scholarly journals Sexual and Apogamous Species of Woodferns Show Different Protein and Phytohormone Profiles

2021 ◽  
Vol 12 ◽  
Author(s):  
Helena Fernández ◽  
Jonas Grossmann ◽  
Valeria Gagliardini ◽  
Isabel Feito ◽  
Alejandro Rivera ◽  
...  
Keyword(s):  
Ribosome Biogenesis ◽  
Experimental System ◽  
Plant Reproduction ◽  
Ultra Performance Liquid Chromatography ◽  
Zeatin Riboside ◽  
Fern Gametophyte ◽  
Isopentenyl Adenine ◽  
Physiological Approach ◽  
Isopentenyl Adenosine ◽  
Peculiar Case

The gametophyte of ferns reproduces either by sexual or asexual means. In the latter, apogamy represents a peculiar case of apomixis, in which an embryo is formed from somatic cells. A proteomic and physiological approach was applied to the apogamous fern Dryopteris affinis ssp. affinis and its sexual relative D. oreades. The proteomic analysis compared apogamous vs. female gametophytes, whereas the phytohormone study included, in addition to females, three apogamous stages (filamentous, spatulate, and cordate). The proteomic profiles revealed a total of 879 proteins and, after annotation, different regulation was found in 206 proteins of D. affinis and 166 of its sexual counterpart. The proteins upregulated in D. affinis are mostly associated to protein metabolism (including folding, transport, and proteolysis), ribosome biogenesis, gene expression and translation, while in the sexual counterpart, they account largely for starch and sucrose metabolism, generation of energy and photosynthesis. Likewise, ultra-performance liquid chromatography-tandem spectrometry (UHPLC-MS/MS) was used to assess the levels of indol-3-acetic acid (IAA); the cytokinins: 6-benzylaminopurine (BA), trans-Zeatine (Z), trans-Zeatin riboside (ZR), dyhidrozeatine (DHZ), dyhidrozeatin riboside (DHZR), isopentenyl adenine (iP), isopentenyl adenosine (iPR), abscisic acid (ABA), the gibberellins GA3 and GA4, salicylic acid (SA), and the brassinosteroids: brassinolide (BL) and castasterone (CS). IAA, the cytokinins Z, ZR, iPR, the gibberellin GA4, the brassinosteoids castasterone, and ABA accumulated more in the sexual gametophyte than in the apogamous one. When comparing the three apogamous stages, BA and SA peaked in filamentous, GA3 and BL in spatulate and DHRZ in cordate gametophytes. The results point to the existence of large metabolic differences between apogamous and sexual gametophytes, and invite to consider the fern gametophyte as a good experimental system to deepen our understanding of plant reproduction.

Cytokinin production by the fungi Taphrina cerasi and T. deformans

1974 ◽  
Vol 52 (7) ◽  
pp. 1583-1589 ◽  
Author(s):  
James C. Johnston ◽  
Edward J. Trione
Keyword(s):  
Culture Medium ◽  
Callus Tissue ◽  
Zeatin Riboside ◽  
Cytokinin Activity ◽  
Liquid Media ◽  
Migration Patterns ◽  
Soybean Callus ◽  
Isopentenyl Adenine ◽  
Isopentenyl Adenosine ◽  
Solvent Systems

Cytokinins were released into chemically defined liquid media by cultures of Taphrina cerasi and T. deformans. The presence of the cell-division factors was demonstrated with the soybean callus tissue assay, which is specific for the detection of cytokinins. Paper chromatography in four solvent systems, in conjunction with bioassays, revealed that T. cerasi produced compounds that have migration patterns similar to those of zeatin, zeatin riboside, N6-(Δ2-isopentenyl) adenine, and N6-(Δ2-isopentenyl)adenosine. T. deformans produced compounds with chromatographic properties similar to those of zeatin, zeatin riboside, and a substance(s) the migration of which is correlated with the Rf interval that included the positions of N6-(Δ2-isopentenyl) adenine and its riboside. A third type of cytokinin, the mobility of which differs from those of the cytokinin standards used, was also produced by T. deformans. The total cytokinin activity in cultures of T. cerasi was calculated to be about 2 μg kinetin-equivalents per liter of culture medium, and the amount released by T. deformans was about 4 μg kinetin-equivalents per liter of medium.

scholarly journals Salt Stress-induced Injury is Associated with Hormonal Alteration in Kentucky Bluegrass

HortScience ◽  
2018 ◽  
Vol 53 (1) ◽  
pp. 97-101 ◽  
Author(s):  
Xunzhong Zhang ◽  
Wenli Wu ◽  
Erik H. Ervin ◽  
Chao Shang ◽  
Kim Harich
Keyword(s):  
Salt Stress ◽  
Cell Membrane ◽  
Poa Pratensis ◽  
Membrane Damage ◽  
Kentucky Bluegrass ◽  
Zeatin Riboside ◽  
Cool Season ◽  
Cell Membrane Damage ◽  
Turf Quality ◽  
Isopentenyl Adenosine

Plant hormones play an important role in plant adaptation to abiotic stress, but hormonal responses of cool-season turfgrass species to salt stress are not well documented. This study was carried out to investigate the responses of hormones to salt stress and examine if salt stress-induced injury was associated with hormonal alteration in kentucky bluegrass (KBG, Poa pratensis L.). The grass was grown in a growth chamber for 6 weeks and then subjected to salt stress (170 mm NaCl) for 28 days. Salt stress caused cell membrane damage, resulting in photosynthetic rate (Pn), chlorophyll (Chl), and turf quality decline in KBG. Salt stress increased leaf abscisic acid (ABA) and ABA/cytokinin (CK) ratio; reduced trans-zeatin riboside (ZR), isopentenyl adenosine (iPA), and indole-3-acetic acid (IAA), but did not affect gibberellin A4 (GA4). On average, salt stress reduced ZR by 67.4% and IAA by 58.6%, whereas it increased ABA by 398.5%. At the end of the experiment (day 28), turf quality, Pn, and stomatal conductance (gs) were negatively correlated with ABA and ABA/CK ratio, but positively correlated with ZR, iPA, and IAA. Electrolyte leakage (EL) was positively correlated with ABA and ABA/CK and negatively correlated with ZR, iPA, IAA, and GA4. GA4 was also positively correlated with turf quality and gs. The results of this study suggest that salt stress-induced injury of the cell membrane and photosynthetic function may be associated with hormonal alteration and imbalance in KBG.

Evidence for the Oxidation of N6-(Δ2-Isopentenyl)adenine and N6-(3-Hydroxy-3-methylbutyl)adenine by Xanthine Oxidase

1973 ◽  
Vol 51 (7) ◽  
pp. 1123-1126 ◽  
Author(s):  
B. D. McLennan ◽  
A. Pater
Keyword(s):  
Xanthine Oxidase ◽  
Spectral Data ◽  
Ultraviolet Absorption ◽  
Oxidation Products ◽  
Mass Spectral Data ◽  
Mass Spectral ◽  
Isopentenyl Adenine ◽  
Isopentenyl Adenosine

Two known metabolites of N6-(Δ2-isopentenyl)adenosine, namely N6-(Δ2-isopentenyl)adenine and N6-(3-hydroxy-3-methylbutyl)adenine, have been shown to be oxidized by xanthine oxidase. On the basis of ultraviolet absorption and mass spectral data, the oxidation products, in each case, have been tentatively identified as the 8-hydroxy and 2,8-dihydroxy derivatives.

Mild temperature stress modulates cytokinin content and cytokinin oxidase/dehydrogenase activity in young pea plants

2009 ◽  
Vol 57 (1) ◽  
pp. 33-40 ◽  
Author(s):  
I. Vaseva ◽  
D. Todorova ◽  
J. Malbeck ◽  
A. Travničkova ◽  
I. Machačkova
Keyword(s):  
Low Temperature ◽  
Enzymatic Activity ◽  
Dehydrogenase Activity ◽  
Growth Conditions ◽  
Zeatin Riboside ◽  
Cytokinin Oxidase ◽  
Temperature Stresses ◽  
Isopentenyl Adenine ◽  
Mild Temperature ◽  
Adaptive Reactions

Cytokinin oxidase/dehydrogenase (CKX: EC 1.5.99.12) is able to provide a means for the rapid turnover of its substrate and it has been considered responsible for changes in the cytokinin pool in an adverse environment. Mild temperature stresses (10°C and 33°C average) were applied to young pea plants of two varieties (cvs. Manuela and Scinado) in order to assess the response of the cytokinin pool and CKX activity to altered growth conditions. Both temperature treatments increased the isopentenyl adenine (iP) and isopentenyl adenine riboside (iPR) contents in stressed plants. This trend was far more pronounced in the leaves. Low temperature additionally resulted in elevated cis zeatin riboside ( cis ZR) and CKX activity. Heat did not influence the enzymatic activity in the leaves, while opposing trends were observed in the root-derived CKX activity of the two tested varieties. The data suggest that variance in the temperature provokes adaptive reactions in the cytokinin pool, which is maintained by CKX activity.

N6-(Δ2-isopentenyl)adenosine: hydrolysis by a nucleosidase isolated from Lactobacillus acidophilus cells

1975 ◽  
Vol 21 (5) ◽  
pp. 633-638 ◽  
Author(s):  
J. Hordern ◽  
R. H. Johnson ◽  
B. D. McLennan
Keyword(s):  
Substrate Specificity ◽  
Lactobacillus Acidophilus ◽  
Purine Nucleoside ◽  
Bacterial Enzyme ◽  
Electrophoretic Behavior ◽  
Isopentenyl Adenine ◽  
Isopentenyl Adenosine ◽  
Rapid Conversion

A nucleosidase activity has been isolated from Lactobacillus acidophilus which rapidly hydrolyses N6-(Δ2-isopentenyl)adenosine to its corresponding base, N6-(Δ2-isopentenyl)adenine. The activity can be distinguished from the spleen exzyme (EC. 2.4.2.1), a purine nucleoside transferase, on the basis of its substrate specificity, electrophoretic behavior, and non-dependence on phosphate. The bacterial enzyme hydrolyzes both inosine and isopentenyl adenosine, giving Km values of 63.3 μM and 177 μM respectively. The presence of this enzyme in bacteria accounts for the rapid conversion of the parent nucleoside to isopentenyl adenine, which has been observed in these cells. The enzyme thus assumes importance as one of the catabolic activities available to the cell for metabolizing the cytokinin, N6-(Δ2-isopentenyl)adenosine.

scholarly journals In Vitro Propagation of the Rare and Endangered Grevillea scapigera (Proteaceae)

HortScience ◽  
1992 ◽  
Vol 27 (3) ◽  
pp. 261-262 ◽  
Author(s):  
Eric Bunn ◽  
Kingsley W. Dixon
Keyword(s):  
Shoot Growth ◽  
Adventitious Shoots ◽  
Adventitious Shoot ◽  
Zeatin Riboside ◽  
Multiplication Rate ◽  
Rare And Endangered Species ◽  
Isopentenyl Adenine ◽  
Rare And Endangered

Micropropagation, including adventitious shoot growth from leaf sections, was achieved for Grevillea scapigera (Proteaceae), a rare and endangered species from Western Australia. Shoot tips were initiated on filter paper supports with liquid WPM (Woody Plant Medium) and supplemented with 20 μm zeatin riboside and 2 μm GA3. Shoots were then incubated on WPM solidified with agar and supplemented with 5 μm kinetin and 0.5 μm BA, which produced an approximate 6-fold multiplication rate per month. Up to three adventitious shoots were induced from 0.7-cm2 leaf sections after 6 to 7 weeks on solid 1/2 MS (Murashige and Skoog) medium supplemented with 10 μm BA and 0.5 μm IBA. Shoots, 30 to 50 mm long, were rooted in vivo in a fogged glasshouse under 70% shade using a commerical rooting powder [IBA, 0.1% (w/w)] applied to the base of the shoots. Most (67%) of the shoots treated in this way rooted after 5 weeks. Established, rooted plants have been grown on under glasshouse conditions. Chemical names used: N6-[2-isopentenyl] adenine riboside (zeatin riboside); gibberellic acid (GA3); 6-furfurylaminopurine (kinetin); N-(phenylmethyl)-1H-purine-6-amine (BA); 1-H-indole-3-butyric acid (IBA).

scholarly journals Endogenous auxin and cytokinin contents associated with shoot formation in leaves of pineapple cultured in vitro

2003 ◽  
Vol 15 (2) ◽  
pp. 107-112 ◽  
Author(s):  
Helenice Mercier ◽  
Beatriz Maia Souza ◽  
Jane Elizabeth Kraus ◽  
Regina Mayumi Hamasaki ◽  
Bruno Sotta
Keyword(s):  
Shoot Formation ◽  
Zeatin Riboside ◽  
Strong Increase ◽  
Induction Medium ◽  
Naphthaleneacetic Acid ◽  
Endogenous Auxin ◽  
Isopentenyl Adenine ◽  
Basal Portion ◽  
Shoot Induction Medium

The in vitro culture of pineapple leaves on a shoot induction medium (SIM) results in the formation of protuberances and further development in shoots, and plantlets. The contents of endogenous indoleacetic acid (IAA) and five cytokinins (Cks), N6(2-isopentenyl)adenine (iP), N6(2-isopentenyl)adenosine (iPR), zeatin (Z), zeatin riboside (ZR) and N6-benzyladenine (BA), present in the basal portion of those leaves, were correlated to the organogenic response that occurs over 15 days of culture. The endogenous auxin/cytokinins ratio was lowest on the 3rd day, mainly due to a strong increase in the iP level. It seems that endogenous iP concentration triggered the induction signal for an organogenic response in pineapple leaf bases. The rise in iP content required the presence of BA and a-naphthaleneacetic acid (NAA) in the medium, suggesting that endogenous iP production is regulated in response to these growth regulator uptakes.

Cytokinin effects on pollen embryogenesis in cultured anthers of Hyoscyamus niger

1989 ◽  
Vol 67 (1) ◽  
pp. 247-257 ◽  
Author(s):  
V. Raghavan ◽  
R. Nagmani
Keyword(s):  
Callus Formation ◽  
Generative Cell ◽  
Basal Medium ◽  
Root Apex ◽  
Zeatin Riboside ◽  
Pollen Embryogenesis ◽  
Zygotic Embryogenesis ◽  
Hyoscyamus Niger ◽  
Mineral Salts ◽  
Isopentenyl Adenine

Addition of the cytokinins, benzylaminopurine, N6-Δ-(2-isopentenyl)-adenine, kinetin, zeatin, and zeatin riboside to a basal medium containing mineral salts and sucrose induced characteristic changes in pollen embryogenesis in cultured anthers and anther segments of Hyoscyamus niger. In anthers cultured in media containing 0.01–10.0 mg/L of each cytokinin, there was a progressive delay in the appearance of plantlets outside the anther locule and in the morphology of plantlets formed. Among the cytokinins tested, only zeatin riboside promoted anther efficiency; however, all compounds reduced pollen efficiency by as much as 40–60% of the control even in the lowest concentration tested. The effects of cytokinins were particularly noticeable in the failure of pollen grains to form embryoids by the division of the generative cell and in the decrease in the number of embryoids formed by the division of both generative and vegetative cells. At the morphogenetic level, embryoids formed in media containing cytokinins displayed various abnormalities such as precocious elongation of the root apex, cotyledon expansion, and callus formation on the cotyledons, hypocotyl, and root. During their subsequent growth, calluses induced on embryoids by benzylaminopurine, N6-Δ-(2-isopentenyl)-adenine, zeatin, and zeatin riboside formed somatic embryos that recapitulated stages of zygotic embryogenesis. Globular and heart-shaped embryoids, which did not develop further, were frequently observed on kinetin-induced pollen callus; the callus also regenerated leafy shoots by organogenesis. Addition of adenine to the medium did not have any effect on pollen embryogenesis in cultured anthers of H. niger.

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