Multi-functional T-DNA/Ds tomato lines designed for gene cloning and molecular and physical dissection of the tomato genome.

In order to make the tomato genome more accessible for molecular analysis and gene cloning, we have produced 405 individual tomato (Lycopersicon esculentum) lines containing a characterized copy of pJasm13, a multifunctional T-DNA/modified Ds transposon element construct. Both the T-DNA and the Ds element in pJasm13 harbor a set of selectable marker genes to monitor excision and reintegration of Ds and additionally, target sequences for rare cutting restriction enzymes (I-PpoI, SfiI, NotI) and for site-specific recombinases (Cre, FLP, R). Blast analysis of flanking genomic sequences of 174 T-DNA inserts revealed homology to transcribed genes in 69 (40%), of which about half are known or putatively identified as genes and ESTs. The map position of 140 individual inserts was determined on the molecular genetic map of tomato. These inserts are distributed over the 12 chromosomes of tomato, allowing targeted and non-targeted transposon tagging, marking of closely linked genes of interest and induction of chromosomal rearrangements including translocations or creation of saturation-deletions or inversions within defined regions linked to the T-DNA insertion site. The different features of pJasm13 were successfully tested in tomato and Arabidopsis thaliana, thus providing a new tool for molecular/genetic dissection studies, including molecular and physical mapping, mutation analysis and cloning strategies in tomato and potentially, in other plants as well.

Pulmonary lymphangiomyomatosis. Demonstration of smooth muscle antigens by immunofluorescence technique.

A case is reported of pulmonary lymphangiomyomatosis in 44-year-old woman presenting with progressive exertional dyspnoea, unproductive cough and haemoptysis. The patient showed no symptoms or signs of tuberous sclerosis, a condition often found in association with pulmonary lymphangiomyomatosis. A pulmonary biopsy specimen showed disruption of alveolar septa and fibrosis. Subpleural lymph vessels and pulmonary venules showed cuffs of spindle-shaped cells. The leiomyomatous nature of these cells was evident from their appearance and staining reactions with light microscopy, and the presence of smooth muscle antigens as demonstrated by immunofluorescence technique. Since the lesion is not restricted to lymphatics, but can also be present in blood vessels, the condition may more appropriately be designated as pulmonary angiomyomatosis.