scholarly journals Reserve metabolism of stored and germinated Araucaria angustifolia seeds

2019 ◽  
Vol 41 ◽  
pp. e42707
Author(s):  
Cristhyane Garcia Araldi ◽  
Cileide Maria Medeiros Coelho
Keyword(s):  
Recalcitrant Seeds ◽  
Araucaria Angustifolia ◽  
Southern Brazil ◽  
Mature Embryos ◽  
Embryo Tissue ◽  
Biochemical Analyses ◽  
Cold Chamber ◽  
Early Developmental ◽  
Hydrolysis Of ◽  
Mature Seeds

Germination metabolism of recalcitrant seeds of Araucaria angustifolia is activated in storage, which complicates the seeds conservation and utilization. This study aimed to identify the changes in the reserve metabolites of A. angustifolia seeds throughout storage in order to understand the processes of hydrolysis caused by germination metabolism. Mature seeds were harvested in southern Brazil and stored in an ambient environment and cold chamber conditions. Biochemical analyses were performed for embryos and megagametophytes from seeds stored for 0, 15, 30, 45, and 90 days. Due to seeds being in advanced germination in storage, they were evaluated at 90 days in different early developmental categories: I – seeds with mature embryos, II – seeds with embryos showing apparent elongation along the embryonic axis, and III – seeds with root protrusion. Higher contents of carbohydrate, protein, and amino acids were observed in embryos compared to megagametophytes, and these metabolites were decreased after onset of germination, especially in the embryo tissue. Mobilization of metabolites in megagametophytes would probably increase in later stages of germination. It is suggested that such alterations are not due to deterioration of reserve components, but instead are based on seed metabolism, which remains active after harvest with hydrolysis of metabolites providing energy for germination.

Mitotic Activity Dynamics in Recalcitrant Seeds Acer sachharinum during Maturation and Germination

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 479c-479
Author(s):  
L. Kozeko ◽  
V. Troyan ◽  
L. Musatenko
Keyword(s):  
Cell Division ◽  
Mitotic Activity ◽  
Quiescent State ◽  
Activity Levels ◽  
Recalcitrant Seeds ◽  
Mature Embryos ◽  
Before And After ◽  
Orthodox Seeds ◽  
Mature Seeds ◽  
Activity Dynamics

In orthodox seeds the cell division within the embryo meristems arrests during maturation at embryo moisture content (MC) 65% to 47%, and the maturation completion and transition of seeds to quiescent state occurs at MC about 10%. The arrest of cycling happens asynchronously in different meristematic tissues during desiccation: first in shoot and then in root. The aim of this work was to define a mitotic activity dynamics in recalcitrant seeds with the high MC at maturation end and the absence of quiescent state characteristic of it. The object was seeds of Acer saccharinum, using widely for planting of greenery in Kiev city. The mitotic activity was determined in 0.5 mm of the embryo root pole (RP) and 0.5 mm of the shoot pole with embryo leaves (SP). The A. sachharinum seeds completed them maturation at MC 53% (FW basis). During maturation the mitotic index (MI) in RP decreased from 3.2% in immature seeds (at embryos MC 80%) to 0 in mature seeds and in SP–from 5.4% to 3.3%, respectively. Cell division in SP arrested by dehydration of mature embryos to MC 46% by PEG 6000 (30%). The seeds lost viability by desiccation to MC 34%. The mature seeds were able to germinate immediately after abscission. During seed germination the cell division reactived in RP and increased in SP already before root protrusion. In plantlets 10–15 mm long the MI increased to 8% in RP and 12% in SP. Thus, the strategy of immediate germination of recalcitrant A. sachharinum seeds includes a preservation of cell division in SP of mature embryos, in contrast with orthodox seeds, and high mitotic activity levels in meristems of germinating embryos before and after root protrusion.

scholarly journals Recognition of protein-linked glycans as a determinant of peptidase activity

2017 ◽  
Vol 114 (5) ◽  
pp. E679-E688 ◽  
Author(s):  
Ilit Noach ◽  
Elizabeth Ficko-Blean ◽  
Benjamin Pluvinage ◽  
Christopher Stuart ◽  
Meredith L. Jenkins ◽  
...  
Keyword(s):  
Posttranslational Modifications ◽  
Peptide Bond ◽  
Peptidase Activity ◽  
Peptide Bonds ◽  
Crystallographic Structures ◽  
Covalently Linked ◽  
Biochemical Analyses ◽  
Life On Earth ◽  
Glycoprotein Degradation ◽  
Hydrolysis Of

The vast majority of proteins are posttranslationally altered, with the addition of covalently linked sugars (glycosylation) being one of the most abundant modifications. However, despite the hydrolysis of protein peptide bonds by peptidases being a process essential to all life on Earth, the fundamental details of how peptidases accommodate posttranslational modifications, including glycosylation, has not been addressed. Through biochemical analyses and X-ray crystallographic structures we show that to hydrolyze their substrates, three structurally related metallopeptidases require the specific recognition of O-linked glycan modifications via carbohydrate-specific subsites immediately adjacent to their peptidase catalytic machinery. The three peptidases showed selectivity for different glycans, revealing protein-specific adaptations to particular glycan modifications, yet always cleaved the peptide bond immediately preceding the glycosylated residue. This insight builds upon the paradigm of how peptidases recognize substrates and provides a molecular understanding of glycoprotein degradation.

scholarly journals Effect of substrate formulations on seedlings of Araucaria angustifolia (Bertol.) Kuntz, a critically endangered species from Southern Brazil

2020 ◽  
Vol 6 (3) ◽  
pp. 239-248
Author(s):  
Leandro Marcolino Vieira ◽  
Erik Nunes Gomes ◽  
Jéssica De Cássia Tomasi ◽  
Valdeci Constantino ◽  
Antônio Carlos Vargas Motta ◽  
...  
Keyword(s):  
Endangered Species ◽  
Critically Endangered ◽  
Araucaria Angustifolia ◽  
Southern Brazil ◽  
Critically Endangered Species

Araucaria angustifolia, vulgarmente conhecida como araucária ou pinheiro do Paraná, é uma espécie de planta ameaçada de extinção, nativa do sul do Brasil. O cultivo desta espécie é uma abordagem importante para reduzir o desmatamento assegurando a geração de renda. O presente estudo teve como objetivo avaliar os efeitos de diferentes formulações de substrato no crescimento, qualidade e teores de clorofila de mudas de araucária em um sistema conjugado substrato/recipiente, como uma abordagem para promover a propagação e o cultivo da espécie. As sementes foram semeadas em quatro composições diferentes de substrato: F73 (casca de pínus, fibra de casca de coco, fertilizante de liberação lenta [FLL] e fertilizantes fosfatados), F55 (casca de pínus, fibra de casca de coco [em maior proporção que em F73], FLL e fertilizantes fosfatados), T55 (casca de pínus, turfa nacional, FLL e fertilizantes fosfatados) e CC55 (casca de pínus, turfa de esfagno, palha de arroz, FLL e fertilizantes fosfatados). As mudas foram mantidas em uma área de viveiro em um sistema conjugado substrato/recipiente, com irrigação manual. Após 180 dias da semeadura, as mudas foram avaliadas quanto à altura, diâmetro de coleto, áreas foliares e radiculares, massa seca de brotações e raízes e teores de clorofilas a, b e clorofilas totais. O quociente de robustez e o índice de qualidade de Dickson (IQD) também foram calculados com base nas variáveis ​​biométricas. Os substratos F73 e CC55 promoveram maior crescimento de altura e diâmetro de coleto em comparação com outros substratos. Outras variáveis ​​relacionadas ao crescimento e qualidade das mudas e aos níveis de clorofila não diferiram em função dos substratos. A massa seca de raiz e massa seca total foram correlacionadas positivamente com o IQD. O diâmetro do coleto apresentou alta correlação positiva com a altura, a massa seca da parte aérea e a massa seca total das mudas de A.angustifolia.

scholarly journals VEGETATIVE RESCUE AND CUTTINGS PROPAGATION OF Araucaria angustifolia (Bertol.) Kuntze

2015 ◽  
Vol 39 (1) ◽  
pp. 93-104 ◽  
Author(s):  
Ivar Wendling ◽  
Gilvano Ebling Brondani
Keyword(s):  
Butyric Acid ◽  
Coniferous Tree ◽  
Araucaria Angustifolia ◽  
Southern Brazil ◽  
Wood Production ◽  
Main Trunk ◽  
Old Trees ◽  
Upper Third ◽  
Environmental Importance

Brazilian pine or araucaria (Araucaria angustifolia) is a coniferous tree with great economic, social and environmental importance in southern Brazil, being exploited for both wood production and for its edible pine nuts. However, no efficient cloning techniques are available and, therefore, the purpose of this study was to evaluate the effectiveness of vegetative rescue methods for cuttings propagation of the species. Shoots/cuttings were generated in two ways: 26 years old trees underwent coppicing and 20 years old trees had the primary branches on the upper third of crown pruned at 2, 20 and 50 cm from the main trunk. Orthotropic shoots were rooted after application of indole-3-butyric acid (IBA) at 0, 2, 4 and 6 g.L-1. Coppicing produced 47 cuttings per plant with 90% orthotropic shoots, while pruning resulted in 182 cuttings per plant with 44% orthotropic shoots. Rooting success indexes were low with no influence of IBA, although they are slightly superior to the ones available in the literature for the species, ranging from 12 to 30% for the coppice shoots and from 0 to 28% for the branches shoots. We conclude that both vegetative rescue techniques are viable and have potentially important applications. Coppicing is recommended for the propagation aiming the production of wood, while shoots derived from the side branches of the crown are more appropriate for seeds orchards formation.

scholarly journals Remobilization and fate of sulphur in mustard

2019 ◽  
Vol 124 (3) ◽  
pp. 471-480 ◽  
Author(s):  
Priyakshee Borpatragohain ◽  
Terry J Rose ◽  
Lei Liu ◽  
Bronwyn J Barkla ◽  
Carolyn A Raymond ◽  
...  
Keyword(s):  
Developmental Stages ◽  
Storage Proteins ◽  
Growth And Yield ◽  
Growth Stages ◽  
Secondary Source ◽  
Early Developmental ◽  
Mature Seeds ◽  
Senesced Leaves ◽  
Net Fluxes ◽  
Yield Penalty

Abstract Background and Aims Sulphur (S) is an essential macronutrient involved in numerous metabolic pathways required for plant growth. Crops of the plant family Brassicaceae require more S compared with other crops for optimum growth and yield, with most S ultimately sequestered in the mature seeds as the storage proteins cruciferin and napin, along with the unique S-rich secondary metabolite glucosinolate (GSL). It is well established that S assimilation primarily takes place in the shoots rather than roots, and that sulphate is the major form in which S is transported and stored in plants. We carried out a developmental S audit to establish the net fluxes of S in two lines of Brassica juncea mustard where seed GSL content differed but resulted in no yield penalty. Methods We quantified S pools (sulphate, GSL and total S) in different organs at multiple growth stages until maturity, which also allowed us to test the hypothesis that leaf S, accumulated as a primary S sink, becomes remobilized as a secondary source to meet the requirements of GSL as the dominant seed S sink. Key Results Maximum plant sulphate accumulation had occurred by floral initiation in both lines, at which time most of the sulphate was found in the leaves, confirming its role as the primary S sink. Up to 52 % of total sulphate accumulated by the low-GSL plants was lost through senesced leaves. In contrast, S from senescing leaves of the high-GSL line was remobilized to other tissues, with GSL accumulating in the seed from commencement of silique filling until maturity. Conclusion We have established that leaf S compounds that accumulated as primary S sinks at early developmental stages in condiment type B. juncea become remobilized as a secondary S source to meet the demand for GSL as the dominant seed S sink at maturity.

scholarly journals Structural insights into TSC complex assembly and GAP activity on Rheb

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Huirong Yang ◽  
Zishuo Yu ◽  
Xizi Chen ◽  
Jiabei Li ◽  
Ningning Li ◽  
...  
Keyword(s):  
Tuberous Sclerosis ◽  
Catalytic Mechanism ◽  
Coiled Coil ◽  
Small Gtpase ◽  
Dimerization Domain ◽  
Gtp Hydrolysis ◽  
Complex Assembly ◽  
Complex Functions ◽  
Biochemical Analyses ◽  
Hydrolysis Of

AbstractTuberous sclerosis complex (TSC) integrates upstream stimuli and regulates cell growth by controlling the activity of mTORC1. TSC complex functions as a GTPase-activating protein (GAP) towards small GTPase Rheb and inhibits Rheb-mediated activation of mTORC1. Mutations in TSC genes cause tuberous sclerosis. In this study, the near-atomic resolution structure of human TSC complex reveals an arch-shaped architecture, with a 2:2:1 stoichiometry of TSC1, TSC2, and TBC1D7. This asymmetric complex consists of two interweaved TSC1 coiled-coil and one TBC1D7 that spans over the tail-to-tail TSC2 dimer. The two TSC2 GAP domains are symmetrically cradled within the core module formed by TSC2 dimerization domain and central coiled-coil of TSC1. Structural and biochemical analyses reveal TSC2 GAP-Rheb complimentary interactions and suggest a catalytic mechanism, by which an asparagine thumb (N1643) stabilizes γ-phosphate of GTP and accelerate GTP hydrolysis of Rheb. Our study reveals mechanisms of TSC complex assembly and GAP activity.

scholarly journals ASPECTOS PRODUTIVOS E COMERCIAIS DO PINHÃO NO ESTADO DO PARANÁ

FLORESTA ◽  
2002 ◽  
Vol 32 (2) ◽  
Author(s):  
Anadalvo Juazeiro Dos Santos ◽  
Néder Maciel Corso ◽  
Gílson Martins ◽  
Eduardo Bittencourt
Keyword(s):  
Rio Grande ◽  
Araucaria Angustifolia ◽  
Southern Brazil ◽  
Rio Grande Do Sul ◽  
Santa Catarina ◽  
Edible Seed ◽  
Marketing Chain

Este artigo tem por objetivo analisar aspectos produtivos e de comercialização do pinhão, semente da árvore conhecida vulgarmente como Pinheiro do Paraná (Araucária angustifolia (Bert.) O Kuntze). Esta espécie vegetal de porte arbóreo ocorre na região Sul e Sudeste do Brasil, principalmente nos Estados do Rio Grande do Sul, Santa Catarina e Paraná. Do ponto de vista metodológico foi primeiramente realizado um levantamento de dados econômicos sobre este produto nas instituições públicas do Estado do Paraná. A partir destes dados foram calculadas a Margem Bruta e o Markup de Comercialização. Também foi construído o fluxograma que apresenta os diversos elos que compõe a cadeia extrativa deste Produto Florestal Não Madeirável. Os resultados obtidos indicam que a maior parte da lucratividade no interior desta cadeia é apropriada pelos intermediários. Técnicas de conservação e industrialização devem ser desenvolvidas para promover a comercialização e uso do pinhão em outras épocas do ano, além da estação de produção. Isto tornaria o preço de mercado mais atraente incentivando a sua extração e comercialização. PRODUCTIVE AND COMMERCIAL ASPECT OF PINHÃO IN PARANA STATE Abstract This paper intends to give a marketing prime in the study of the pinhão, an edible seed from Parana-pine (Araucaria angustifolia (Bert.) O Kuntze).This species occurs in Southern Brazil, mainly along the States of Rio Grande do Sul, Santa Catarina and Parana.This study concentrated firstly in the agregation of data from publics institucions of Parana State. Secondly, it carries out the calculus of the index of gross commercialization margins and markup of commercialization. It also builds a flow concerning the various levels composing the marketing chain. Results obtained point out that the majority of rentability is apropriate for intermediary also the industralization techniques should be developed in order to promote the commercialization and use of pinhão in other periods of the year, besides the season of production. Addicionaly, there should be better prices for de producers to incentive the activity

scholarly journals Comparison of seedling growth among three co-occurring varieties of Araucaria angustifolia (Bertol.) Kuntze under greenhouse conditions

2010 ◽  
Vol 24 (2) ◽  
pp. 567-570 ◽  
Author(s):  
André Luiz Coutinho ◽  
Lúcia Rebello Dillenburg
Keyword(s):  
Seedling Recruitment ◽  
Lateral Roots ◽  
The Other ◽  
Initial Growth ◽  
Seed Color ◽  
Araucaria Angustifolia ◽  
Southern Brazil ◽  
Main Root ◽  
Positive Effects ◽  
Mass Allocation

Araucaria angustifolia (Bertol.) Kuntze is a tall, long-lived tree species, which grows as an emergent tree in the araucaria forests of southern Brazil. Four varieties have been described for this species, and three of them were selected for this study: "angustifolia" (the type variety), "caiova" and "indehiscens". These are co-occurring varieties that differ in external seed color and timing of seed maturation. The purpose of this study was to compare the initial growth of plants originated from seeds of these three varieties, in order to test the hypothesis that these varieties also differ in the initial growth of their seedlings. Seeds were collected from a single forest location, and 60 plants per variety were grown in pots for a period of 244 days. The "angustifolia" variety accumulated significantly more mass (both in shoot and root) than the other two, but the three varieties did not differ in mass allocation between shoot and root and between lateral roots and the main root. The greater growth of the type variety may help explain its greater natural abundance, since attaining a larger size will have positive effects on seedling recruitment and survival.

scholarly journals The Sec14-like phosphatidylinositol transfer proteins Sec14l3/SEC14L2 act as GTPase proteins to mediate Wnt/Ca2+ signaling

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Bo Gong ◽  
Weimin Shen ◽  
Wanghua Xiao ◽  
Yaping Meng ◽  
Anming Meng ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Calcium Release ◽  
Tissue Formation ◽  
Transfer Protein ◽  
Phosphatidylinositol Transfer ◽  
Biochemical Analyses ◽  
Canonical Wnt ◽  
Phosphatidylinositol Transfer Proteins ◽  
G Protein Coupled ◽  
Hydrolysis Of

The non-canonical Wnt/Ca2+ signaling pathway plays important roles in embryonic development, tissue formation and diseases. However, it is unclear how the Wnt ligand-stimulated, G protein-coupled receptor Frizzled activates phospholipases for calcium release. Here, we report that the zebrafish/human phosphatidylinositol transfer protein Sec14l3/SEC14L2 act as GTPase proteins to transduce Wnt signals from Frizzled to phospholipase C (PLC). Depletion of sec14l3 attenuates Wnt/Ca2+ responsive activity and causes convergent and extension (CE) defects in zebrafish embryos. Biochemical analyses in mammalian cells indicate that Sec14l3-GDP forms complex with Frizzled and Dishevelled; Wnt ligand binding of Frizzled induces translocation of Sec14l3 to the plasma membrane; and then Sec14l3-GTP binds to and activates phospholipase Cδ4a (Plcδ4a); subsequently, Plcδ4a initiates phosphatidylinositol-4,5-bisphosphate (PIP2) signaling, ultimately stimulating calcium release. Furthermore, Plcδ4a can act as a GTPase-activating protein to accelerate the hydrolysis of Sec14l3-bound GTP to GDP. Our data provide a new insight into GTPase protein-coupled Wnt/Ca2+ signaling transduction.

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