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Bendra schema – cheminis valdymas. Signalų poveikis. Skirtinga reakcija į tą patį neuromediatorių. atsiminti tarpląstelinį signalą. Ląstelė gali atsiminti kai kuriuos signalus (Ca 2+ ) po to, kai signalas jau išnyko.
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atsiminti tarpląstelinį signalą • Ląstelė gali atsiminti kai kuriuos signalus (Ca2+) po to, kai signalas jau išnyko. • Ca2+ aktyvuota protein-kinazė fosforilina save ir kitus baltymus. Autofosforilinimas leidžia išlaikyti protein-kinazės aktyvumą ir po to, kai signalas išnyksta – Ca2+ koncentracija grįžta į normą. • Trumpalaikiai tarpląsteliniai signalai daugialąsčiuose organizmuose dažnai sukelia gerokai ilgiau trunkančius pokyčius organizmų vystymesi. Tai vyksta per besiaktyvuojančius atminties mechanizmus, genų transkripcijos lygyje.
Viduląsteliniai jungikliai Phosphorylation and dephosphorylation via protein kinases and phosphatases. Thereby stimulating or inhibiting the activities GAPs inactivate G-protein; GEFs activates G-protein; GDIs(guanine nucleotide-dissociation inhibitors) maintain the G-protein inactive.
Kaip NO valdo The same mechanism also explains the mechanism of action of the chemical nitroglycerin. The drug sildenafil, sold under the trade name Viagra, is an inhibitor of a cyclic GMP-specific phosphodiesterase that normally catalyzes the breakdown of cyclic GMP. The carbon monoxide(CO) acts as a cellular messenger to stimulate the production of cGMP by stimulating G-cyclase.
Over 250 ecdysteroid analogs have been identified so far in plants
Long-term resistance, or systemic acquired resistance (SAR), • SAR involves communication of the damaged tissue with the rest of the plant using plant hormones such as : • jasmonic acid, • ethylene, • abscisic acid • salicylic acid. • The reception of the signal leads to global changes within the plant, which induce genes that protect from further pathogen intrusion, including enzymes involved in the production of phytoalexins. • Often, if jasmonates or ethylene (both gaseous hormones) is released from the wounded tissue, neighboring plants also manufacture phytoalexins in response. • For herbivores, common vectors for disease, these and other wound response aromatics seem to act as a warning that the plant is no longer edible. • Also, in accordance with the old adage, "an enemy of my enemy is my friend," the aromatics may alert natural enemies of the plant invaders to the presence thereof.