Leafy gall formation by Rhodococcus fascians.
Rhodococcus fascians infects a wide range of plants, initiating the formation of leafy galls that consist of centers of shoot amplification and shoot growth inhibition. R. fascians is an epiphyte but it also can establish endophytic populations. Bacterial signals involved in symptom development initiate de novo cell division and shoot meristem formation in differentiated tissues. The R. fascians signals exert activities that are distinct from mere cytokinin effects, and the evidence points to a process that adopted cytokinin biosynthetic enzymes to form derivatives with unique activity. Genes implicated in leafy gall formation are located on a linear plasmid and are subject to a highly controlling, complex regulatory network, integrating autoregulatory compounds and environmental signals. Leafy galls are considered as centers with specific metabolic features, a niche where populations of R. fascians experience a selective advantage. Such "metabolic habitat modification" might be universal for gall-inducing bacteria.
Goethals
K
K
Vakgroep Moleculaire Genetica & Departement of Plantengenetica, Vlaams Interuniversitair Instituut voor Biotechnologie (VIB), Universiteit Gent, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium. kogoe@gengenp.rug.ac.be
Vereecke
D
D
Jaziri
M
M
Van Montagu
M
M
Holsters
M
M
D019684:Magnoliopsida / Q000378:metabolism / Q000382:microbiology*; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism / Q000382:microbiology; D010941:Plant Tumors / Q000235:genetics / Q000382:microbiology*; D012240:Rhodococcus / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D014774:Virulence / Q000235:genetics
D010937:Plant Growth Regulators