Gravity susception by buoyancy: floating lipid globules in sporangiophores of Phycomyces

@article{Grolig2003GravitySB,
  title={Gravity susception by buoyancy: floating lipid globules in sporangiophores of Phycomyces},
  author={Franz Grolig and Heinz Herkenrath and T. Pumm and Andrea Gross and Paul Galland},
  journal={Planta},
  year={2003},
  volume={218},
  pages={658-667}
}
To elucidate the mechanisms of gravity susception that operate in the sporangiophore of Phycomyces blakesleeanus, we characterized the function and topography of a large apical complex of lipid globules. Stage-1 sporangiophores (without sporangium) possess a roughly spherical complex of 100–200 large lipid globules whose center is localized 110 μm below the apex. The complex of lipid globules (CLG) is rather stable and is kept in place by positioning forces that resist centrifugal accelerations… Expand
Gravireception of the sporangiophore of Phycomyces blakesleeanus
Abstract The sporangiophore of the zygomycete Phycomyces blakesleeanus displays negative gravitropism that manifests with a latency of some 5–15 min after stimulation. Sporangiophores possess anExpand
Gravisusception by buoyancy: a mechanism ubiquitous among fungi?
TLDR
In the vegetative sporangiophore of the zygomycete Phycomyces blakesleeanus some 200 large lipid globules form a conspicious spherical complex which is positioned in a dense mesh of filamentous actin about 100 μm below the growing tip of the apex, meeting basic physical criteria for a possible function of gravisusception. Expand
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TLDR
Additional phenomena pertaining to gravireception, specifically adherence to the novel exponential law and non-adherence to the classical resultant law of gravitropism, were for the first time investigated for Phycomyces. Expand
Actin cytoskeleton and organelle movement in the sporangiophore of the zygomycete Phycomyces blakesleeanus.
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Optospectroscopic Detection of Primary Reactions Associated with the Graviperception of Phycomyces. Effects of Micro- and Hypergravity1
TLDR
The graviperception of sporangiophores of the fungus Phycomyces blakesleeanus involves gravity-induced absorbance changes (GIACs) that represent primary responses of gravitropism, and these GIACs have a latency of about 20 ms or shorter and are thus the fastest graviresponses ever measured for fungi, protists, and plants. Expand
Graviresponses in fungi and slime molds
The analysis of gravisensing in fungi has not yet proceeded as far as in other systems, such as sensory cells for maintenance of equilibrium in crustaceans and vertebrates, Chara rhizoids or plantExpand
Gravitaxis in Euglena.
TLDR
It has been proven that this flagellate possesses a physiological gravireceptor and an active orientation for Euglena gracilis, and the threshold for gravity perception was determined and physiological, biochemical and molecular components of the signal transduction chain have been identified. Expand
Ca2+ and H+ Ion Fluxes near the Surface of Gravitropically Stimulated Phycomyces Sporangiophore
  • B. Živanović
  • Chemistry, Medicine
  • Annals of the New York Academy of Sciences
  • 2005
TLDR
The single‐celled fungus Phycomyces blakesleeanus forms vertically oriented sporangiophores from hyphae, which display a negative gravitropic response, and noninvasive H+ and Ca2+ ion‐selective microelectrode measurements reveal direction of ion fluxes depended on developmental stage of sporang iophores and changed with gravistimulation. Expand
Photomorphogenesis and Gravitropism in Fungi
TLDR
There are indications that other fungi, even other ascomycetes, have molecular mechanisms for photoreception that are different from the one in N. crassa, and it is becoming clear that there are limits to the use of N.crassa as a model for fungal photobiology. Expand
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