying Ile 194 show a higher strength of interaction with LILRB1 in all the analyzed haplotypes. Finally, we hypothesize a contribution of the amino acid at position 1 of the HLA bound peptide in the modulation of HLA-B/LILRB1 interaction

Stimulation of S1PR5 with A-971432, a selective agonist, preserves blood-brain barrier integrity and exerts therapeutic effect in an animal model of Huntington's disease

Huntington's disease (HD) is themost common neurodegenerative disorder for which no effective cure is yet available. Although several agents have been identified to provide benefits so far, the number of therapeutic options remains limited with only symptomatic treatment available. Over the past few years, we have demonstrated that sphingolipid-based approachesmay open the door to newandmore targeted treatments for the disease. In this study, we investigated the therapeutic potential of stimulating sphingosine-1-phosphate (S1P) receptor 5 by the new selective agonist A-971432 (provided by AbbVie) in R6/2mice, a widely used HD animalmodel. Chronic administration of low-dose (0.1mg/kg) A-971432 slowed down the progression of the disease and significantly prolonged lifespan in symptomatic R6/2mice. Such beneficial effects were associated with activation of pro-survival pathways (BDNF, AKT and ERK) and with reduction of mutant huntingtin aggregation. A-971432 also protected blood-brain barrier (BBB) homeostasis in the same mice. Interestingly, when administered early in the disease, before any overt symptoms, A-971432 completely protected HDmice fromthe classic progressivemotor deficit and preserved BBB integrity. Beside representing a promising strategy to take into consideration for the development of alternative therapeutic options for HD, selective stimulation of S1P receptor 5may be also seen as an effective approach to target brain vasculature defects in the disease

Sphingolipids and impaired hypoxic stress responses in Huntington disease.

Huntington disease (HD) is a debilitating, currently incurable disease. Protein aggregation and metabolic deficits are pathological hallmarks but their link to neurodegeneration and symptoms remains debated. Here, we summarize alterations in the levels of different sphingolipids in an attempt to characterize sphingolipid patterns specific to HD, an additional molecular hallmark of the disease. Based on the crucial role of sphingolipids in maintaining cellular homeostasis, the dynamic regulation of sphingolipids upon insults and their involvement in cellular stress responses, we hypothesize that maladaptations or blunted adaptations, especially following cellular stress due to reduced oxygen supply (hypoxia) contribute to the development of pathology in HD. We review how sphingolipids shape cellular energy metabolism and control proteostasis and suggest how these functions may fail in HD and in combination with additional insults. Finally, we evaluate the potential of improving cellular resilience in HD by conditioning approaches (improving the efficiency of cellular stress responses) and the role of sphingolipids therein. Sphingolipid metabolism is crucial for cellular homeostasis and for adaptations following cellular stress, including hypoxia. Inadequate cellular management of hypoxic stress likely contributes to HD progression, and sphingolipids are potential mediators. Targeting sphingolipids and the hypoxic stress response are novel treatment strategies for HD

Age-Related Modifications in Circulating IL-15 Levels in Humans

Aging is associated to a progressive establishing of a chronic inflammatory state linked to a continuous long exposure to antigens. Since IL-15 stimulates the proliferation of memory T cells and the immunosenescence is characterized by accumulation of memory T cells and exhaustion of naive T cells, we analyzed IL-15 levels in sera from 30 ultralongeval subjects with respect to those from young and old adults. IL-15 levels were assayed by immunoenzymatic methods. Ultralongeval subjects displayed significantly higher IL-15 levels with respect to both young and old controls. No statistical difference was found between old and young controls. These findings may explain, at least in part, the characteristic increase of memory cells in immunosenescence and the capacity of the immune system of centenarians to defend itself from infections through immune-inflammatory responses

Effect of levodopa on interleukin-15 and RANTES circulating levels in patients affected by Parkinson's disease.

Parkinson's disease (PD) is an extra-pyramidal neurodegenerative disorder, in which alterations of the immune system are involved. Interleukin (IL)-15 stimulates cellular immune response and induces growth and differentiation of various immune cells. RANTES, promoting leukocyte infiltration to sites of inflammation, mediates the trafficking and homing of immune cells. To clarify the potential effect of levodopa on the immunological network of PD, we analyzed IL-15 and RANTES serum levels in PD patients, treated or not with levodopa, and in healthy donors. Levodopa-treated patients showed significantly higher IL-15 and RANTES circulating levels with respect to healthy controls and higher, although not significantly, levels with respect to untreated patients. So, we hypothesize that the immunological alterations found in PD may be linked, at least in part, to levodopa therapy

Evaluation of contrast-enhanced digital mammography (CEDM) in the preoperative staging of breast cancer: Large-scale single-center experience.

One of the most important indications for contrast-enhanced breast imaging is the presurgical breast cancer (BC) staging. This is a large-scale single-center experience which evaluates the role of CEDM in presurgical staging and its impact on surgical planning. The aims of this retrospective study were to define the diagnostic performance of CEDM in the presurgical setting and to identify which types of patients could benefit from having CEDM. We selected 326 patients with BC who underwent CEDM as preoperative staging and had breast cancer-related surgery at our institution. We analyzed those cases in which CEDM led to additional imaging or biopsy and those in which it changed the type of surgery that was planned according to conventional breast imaging (CI) techniques (digital mammography, tomosynthesis and bilateral handheld ultrasound). CEDM sensitivity in identifying the index lesion and sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, and accuracy in the correct preoperative staging of BC of the whole population and in various subgroups were calculated. CEDM sensitivity for the index lesion was 98.8% (322/326), which led to additional breast imaging in 23.6% (77/326) of patients and additional biopsies in 17.5% (57/326). CEDM changed the type of surgery in 18.4% (60/326). In the preoperative breast cancer staging, CEDM sensitivity, specificity, PPV, NPV, and accuracy produced results of 93%, 98%, 90%, 98%, and 97%, respectively. CEDM performance was better in patients with palpable lesions. CEDM has an excellent diagnostic performance in the presurgical staging of BC. Symptomatic patients with palpable lesions benefitted most from preoperative CEDM, with a statistically significant difference compared with nonpalpable

Differential expression of sphingolipid metabolizing enzymes in spontaneously hypertensive rats: a possible substrate for susceptibility to brain and kidney damage

Alterations in the metabolism of sphingolipids, a class of biologically active molecules in cell membranes with direct effect on vascular homeostasis, are increasingly recognized as important determinant in different vascular disorders. However, it is not clear whether sphingolipids are implicated in the pathogenesis of hypertension-related cerebrovascular and renal damage. In this study, we evaluated the existence of possible abnormalities related to the sphingolipid metabolism in the brain and kidneys of two well validated spontaneously hypertensive rat strains, the stroke-prone (SHRSP) and the stroke-resistant (SHRSR) models, as compared to the normotensive Wistar Kyoto (WKY) rat strain. Our results showed a global alteration in the metabolism of sphingolipids in both cerebral and renal tissues of both hypertensive strains as compared to the normotensive rat. However, few defects, such as reduced expression of enzymes involved in the metabolism/catabolism of sphingosine-1-phosphate and in the de novo biosynthetic pathways, were exclusively detected in the SHRSP. Although further studies are necessary to fully understand the significance of these findings, they suggest that defects in specific lipid molecules and/or their related metabolic pathways may likely contribute to the pathogenesis of hypertensive target organ damage and may eventually serve as future therapeutic targets to reduce the vascular consequences of hypertension