Nectar secretion in excised flowers. V. Effects of indoleacetic acid and sugar supply on distribution of [14C]sucrose in flower tissues and nectar

1978 ◽  
Vol 56 (6) ◽  
pp. 565-571 ◽  
Author(s):  
R. W. Shuel
Keyword(s):  
Indoleacetic Acid ◽  
Sugar Transport ◽  
Reducing Sugar ◽  
Secretory Process ◽  
Percentage Reduction ◽  
Nectar Secretion ◽  
Minimal Growth ◽  
Transport Distance ◽  
Sucrose Solutions ◽  
Secretory Tissue

Movement and distribution of [14C]sucrose was studied in snapdragon flowers cultured on sucrose solutions in relation to the timing and extent of the characteristic reduction of nectar yield by 1AA, the question of whether IAA acts in the nectary cells or by reducing sugar movement to the nectary, and competition for sugar between nectaries and other tissues.There was a 50% reduction in accumulated nectar yield in flowers treated with IAA within 18 h; thereafter, the capacity to secrete nectar was virtually abolished. Within 6 h, IAA caused a significant increase in the incorporation of 14C into protein. Most of the 14C activity lost to nectar in flowers treated with IAA was recovered in the ethanol-soluble materials and protein of the flowers. Radioactivity continued to accumulate in the secretory tissue after secretion had stopped. The percentage reduction in nectar by IAA was not diminished under conditions of minimal growth and sugar transport distance. It was concluded that IAA acts on the secretory process in the nectary cells rather than on movement of sugar to the nectary.The influence of differences in sugar supply appeared mainly in the distribution of 14C activity between peduncles and nectar: as sugar supply was increased, a smaller percentage remained in the peduncles and a larger percentage was secreted. The secretory process competed strongly with floral tissues for sugar even when the latter were undersupplied.

Nectar secretion in excised flowers. VI. Relationship of secretion to protein metabolism

1978 ◽  
Vol 56 (7) ◽  
pp. 833-842 ◽  
Author(s):  
R. W. Shuel ◽  
W. Tsao
Keyword(s):  
Protein Synthesis ◽  
Protein Metabolism ◽  
Indoleacetic Acid ◽  
Sugar Transport ◽  
Adsorptive Capacity ◽  
Total Protein Content ◽  
Nectar Secretion ◽  
Protein Gel ◽  
Relationship Of ◽  
Stimulation Of

The relationship of nectar secretion in snapdragon to protein metabolism, and the influence on both processes of indoleacetic acid (IAA) and to a lesser extent pollination, were both studied. Indoleacetic acid at 5 × 10−4 M appeared to initiate a reorganization in the nectary which led to the stimulation of growth and an early termination of secretion. Two hours after treatment began, incorporation of [14C]uracil into RNA was 60% higher than in controls. A twofold to threefold increase in protein synthesis from [14C]sucrose followed but with no increase and usually a reduction in total nectary protein, despite considerable enlargement of the nectary. These effects suggested a differential action of IAA on protein synthesis and an enhanced degradation of existing protein. Changes in RNA and protein gel electropherograms, and a lowering of the adsorptive capacity of protein in nectary homogenate for [14C]sucrose, were also noted. Actinomycin C, puromycin, and chloramphenicol, like IAA, strongly inhibited secretion but differed from IAA with respect to other effects. None stimulated nectary growth. Actinomycin inhibited synthesis of protein from [14C]sucrose. Puromycin and chloramphenicol increased the amount of protein synthesized from [14C]sucrose but reduced the total protein content. Changes in the nectary following pollination resembled those caused by IAA with respect to RNA and protein gel patterns, stimulation of growth, reduction in tissue protein concentration, and cessation of nectar secretion. It is possible, though not demonstrated, that termination of secretion by IAA and pollination was mediated by changes in proteins associated with sugar transport.

scholarly journals Nectar secretion in a dry habitat: structure of the nectary in two endangered Mexican species of Barkeria (Orchidaceae)

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11874
Author(s):  
Małgorzata Stpiczyńska ◽  
Magdalena Kamińska ◽  
Kevin L. Davies
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Habitat Structure ◽  
Nectar Secretion ◽  
Micro Channels ◽  
Tangential Wall ◽  
Secretory Tissue ◽  
Floral Nectaries ◽  
Structural Adaptations ◽  
Mexican Species

Barkeria scandens and B. whartoniana are endangered, endemic taxa from Mexico. They are epiphytes adapted to dry habitats. Since these plants are xerophytic, their flowers were investigated for structural adaptations to nectar secretion. The flowers of both species are structurally similar, and contrary to most claims for the genus, have functional floral nectaries comprising a nectary chamber and a narrow tubular cuniculus. Nectar is present in both these structures, and contains sugars and lipid-like compounds. The nectary tissue is composed of a single-layered epidermis overlying 1–2 layers of subepidermal secretory parenchyma. The outer tangential wall of the epidermal cells is thick and multi-layered, whereas the cuticle, which often shows blistering, is lamellate and possesses micro-channels. Lipid-like material occurs both between the microfibrils of the cell wall and in the micro-channels. Robust secretory tissue, thick cell walls, and lipid-like nectar components limit nectar evaporation. Moreover, the rigidity of the nectary potentially makes it possible for red-flowered B. scandens to switch from entomophily to ornithophily.

Sugar absorption and secretion by winter flounder intestine

1981 ◽  
Vol 240 (5) ◽  
pp. G392-G400
Author(s):  
R. J. Naftalin ◽  
A. Kleinzeller
Keyword(s):  
Sugar Transport ◽  
Winter Flounder ◽  
Transport Systems ◽  
Secretory Process ◽  
Free Sugar ◽  
Pseudopleuronectes Americanus ◽  
Experimental Conditions ◽  
Sugar Absorption ◽  
Net Flux ◽  
Secretory System

Transport of sugars by winter flounder (Pseudopleuronectes americanus) intestine has been examined, and the following observations have been made. 1) No net absorption of D-galactose was found in controls; however, mucosally applied 0.1 mM phlorizin stimulated the mucosal-serosal flux with net sugar secretion. 2) Net absorption of methyl glycosides was inhibited by D-galactose, 0.1 mM ouabain, and phlorizin (without induction of secretion). 3) Net secretion of 2-deoxy-D-galactose was found without cellular accumulation of free sugar. The secretory process had a Km of 10 mM and was inhibited by serosally applied 0.1 mM phloretin, bilateral replacement of Ringer Na+ by choline, serosal ouabain, and D-galactose. 4) No net absorption or secretion of 2-deoxy-D-glucose was found with a variety of experimental conditions. 5) At least two active transport systems for sugars appear to be operative in the flounder intestine: a conventional Na+-dependent sugar transport system across the brush border that allows net absorption and a Na+-dependent secretory system that apparently also operates across the mucosal border. Because D-galactose is transported by both systems, there is no net flux of this sugar. Several possible models for the net secretory system are discussed.

Improvement of Daptomycin Yield by Overexpression of ATP-Binding Cassette (ABC) Transport Proteins Genes of Daptomycin Gene Cluster

2013 ◽  
Vol 295-298 ◽  
pp. 164-168
Author(s):  
Guang Hai Yu ◽  
Yu Tao Min ◽  
Yuan Sen Hu ◽  
Yan Li Yin ◽  
Liang Huang
Keyword(s):  
Sugar Transport ◽  
Dry Weight ◽  
Transport Proteins ◽  
Reducing Sugar ◽  
Atp Binding ◽  
Positive Role ◽  
Sugar Utilization ◽  
Abc Transport ◽  
Daptomycin Production ◽  
Atp Binding Cassette

The effects of the genes of ORF53-55, which code ATP-binding cassette (ABC) transport proteins, on daptomycin production were investigated by overexpression. The yield of daptomycin was promoted significantly when either of the genes of ORF53, ORF54 or ORF55 was overexpressed individually or by a combined manner. The results above suggested that the ORF53, ORF54 and ORF55 genes had positive cooperativity in the biosynthesis of daptomycin. The dry weight and sugar utilization of HP-ORF53-55 is significantly improved as compared with the LC-54-16. Based on these results, it was speculated that the genes of ORF 53, 54 and 55 may play an important positive role in the process of reducing sugar transport, which enhanced the cell growth and daptomycin biosynthesis.

scholarly journals Structure of trichomatous nectaries in flowers of Lonicera kamtschatica (Sevast.) Pojark.

2012 ◽  
Vol 61 (1) ◽  
pp. 13-26 ◽  
Author(s):  
Elżbieta Weryszko-Chmielewska ◽  
Małgorzata Bożek
Keyword(s):  
Electron Microscopy ◽  
Corolla Tube ◽  
Nectar Secretion ◽  
Apical Portion ◽  
Transmission Electron ◽  
Secretory Tissue ◽  
Floral Nectaries ◽  
Subcuticular Space ◽  
Lateral Walls ◽  
Scanning Electron

The structure of the floral nectaries of <i>Lonicera kamtschatica</i> was examined using light microscopy, scanning electron microscopy and transmission electron microscopy. Nectariferous tissues are located in the lower portion of the corolla tube. It was found that the secretory tissue of the nectary was composed of two layers of epidermal formations: short papillae and about 3x longer unicellular trichomes. They cover the adaxial surface of a small spur. Nectar secretion takes place through the apical portion of the trichomes and papillae. The cell wall of the upper part of the trichome has protuberances participating in nectar transfer to the subcuticular space which reaches large dimensions. The lateral walls of the trichomes are saturated with cutin. The papillae have much thicker walls than the trichomes. In the papillae, there are no wall protuberances. Less secretion accumulates in the subcuticular cavities of the papillae than in the trichomes.

A T.E.M. study of mouse mammary epithelial cell secretory differentiation cultured on collagen and Matrigel

1991 ◽  
Vol 49 ◽  
pp. 188-189
Author(s):  
W.N. Bentham ◽  
V. Rocha
Keyword(s):  
Cell Culture ◽  
Mammary Epithelial ◽  
Secretory Process ◽  
Cell Culture System ◽  
Protein Maturation ◽  
Cell Culture Techniques ◽  
Culture Techniques ◽  
Mouse Mammary Epithelial Cell ◽  
Secretory Differentiation

It has been an interest of our lab to develop a mammary epethelial cell culture system that faithfully duplicates the in vivo condition of the lactating gland. Since the introduction of collagen as a matrix on which cells are cultivated other E.C.M. type matrices have been made available and are used in many cell culture techniques. We have previously demonstrated that cells cultured on collagen and Matrigel do not differentiate as they do in vivo. It seems that these cultures often produce cells that show a disruption in the secretory process. The appearance of large ribosomal studded vesicles, that specifically label with antibody to casein, suggest an interruption of both protein maturation and secretion at the E.R. to golgi transition. In this report we have examined cultures on collagen and Matrigel at relative high and low seeding densities and compared them to cells from the in vivo condition.

Interaction effect of rootstocks on gas exchange parameters, biochemical changes and nutrientstatus in Sauvignon Blanc winegrapes

2014 ◽  
Vol 3 (3) ◽  
pp. 218-225
Author(s):  
R. G. Somkuwar ◽  
M. A. Bhange ◽  
A. K. Upadhyay ◽  
S. D. Ramteke
Keyword(s):  
Biochemical Characterization ◽  
Reducing Sugar ◽  
Wine Grape ◽  
Gas Exchange Parameters ◽  
Food Material ◽  
Total Carbohydrates ◽  
Salt Creek ◽  
Grape Varieties ◽  
Photosynthetic Activities

SauvignonBlanc wine grape was characterized for their various morphological, physiological and biochemical parameters grafted on different rootstocks. Significant differences were recorded for all the parameters studied. The studies on vegetative parameters revealed that the rootstock influences the vegetative growth thereby increasing the photosynthetic activities of a vine. The highest photosynthesis rate was recorded in 140-Ru grafted vine followed by Fercal whereas the lowest in Salt Creek rootstock grafted vines.The rootstock influenced the changes in biochemical constituents in the grafted vine thereby helping the plant to store enough food material. Significant differences were recorded for total carbohydrates, proteins, total phenols and reducing sugar. The vines grafted on1103-Pshowed highest carbohydrates and starch followed by 140-Ru,while the least amount of carbohydrates were recorded in 110-R and Salt Creek grafted vines respectively.Among the different rootstock graft combinations, Fercal showed highest amount of reducing sugar, proteins and phenols, followed by 1103-P and SO4, however, the lowest amount of reducing sugar, proteins and phenols were recorded with 110-R grafted vines.The vines grafted on different rootstocks showed changes in nutrient uptake. Considering this, the physico-biochemical characterization of grafted vine may help to identify particularrootstocks combination that could influence a desired trait in commercial wine grape varieties after grafting.

Biochemical Profiles of Various Fresh Extracts of Gnaphalium polycaulon Pers

2017 ◽  
Vol 9 (04) ◽  
Author(s):  
Shanmugapriya K. ◽  
T. Murugan ◽  
Thayumanavan Tha
Keyword(s):  
Biochemical Analysis ◽  
South India ◽  
Standard Procedure ◽  
Research Work ◽  
Reducing Sugar ◽  
Total Lipids ◽  
Total Proteins ◽  
Total Carbohydrates ◽  
Biochemical Profiles ◽  
First Time

Medicinal plants plays a significant role in the pharmaceutical industry. In present scenario, the need is to explore, identify and utilize this new medicinal plant on one hand and, on the other, to help conserve the existing but threatened species of rare medicinal plant.This present research work was carry out for the first time in South India to analyse and estimate the biochemical profiles of various extracts of fresh parts of Gnaphalium polycaulon pers., plant. The biochemical composition such as total carbohydrates, total proteins, total lipids, total phenols, cholesterol, total chlorophylls and reducing sugar, sterols were estimated using the standard procedure in fresh plant material.The biochemical analysis of Gnaphalium polycaulon plant showed the presence of various phytochemicals. The results of the present study supplement the usage of the studied plant which possesses several bioactive compounds and used as food and also as medicine.The results of present studies demonstrated that Gnaphalium polycaulon plant could be a sourceof valuable information and a guideline for the scientists, researchers in India and also all over the world

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