Search results for "Glomus"
showing 10 items of 59 documents
Gènes fongiques liés au calcium impliqués dans la mycorhize à arbuscules
2012
Fluctuations in intracellular (Ca2+) calcium levels generate signaling events and regulate different cellular processes. Whilst the implication of Ca2+ in plant cell responses during arbuscular mycorrhiza (AM) interactions is well documented, nothing is known about the regulation or role of this secondary meesenger in the fungal symbiont. The molecular basis of fungal calcium homeostasis in the AM symbiosis was analyzed by investigating the expression of Ca2+-related fungal genes. In a first study, G. mosseae genes putatively encoding a MAP3k-like protein kinase (Gm2) and a P-type ATPase (Gm152) were investigated. Both Ca2+-related genes were up-regulated by A. sinicum root exudates, sugges…
Fungal genes related to calcium homeostasis and signalling are upregulated in symbiotic arbuscular mycorrhiza interactions
2012
Fluctuations in intracellular calcium levels generate signalling events and regulate different cellular processes. Whilst the implication of Ca2+ in plant responses during arbuscular mycorrhiza (AM) interactions is well documented, nothing is known about the regulation or role of this secondary messenger in the fungal symbiont. The spatio-temporal expression pattern of putatively Ca2+-related genes of Glomus intraradices BEG141 encoding five proteins involved in membrane transport and one nuclear protein kinase, was investigated during the AM symbiosis. Expression profiles related to successful colonization of host roots were observed in interactions of G. intraradices with roots of wild-ty…
Signalling between arbuscular mycorrhizal fungi and plants: Identification of a gene expressed during early interactions by differential RNA display …
2002
Although there is evidence for an interplay of signalling/recognition events at different stages during plant/fungal interactions in arbuscular mycorrhiza, the nature of signalling molecules and signal perception/transduction processes are so far unknown. Virtually nothing is known of molecular interactions during initial contact between arbuscular mycorrhizal symbionts, but plant mutants which limit fungal development to these first steps (myc-1) provide proof of the involvement of plant genes. One such pea mutant (P2) has been used to investigate gene expression during early plant-fungal interactions by differential RNA display. Partial transcriptome analysis has indicated frequent simila…
Structural and functional genomics of symbiotic arbuscular mycorrhizal fungi.
2004
The absorbing organs (roots, rhizomes) of nearly all terrestrial plant families host an intimate symbiotic association, called a mycorrhiza, with specialized functional groups of soil fungi. The most common type of root symbiosis is the arbuscular mycorrhiza where soil fungi interact with a tremendous diversity of plant species, including many forest trees and agricultural, horticultural, and fruit crops (Gianinazzi et al., 2002). The fungi involved are very ancient microorganisms compared to other true fungi. Fossil data and molecular phylogenetic analyses indicate that their origin dates back to the Ordovician-Devonian era some 460 to 400 million years ago (Remy et al., 1994; Redecker et …
Expression of p11 and Heteromeric TASK Channels in Rat Carotid Body Glomus Cells and Nerve Growth Factor–differentiated PC12 Cells
2020
Psychological stress activates the hypothalamus, augments the sympathetic nervous output, and elevates blood pressure via excitation of the ventral medullary cardiovascular regions. However, anatomical and functional connectivity from the hypothalamus to the ventral medullary cardiovascular regions has not been fully elucidated. We investigated this issue by tract-tracing and functional imaging in rats. Retrograde tracing revealed the rostral ventrolateral medulla was innervated by neurons in the ipsilateral dorsomedial hypothalamus (DMH). Anterograde tracing showed DMH neurons projected to the ventral medullary cardiovascular regions with axon terminals in contiguity with tyrosine hydroxyl…
Hearing results after hypotympanotomy for glomus tympanicum tumors.
2011
We postulate, that glomus tympanicum tumors (GTTs) may be safely removed without interference with the ossicular chain via a hypotympanotomy approach.Prospective, nonrandomized anatomic and clinical study.Tertiary referral center.All 17 patients between 1989 and 2009 with GTTs without involvement of the lumen of the jugular bulb.We used a modified hypotympanotomy approach. Our technique is a modification of the one first published by Shambaugh (1955). Pure-tone audiograms were performed in all patients. Preoperative and postoperative audiograms were modeled in a linear mixed model evaluating hearing threshold for air and bone conduction and air-bone gap at 500, 1,000, 2,000, and 3,000 Hz. I…
Impact of water stress on plant water relations, growth and mycorhization of Acacia tortilis ssp. raddiana: Interactions of the stress severity and d…
2010
Mycorrhizae are commonly reported to improve drought resistance of the host plant. Investigating factors controlling the plant-resistance strategy to water stress can however lead to a suitable management of mycorrhizal plants under drought. Here, we focused on the impact of interactions of the AM fungal species and water stress severity and duration on mycorrhizal Acacia tortilis ssp. raddiana in terms of plant growth, mycorhization and water relations. We used three Glomus species, which were G. mosseae, G. deserticola and G. intraradices. We applied three watering regimes that were maximum water holding non-stress regime, mild-severe water stress and severe water stress. Measurements wer…
An O-2-sensitive glomus cell-stem cell synapse induces carotid body growth in chronic hipoxia
2014
Neural stem cells (NSCs) exist in germinal centers of the adult brain and in the carotid body (CB), an oxygen-sensing organ that grows under chronic hypoxemia. How stem cell lineage differentiation into mature glomus cells is coupled with changes in physiological demand is poorly understood. Here, we show that hypoxia does not affect CB NSC proliferation directly. Rather, mature glomus cells expressing endothelin-1, the O2-sensing elements in the CB that secrete neurotransmitters in response to hypoxia, establish abundant synaptic-like contacts with stem cells, which express endothelin receptors, and instruct their growth. Inhibition of glomus cell transmitter release or their selective des…
Miega artērijas audzēju ķirurģiska ārstēšana Latvijā no 2010. līdz 2015.gadam
2016
Ievads: Miega artēriju audzēji (MAA) ir reti, lēni augoši un labi apasiņoti neiroendokrīni veidojumi, kuru izcelsme ir miega artērijas bifurkācijas līmenī esošās paraganglionārās šūnas. Mērķis: Pētījuma mērķis bija izpētīt MAA pacientus Latvijā pēdējo piecu gadu laikā, veicot demogrāfisku, kā arī ārstēšanās iznākumu analīzi. Materiāli un metodes: Tika veikta retrospektīva analīze, caurskatot pacientu slimības vēstures no 2010. līdz 2015. gadam Paula Stradiņa Klīniskās Universitātes slimnīcā, kurā esošais asinsvadu ķirurģijas centrs ir vadošais Latvijā, kurā ārstē MAA. Pētījuma ietvaros pacienti tika arī uzaicināti uz duplex ultrasonogrāfiju apsekošanai. Rezultāti: Kopumā 10 pacientiem tika …
Detection of a plant enzyme exhibiting chlorogenate-dependant caffeoyltransferase activity in methanolic extracts of arbuscular mycorrhizal tomato ro…
2012
When Glomus intraradices-colonised tomato roots were extracted in methanol at 6 degrees C, chlorogenic acid (5-caffeoylquinic acid), naturally present in the extract, was slowly converted by transesterification into methyl caffeate. The progress of the reaction could be monitored by HPLC. The reaction only occurred when the ground roots were left in contact with the hydro-alcoholic extract and required the presence of 15-35% water in the mixture. When the roots were extracted in ethanol, chlorogenic acid was transformed to ethyl caffeate in the same conditions. The reaction was also detected in Glomus mosseae-colonised tomato root extracts. It was also detectable in non-mycorrhizal root ext…