Tissue-specific activation of the osmotin gene by ABA, C2H4 and NaCl involves the same promoter region

The gene encoding the antifungal protein osmotin is induced by several hormonal and environmental signals. In this study, tissue-specific and inducer-mediated expression of the reporter gene beta-glucuronidase (uidA) fused to different fragment lengths of the osmotin promoter was evaluated in transgenic tobacco (Nicotiana tabacum). The region of the promoter between -248 to -108 (Fragment A) was found to be essential and sufficient for inducer (abscisic acid (ABA), C2H4 and NaCl)-mediated expression of the reporter gene. Expression of the reporter gene was developmentally regulated and increased with maturity of leaves, stem and flowers. Expression also was tissue-specific being most highly expressed in epidermis and vascular parenchyma of the stem. The regulators ABA, C2H4 and NaCl exhibited tissue-specific induction of this promoter. The promoter was specifically responsive to C2H4 in flowers at virtually all stages of development, but not responsive in these tissues to ABA or NaCl. Conversely, ABA and NaCl were able to induce reporter gene activity using promoter Fragment A in specific tissues of root where C2H4 was unable to induce activity. Further dissection of the promoter Fragment A into fragments containing either the conserved GCC element (PR); PR/AT; or G/AT sequences, and subsequent testing of these fragments fused to GUS in transgenic plants was performed. These experiments revealed that the promoter fragment containing PR element alone, although required, was barely able to allow responsiveness to C2H4. However, significant C2H4-induced activity was obtained with a promoter fragment containing the AT and PR elements together.     

Aortic and lower-extremity arterial disease: evaluation with MR angiography versus conventional angiography

BACKGROUND: Few data are available regarding the impact of improved depression treatment on daily functioning and disability. METHODS: In two studies of more intensive depression treatment in primary care, patients initiating antidepressant treatment were randomly assigned to either usual care or to a collaborative management programme including patient education, on-site mental health treatment, adjustment of antidepressant medication, behavioural activation and monitoring of medication adherence. Assessments at baseline as well as 4 and 7 months included several measures of impairment, daily functioning and disability: self-rated overall health, number of bodily pains, number of somatization symptoms, changes in work due to health, reduction in leisure activities due to health, number of disability days and number of restricted activity days. RESULTS: Average data from the 4- and 7-month assessments in both studies, intervention patients reported fewer somatic symptoms (OR 0.68, 95% CI 0.46, 0.99) and more favourable overall health (OR 0.50, 95% CI 0.28, 0.91). While intervention patients fared better on other measures of functional impairment and disability, none of these differences reached statistical significance. CONCLUSIONS: More effective acute-phase depression treatment reduced somatic distress and improved self-rated overall health. The absence of a significant intervention effect on other disability measures may reflect the brief treatment and follow-up period and the influence of other individual and environmental factors on disability.     

Phenotype and genotype expression in pseudohomozygous factor VLEIDEN : the need for phenotype analysis

The presence of a DNA mutation is frequently used to define a disease or a risk state. Because DNA typing has become easy and convenient in contrast to protein characterization, it is generally assumed that a mutation if present (or not) at the DNA level will be also present (or not) in the corresponding protein. However, discrepancies between phenotype and genotype can occur. A point mutation in the coagulation factor V gene (G1691-->A, resulting in an Arg506-->Gln amino acid substitution in the factor V molecule [factor VLEIDEN], leading to activated protein C resistance) is the most common genetic risk factor for familial thrombophilia. A pseudohomozygous factor VLEIDEN phenotype would occur if a heterozygous individual for factor VLEIDEN also did not express the "normal" (non-Leiden) factor V allele. However, to date, no data have been available to confirm the presence of only the factor VLEIDEN form in the plasma of these individuals. Platelet mRNA from 2 presumed pseudohomozygous patients and their family members was isolated, the amplified partial cDNAs were sequenced or restricted, and the allelic bands were quantified. Both patients were found to be heterozygous for the G1691-->A substitution at both the DNA and mRNA levels. The presence of either the normal or mutated form of factor V in the patients' plasmas was investigated using a monoclonal antibody to factor V that recognizes an epitope located between residues 307 and 506 of the factor Va heavy chain. No normal factor V could be detected in the plasmas of the 2 propositi. The present data demonstrate absence of a correlation between genotype at position 1691 (at the DNA and mRNA levels) and the corresponding phenotype data found in the plasmas of patients with pseudohomozygous factor VLEIDEN. Overall, these data suggest the existence of heterogeneous genetic "lesions," which interfere with factor V expression, processing, secretion, and/or stability. Because the presence of the factor VLEIDEN molecule in plasma is directly related to pathology, identification and quantification of the circulating forms of factor V in plasma may be required for the diagnosis of individuals with activated protein C resistance.