Stresses induced by the deficiency or excess of trace mineral elements, such as manganese (Mn), represent a common limiting factor for the production of crops like Brassica napus. To identify key genes involved in Mn allocation in B. napus and elucidate the underlying mechanisms, a member of the metal tolerance protein (MTP) family obtained in the previous screening of cDNA library of B. napus under Mn stress was selected as the research subject. Based on the sequence information and phylogenetic analysis, it was named as BnMTP10. It belongs to the Mn-cation diffusion facilitator (CDF) subfamily. Expression of BnMTP10 in yeast significantly improved the tolerance of transformants to excessive Mn and iron (Fe) and reduced the accumulation of Mn and Fe. However, the yeast transformants exhibited no significant changes in tolerance to excess cadmium, boron, aluminum, zinc, or copper. The qRT-PCR results demonstrated that the flowers of B. napus had the highest expression of BnMTP10, followed by roots and leaves. Subcellular localization studies revealed that BnMTP10 was localized in the endoplasmic reticulum (ER). Compared with wild-type plants, transgenic Arabidopsis overexpressing BnMTP10 exhibited enhanced tolerance to excessive Mn stress but showed no significant difference under Fe stress. Correspondingly, under excessive Mn stress, the Mn content in the roots of transgenic Arabidopsis increased significantly. However, under excessive Fe stress, the Fe content in transgenic Arabidopsis did not alter significantly. According to the results, we hypothesize that BnMTP10 may alleviate excessive Mn stress in plants by mediating Mn transport to the ER. This study facilitated our understanding of efficient mineral nutrients, and provided theoretical foundations and gene resources for breeding B. napus.
Brassica napus/genetics* ; Manganese/metabolism* ; Plants, Genetically Modified/genetics* ; Plant Proteins/physiology* ; Arabidopsis/metabolism* ; Gene Expression Regulation, Plant ; Phylogeny ; Cation Transport Proteins/metabolism* ; Stress, Physiological

Objective:To investigate the clinical characteristics, long-term prognosis and changes of pulmonary function in children with idiopathic pulmonary fibrosis (IPF).Methods:The clinical data, long-term prognosis and changes of pulmonary function of children with IPF admitted to the Department of Pediatric Respiratory Center in Children′s Hospital of Chongqing Medical University from January 2008 to December 2018 were retrospectively analyzed.Results:A total of 28 cases were included, with the median age of 3.9 years (range: 0.5 to 15.7 years). Cough (28 cases, 100.0%), tachypnea (25 cases, 89.3%), cyanosis (19 cases, 67.9%), dyspnea (11 cases, 39.3%), Velcho rales (12 cases, 42.9%), inspiratory three concave sign (11 cases, 39.3%), clubbed fingers and toes (6 cases, 21.4%) and diminished breath sounds (5 cases, 17.9%) were main clinical manifestations.Chest high-resolution computed tomography (HRCT) mainly displayed grid shadow, irregular sac-like light-transparent shadow with ho-neycomb changes and dense shadow, partial (7 cases) pulmonary interstitial emphysema/emphysema/pneumomediastinum.Three cases of lung biopsy showed hyperplasia and consolidation of alveolar space and alveolar septal fibrosis, thickening of alveolar wall and coexistence of new and old lesions.In this group, 4 cases did not receive drug therapy due to other reasons (3 cases abandoned therapy, and 1case died of respiratory and circulatory failure during hospitalization). Twenty-four cases were treated with single or combination of oral Prednisone, N-acetylcysteine and Azithromycin.Eleven cases had improved symptoms when discharged, and 13 cases showed no improvement.Twenty-four cases continued to receive oral medication therapy according to the original protocol.Eight cases were followed up for chest HRCT for 3 months to 4 years, the chest HRCT lesions of 7 cases were similar to before, and those of 1 case increased than before.All cases received telephone follow-up for 2 to 7 years; the maximum duration of medication was 4 years.Twelve cases were lost to follow-up, 7 cases had motion limitation, 3 cases died, and 2 cases had no clinical symptom.Three cases were followed up for pulmonary function for 2 to 3 years, among which 2 cases had pulmonary function decreased than before; 1 case had improvements in forced vital capacity as a percentage of the predicted value and peak expiratory flow as a percentage of the predicted value, but decline in forced expiratory volume in the first se-cond as a percentage of the predicted value.Conclusions:The clinical manifestations of children with IPF are lack of specificity.Chest HRCT is of great value in the diagnosis of IPF and preliminary monitoring of the activity of lesion.In the long-term follow-up, some of cases have improvements in symptoms; pulmonary function mostly decreases, but part of indexes can be improved.