AER1, a major gene conferring resistance to Aphanomyces euteiches in Medicago truncatula.

Aphanomyces euteiches is a major soilborne oomycete pathogen that infects various legume species, including pea and alfalfa. The model legume Medicago truncatula has recently emerged as a valuable genetic system for understanding the genetic basis of resistance to A. euteiches in leguminous crops. The objective of this study was to identify genetic determinants of resistance to a broad host-range pea-infecting strain of A. euteiches in M. truncatula. Two M. truncatula segregating populations of 178 F(5) recombinant inbred lines and 200 F(3) families from the cross F83005.5 (susceptible) x DZA045.5 (resistant) were screened for resistance to A. euteiches. Phenotypic distributions observed suggested a dominant monogenic control of resistance. A major locus associated with resistance to A. euteiches, namely AER1, was mapped by bulk segregant analysis to a terminal end of chromosome 3 in M. truncatula and explained 88% of the phenotypic variation. AER1 was identified in a resistance-gene-rich region, where resistance gene analogs and genes associated with disease resistance phenotypes have been identified. Discovery of AER1 opens up new prospects for improving resistance to A. euteiches in cultivated legumes using a comparative genomics approach.

[Pourfour du Petit syndrome: a rare aetiology of unilateral exophtalmos with mydriasis and lid retraction]. / Le syndrome de Pourfour du Petit : une cause rare d'exophtalmie unilatérale avec mydriase et élargissement de la fente palpébrale.

INTRODUCTION: Pourfour du Petit syndrome, rarely reported, is the opposite of Claude Bernard-Horner syndrome. EXEGESES: A 67 years old female is hospitalised for dysphagia, allowing the discovery of oesophagus carcinoma with mediastinal, pleural and costal extension. The discovery of left unilateral mydriasis associated with exophthalmos and eyelid retraction suggest Pourfour du Petit syndrome; this diagnosis is confirmed by CT-scan, finding pedicular lysis of high dorsal vertebras and intra-canalar tumoral extension. CONCLUSION: Pourfour du Petit syndrome has the same localisation value and the same aetiologies as Claude Bernard-Horner syndrome, but its mechanism proceeds byan exciting lesion of cervical sympathetic nervous system. The recognition of this entity can allow the diagnosis of pathologies that need emergency treatment.