THE SECRETORY CYCLE OF DIONAEA MUSCIPULA ELLIS

Abstract

SUMMARYAutoradiography has been used to track the path of secretion in the digestive glands of Dionaea muscipula. Neither the dictyosomes nor dictyosomal vesicles appear to be involved, but radiolabel is lost rapidly from the endoplasmic reticulum and small osmiophilic vacuoles directly into the cell wall. Radiolabel is subsequently lost from the large osniiophilic vacuoles and accumulates in the small vacuoles. The effects of colchicine and cytochalasin B are complex. Both decrease the enzymatic activity of the secretion, but not the protein content, suggesting effects on the synthesis and discharge of secretion not directed against micro tubules or microfilaments. It is proposed that the discharge of secretion occurs by direct fusion of ER to the plasmalemma or via vesicles and vacuoles derived from the ER.

In touch: plant responses to mechanical stimuli

“…Smaller insects, perhaps not worth the energy of further trapping and digestion, may be free to escape through the bars, but larger insects struggle to get free (Darwin, 1893). The insect's further agitation and excretion of nitrogenous compounds, although not always necessary for complete closure (Fagerberg & Allain, 1991), may enhance the subsequent sealing of the lobes around the doomed animal and the secretion of acids and digestive enzymes that kill and digest the nascent meal (Robins & Juniper, 1980). Spatially complex and dynamic changes in cell expansion among distinct tissue layers and sublobe domains effect each stage of the trap closure (Fagerberg & Allain, 1991).…”

3D electron tomographic and biochemical analysis of ER, Golgi and trans Golgi network membrane systems in stimulated Venus flytrap (Dionaea muscipula) glandular cells

“…ER, Golgi, vacuoles and plasma membranes [ 4 , 5 , 7 , 12 , 13 ]. The anthocyanin pigment-containing vacuoles were also shown to accumulate proteins and lipidic compounds and to change their morphology upon induction [ 4 , 12 , 14 ]. In cells treated with [ 14 C] leucine, autoradiography and biochemical experiments demonstrated the presence of newly synthesized proteins in the ER, Golgi, vacuoles and the cell wall [ 6 , 14 ].…”

“…The anthocyanin pigment-containing vacuoles were also shown to accumulate proteins and lipidic compounds and to change their morphology upon induction [ 4 , 12 , 14 ]. In cells treated with [ 14 C] leucine, autoradiography and biochemical experiments demonstrated the presence of newly synthesized proteins in the ER, Golgi, vacuoles and the cell wall [ 6 , 14 ]. Based on these studies it was concluded that proteins synthesized in the endoplasmic reticulum (ER) were delivered both to the vacuoles and to the cell surface.…”

Metabolism of [15N]glycine and [13C]glycine by Dionaea muscipula studied by gas chromatography‐mass spectrometry

“…Various aspects of the trapping and digestion process have been examined in detail, including the factors controlling trap narrowing (Lichtner & Williams, 1977), secretion production (Robins, 1976;Robins & Juniper, 1980a) and composition (Rea, 1982;Robins & Juniper, 19806, f), and the uptake and absorption of nutrients by the trap (Rea & Whatley, 1983;Robins & Juniper, 1980^. We have used gas chromatography-mass spectrometry (GC-MS) in order to study the metabolism of [^^CJglycine and ['-''NJglycine in plants of Dionaea muscipula. Such studies have not been previously performed with Dionaea, although the metabolism by Drosera plants of compounds absorbed from insects labelled with ''^N (Dixon, Pate & Bailey, 1980) and ' "^S (Chandler & Anderson, 1976) has been reported.…”