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Plener L.,French National Institute for Agricultural Research | Manfredi P.,French National Institute for Agricultural Research | Valls M.,Facultat de Biologia | Genin S.,French National Institute for Agricultural Research
Journal of Bacteriology | Year: 2010

The ability of Ralstonia solanacearum to cause disease in plants depends on its type III secretion system (T3SS). The expression of the T3SS and its effector substrates is coordinately controlled by a regulatory cascade, at the bottom of which is HrpB. Transcription of the hrpB gene is activated by a plant-responsive regulator named HrpG, which is a master regulator of a wide array of pathogenicity functions in R. solanacearum. We have identified in the genome of strain GMI1000 a close paralog of hrpG (83% overall similarity at the protein level) that we have named prhG. Despite this high similarity, the expression pattern of prhG is remarkably different from that of hrpG: prhG expression is activated after growth of bacteria in minimal medium but not in the presence of host cells, while hrpG expression is specifically induced in response to plant cell signals. We provide genetic evidence that prhG is a transcriptional regulator that, like hrpG, controls the expression of hrpB and the hrpB-regulated genes under minimal medium conditions. However, the regulatory functions of prhG and hrpG are distinct: prhG has no influence on hrpB expression when the bacteria are in the presence of plant cells, and transcriptomic profiling analysis of a prhG mutant revealed that the PrhG and HrpG regulons have only one pathogenicity target in common, hrpB. Functional complementation experiments indicated that PrhG and HrpG are individually sufficient to activate hrpB expression in minimal medium. Rather surprisingly, a prhG disruption mutant had little impact on pathogenicity, which may indicate that prhG has a minor role in the activation of T3SS genes when R. solanacearum grows parasitically inside the plant. The cross talk between pathogenicity regulatory proteins and environmental signals described here denotes that an intricate network is at the basis of the bacterial disease program. Copyright © 2010, American Society for Microbiology. All Rights Reserved. Source

Ferrer-Suay M.,University of Barcelona | Selfa J.,University of Valencia | Villemant C.,CNRS Systematics, Biodiversity and Evolution Institute | Pujade-Villar J.,Facultat de Biologia
Zoosystema | Year: 2015

Charipinae Dalla Torre & Kieffer, 1910 material collected during the ATBI of the Mercantour National Park in the Alpes-Maritimes (France) has been studied. Based on the study of 362 specimens, 35 species in four genera have been identified from: 23 Alloxysta Förster, 1869; 10 Phaenoglyphis Förster, 1869; one Apocharips Fergusson, 1986 and one Dilyta Förster, 1869. Of these, 19 species are recorded from France for the first time: Alloxysta abdera Fergusson, 1986; Alloxysta arcuata (Kieffer, 1902); Alloxysta brachycera Hellén, 1963; Alloxysta brevis (Thomson, 1962); Alloxysta fracticornis (Thomson, 1862); Alloxysta mullensis (Cameron, 1883); Alloxysta pilipennis (Hartig, 1840); Alloxysta postica (Hartig, 1841); Alloxysta proxima Belizin, 1962; Apocharips trapezoidea (Hartig, 1841); Phaenoglyphis abbreviata (Thomson, 1877); Phaenoglyphis americana Baker, 1896; Phaenoglyphis calverti Andrews, 1978; Phaenoglyphis evenhuisi Pujade-Villar & Paretas-Martínez, 2006; Phaenoglyphis fuscicornis (Thomson, 1877); Phaenoglyphis gutierrezi Andrews, 1978; and Phaenoglyphis longicornis (Hartig, 1840). All the Charipinae species identified are briefly described and compared with one another. Three new species are described and illustrated in detail: Alloxysta alpina Ferrer-Suay & Pujade-Villar, n. sp.; Alloxysta franca Ferrer-Suay & Pujade-Villar, n. sp. and Alloxysta pilae Ferrer-Suay, n. sp. A key to the species of Charipinae known from the Mercantour National Park is provided. © Publications scientifiques du Muséum national d'Histoire naturelle, Paris. Source

Sinev A.Y.,Moscow State University | Alonso M.,Facultat de Biologia | Miracle M.R.,University of Valencia | Sahuquillo M.,University of Valencia
Zootaxa | Year: 2012

A study of several populations of the West Palaearctic endemic Alona azorica Frenzel & Alonso, 1988 reveals the existence of a sibling-species. Alona azorica s. str. is confined to the Azores and the Atlantic part of West Iberia; Alona anastasia sp. nov. inhabits temporary ponds in Mediterranean Iberia and other West Mediterranean regions. It differs by size, by the morphology of the head shield and head pores, and by the shape of the male postabdomen. Both species belong to the pulchella-group of Alona s. lato. Alona anastasia sp. nov. population dynamics and seasonal variation in body size in the province of Valencia (Spain) are also studied. Copyright © 2012 Magnolia Press. Source

Alonso M.,Facultat de Biologia | Ventura M.,CSIC - Center for Advanced Studies of Blanes | Ventura M.,University of Barcelona
Zootaxa | Year: 2013

A new species of Phallocryptus Biraben 1951 (Branchiopoda, Anostraca) from Mongolia is described. Phallocryptus tse-rensodnomi sp. nov. is close to P. spinosa (Milne-Edwards 1840), but both morphological and molecular analyses (Cyto-chrome Oxidase I, COI) indicate that they represent separate species. Most relevant differential features of the new species include: (1) frontal appendage provided with small ventral conical outgrowths; (2) second antennamere evenly curved, sickle-shaped; (3) distal fleshy process on labrum evenly curved forwards and tapering; (4) short stout acute spine-like projections present at each side of basal portion of gonopods; (5) female second antennae shorter and wider than in P. spinosa, tapering. Based on morphological comparisons the new species appears to be a Mongolian endemic, although some genotypes of presumed P. spinosa from Africa are similar to the new species, suggesting P. tserensodnomi might have a wider distribution. Copyright © 2013 Magnolia Press. Source

Kotov A.A.,RAS Severtsov Institute of Ecology | Alonso M.,Facultat de Biologia
Zootaxa | Year: 2010

We describe two new species of Leydigia Kurz, 1875 (Chydoridae, Cladocera) from Spain. L. (Neoleydigia) iberica sp. nov. has a series of traits rarely observed in well-studied species of the subgenus L. (Neoleydigia), and never in this combination: (1) PP distance large; (2) numerous, low hillocks on preanal margin of postabdomen; (3) numerous setae in lateral fascicles on postabdomen, plus distalmost and next setae subequal in size; (4) sensory seta shifted to distal end of antenna I, but not so markedly as in L. microps; (5) fully setulated basal segment of distalmost scraper on limb III; (6) 5 setae on exopodite III. L (N.) korovchinskyi sp. nov. has seven setae on limb III exopodite, characteristic for only two species of the subgenus L. (Neoleydigia) Kotov, 2009, namely L. (N.) propinqua and L. (N.) microps, but the former differs from both latter taxa in: (1) absence of a "coarse" striation; (2) rounded apex of labral keel and (3) longer setae 3-4 of exopodite III. At this moment, each species was found in a single locality. Both species are rare and seem endemic of Iberian Peninsula (but may be found in some surrounded Mediterranean territories); they could be regarded as relicts sensu Korovchinsky (2006). © 2010 Magnolia Press. Source

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