• Klíčová slova
• GROWTH/in adolescence *, HAND/in adolescence *,
• MeSH
• fyziologické jevy * MeSH
• lidé MeSH
• mladiství MeSH
• ruka * MeSH
• růst * MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• Publikační typ
• časopisecké články MeSH

In a world of accelerating changes in environmental conditions driving tree growth, tradeoffs between tree growth rate and longevity could curtail the abundance of large old trees (LOTs), with potentially dire consequences for biodiversity and carbon storage. However, the influence of tree-level tradeoffs on forest structure at landscape scales will also depend on disturbances, which shape tree size and age distribution, and on whether LOTs can benefit from improved growing conditions due to climate warming. We analyzed temporal and spatial variation in radial growth patterns from ~5000 Norway spruce (Picea abies [L.] H. Karst) live and dead trees from the Western Carpathian primary spruce forest stands. We applied mixed-linear modeling to quantify the importance of LOT growth histories and stand dynamics (i.e., competition and disturbance factors) on lifespan. Finally, we assessed regional synchronization in radial growth variability over the 20th century, and modeled the effects of stand dynamics and climate on LOTs recent growth trends. Tree age varied considerably among forest stands, implying an important role of disturbance as an age constraint. Slow juvenile growth and longer period of suppressed growth prolonged tree lifespan, while increasing disturbance severity and shorter time since last disturbance decreased it. The highest age was not achieved only by trees with continuous slow growth, but those with slow juvenile growth followed by subsequent growth releases. Growth trend analysis demonstrated an increase in absolute growth rates in response to climate warming, with late summer temperatures driving the recent growth trend. Contrary to our expectation that LOTs would eventually exhibit declining growth rates, the oldest LOTs (>400 years) continuously increase growth throughout their lives, indicating a high phenotypic plasticity of LOTs for increasing biomass, and a strong carbon sink role of primary spruce forests under rising temperatures, intensifying droughts, and increasing bark beetle outbreaks.

• Klíčová slova
• basal area increment, dendroecology, forest dynamics, generalized linear mixed models, growth trends, growth-mortality tradeoff, maximum lifespan,
• MeSH
• dlouhověkost MeSH
• klimatické změny MeSH
• lesy MeSH
• smrk * fyziologie   MeSH
• stromy * MeSH
• Publikační typ
• časopisecké články MeSH

The shape of the maternal pericarp affects cereal grain mass and yield. Pericarp growth was analysed by magnetic resonance imaging (MRI), revealing topological maps of mobile water in developing pericarp of barley (Hordeum vulgare) and displaying tissue regions actively elongating in specific temporal-spatial patterns. Correlation analysis of MRI signals and growth rates reveals that growth in length is mediated by dorsal and also lateral rather than ventral regions. Growth in thickness is related to ventral regions. Switching from dorsal to ventral growth is associated with differential expression of axial regulators of the HD-ZipIII and Kanadi/Ettin types, and NPH3 photoreceptors, suggesting light-mediated auxin re-distribution. Auxin increases with the highest levels in the basal pericarp at 6 days after fertilization (DAF), together with transcriptionally up-regulated auxin transport and signalling. Gibberellin biosynthesis is transcriptionally up-regulated only later, and levels of bioactive gibberellins increase from 7 to 13 DAF, with higher levels in ventral than dorsal regions. Differential gene expression related to cell expansion indicates genes related to apoplast acidification, wall relaxation, sugar cleavage, water transport, and cell wall biosynthesis. Candidate genes potentially involved in pericarp extension are distinguished by their temporal expression, representing potential isoforms responsible for dorsal-mediated early growth in length or ventral-mediated late growth in thickness.

• Klíčová slova
• Auxin, barley pericarp, cell expansion, directed growth, gibberellic acid, grain length, growth dynamics, magnetic resonance imaging, transcript profiling.,
• MeSH
• gibereliny metabolismus   MeSH
• ječmen (rod) genetika   růst a vývoj   metabolismus   MeSH
• kyseliny indoloctové metabolismus   MeSH
• magnetická rezonanční tomografie MeSH
• regulace genové exprese u rostlin * MeSH
• regulátory růstu rostlin metabolismus   MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• semena rostlinná genetika   růst a vývoj   metabolismus   MeSH
• stanovení celkové genové exprese MeSH
• vývojová regulace genové exprese MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• gibereliny MeSH
• kyseliny indoloctové MeSH
• regulátory růstu rostlin MeSH
• rostlinné proteiny MeSH

Climate warming may stimulate growth and reproduction in cold-adapted plants, but also reduce their performance due to warming-induced drought limitation. We tested this theory using a unique experiment with the alpine forb Rumex alpinus. We examined how climate warming over the past four decades affected its annual rhizome growth, leaf production and flowering, and whether responses varied between alpine, subalpine and montane populations. Before the period of accelerated warming in the 1970s and 1980s, the primary limitation on growth had been cold temperatures and short growing seasons. Increased summer temperatures in the 1990s and 2000s enhanced rhizome growth and leaf production, but not flowering. Alpine and subalpine plants profit more than montane plants, currently producing three times longer annual rhizome increments and twice as many leaves as 40 yr ago, and achieving nearly the same values as montane plants. During the warmest 2005-2015 period, growth became contingent on summer precipitation and began to decrease across all populations, likely due to an increasing water shortage in dense monospecific stands. Warming releases plants from cold limitations but induces water shortage. Rumex alpinus exceeds its thermal optimum and becomes water-limited as the climate warms. Our results suggest that warming-induced responses in alpine plants will not be one-sided shifts to higher growth and reproduction, but rather multidimensional and spatiotemporally variable.

• Klíčová slova
• climate warming, clonal plants, elevation gradient, flowering, growth, long-term response, rhizome, spatiotemporal dynamics,
• MeSH
• klimatické změny * MeSH
• květy * MeSH
• roční období MeSH
• rozmnožování MeSH
• teplota MeSH
• vývoj rostlin MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Global climate change is having significant effects on plant growth patterns and mountain plants can be particularly vulnerable to accelerated warming. Rising temperatures are releasing plants from cold limitation, such as at high elevations and latitudes, but can also induce drought limitation, as documented for trees from lower elevations and latitudes. Here we test these predictions using a unique natural experiment with Himalayan alpine shrub Rhododendron anthopogon and its growth responses to changing climate over a large portion of its latitudinal and elevational ranges, including steep precipitation and temperature gradients. We determined growth dynamics during the last three decades, representing period of accelerated warming, using annual radial growth increments for nine populations growing on both wet and warm southern localities and drier and cold northern localities in the Himalayas along elevation gradients encompassing the lower and upper species range limits. A significant growth increase over past decades was observed after controlling for confounding effect of shrub age and microsites. However, the magnitude of increase varied among populations. Particularly, populations situated in the lower elevation of the northernmost (cold and dry) locality exhibited most substantial growth enhancement. The relationship between growth variability and climate varied among populations, with the populations from the coldest location displaying the strongest responsiveness to increasing minimum temperatures during July. Minimum temperatures of April and August were the most important factor limiting the growth across most populations. Potential warming-induced drought limitation had no significant impact on growth variation in any part of the species geographic range. Overall, our findings indicate that plant growth is continuously increasing in recent decades and growth-climate relationships are not consistent across populations, with populations from the coldest and wettest localities showing stronger responses. The observed patterns suggest that dwarf-shrubs benefit from ongoing warming, leading to increased shrubification of high elevation alpine ecosystems.

• Klíčová slova
• Alpine ecosystems, Annual growth rings, Climate Change, Dwarf shrub, Growth sensitivity,
• MeSH
• ekosystém * MeSH
• globální oteplování * MeSH
• klimatické změny MeSH
• rostliny MeSH
• stromy MeSH
• teplota MeSH
• Publikační typ
• časopisecké články MeSH

Possibilities of conducting longitudinal human growth studies are very limited, since it is necessary to monitor the probands for a long time. Another problem can be a loss of data currency, and the small size of the final sample. The solution can be a follow-up semi-longitudinal observation. This research is drawn up as a short longitudinal monitoring of 1925 children (990 boys, 935 girls), aged 6-15 years, at 20 elementary schools in four regions of the Czech Republic, which has been conducted at the same time. Data of repeatedly examined probands of a wide age range were acquired in a short time period. With the help of a linear regression model with mixed effect, the growth velocity curves of 12 somatic traits have been obtained. The timing, intensity and duration of separate growth spurts have been observed, as well as the mutual location of both points of growth velocity, local maxima and minima, and points of the maximal acceleration and deceleration. The results demonstrate that the velocity of characters with variable growth dynamics (skin-fold thicknesses, circumferences of limbs) - contrary to characters with regular growth velocity - have a higher number of partial growth spurts and an opposite course. In the period of separate growth velocity, peaks of somatic characters with regular growth dynamics reach points of partial local minima. In comparison to previous longitudinal studies of body height growth dynamics, the shift of both the beginning and the peak of boys' and girls' pubertal spurt, to a lower age can be found.

• MeSH
• antropometrie MeSH
• dítě MeSH
• končetiny MeSH
• lidé MeSH
• longitudinální studie MeSH
• mladiství MeSH
• růst * MeSH
• sexuální faktory MeSH
• tělesná hmotnost MeSH
• tělesná výška MeSH
• tloušťka kožní řasy MeSH
• vývoj dítěte * MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH

The delineation of protein-lipid interfaces is essential for understanding the mechanisms of various membrane-associated processes crucial to plant development and growth, including signalling, trafficking, and membrane transport. Due to their highly dynamic nature, the precise characterization of lipid-protein interactions by experimental techniques is challenging. Molecular dynamics simulations provide a powerful computational alternative with a spatial-temporal resolution allowing the atomistic-level description. In this review, we aim to introduce plant scientists to molecular dynamics simulations. We describe different steps of performing molecular dynamics simulations and provide a broad survey of molecular dynamics studies investigating plant protein-lipid interfaces. Our aim is also to illustrate that combining molecular dynamics simulations with artificial intelligence-based protein structure determination opens up unprecedented possibilities for future investigations of dynamic plant protein-lipid interfaces.

• Klíčová slova
• Integral membrane protein, membrane, molecular dynamics simulations, peripheral membrane protein, protein–lipid interactions, structural modelling,
• MeSH
• rostlinné proteiny * metabolismus   chemie   MeSH
• rostliny metabolismus   MeSH
• simulace molekulární dynamiky * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• rostlinné proteiny * MeSH

Pollen germination and subsequent pollen tube elongation are essential for successful land plant reproduction. These processes are achieved through well-documented activation of membrane trafficking and cell metabolism. Despite this, our knowledge of the dynamics of cellular phospholipids remains scarce. Here we present the turnover of the glycerolipid composition during the establishment of cell polarity and elongation processes in tobacco pollen and show the lipid composition of pollen plasma membrane-enriched fraction for the first time. To achieve this, we have combined several techniques, such as lipidomics, plasma membrane isolation, and live-cell microscopy, and performed a study with different time points during the pollen germination and pollen tube growth. Our results showed that tobacco pollen tubes undergo substantial changes in their whole-cell lipid composition during the pollen germination and growth, finding differences in most of the glycerolipids analyzed. Notably, while lysophospholipid levels decrease during germination and growth, phosphatidic acid increases significantly at cell polarity establishment and continues with similar abundance in cell elongation. We corroborated these findings by measuring several phospholipase activities in situ. We also observed that lysophospholipids and phosphatidic acid are more abundant in the plasma membrane-enriched fraction than that in the whole cell. Our results support the important role for the phosphatidic acid in the establishment and maintenance of cellular polarity in tobacco pollen tubes and indicate that plasma membrane lysophospholipids may be involved in pollen germination.

• Klíčová slova
• lipidomics, phosphatidic acid, phospholipid, plasma membrane, pollen, pollen tube, tip growth, tobacco,
• Publikační typ
• časopisecké články MeSH

FGF2 is secreted from cells by an unconventional secretory pathway. This process is mediated by direct translocation across the plasma membrane. Here, we define the minimal molecular machinery required for FGF2 membrane translocation in a fully reconstituted inside-out vesicle system. FGF2 membrane translocation is thermodynamically driven by PI(4,5)P2-induced membrane insertion of FGF2 oligomers. The latter serve as dynamic translocation intermediates of FGF2 with a subunit number in the range of 8-12 FGF2 molecules. Vectorial translocation of FGF2 across the membrane is governed by sequential and mutually exclusive interactions with PI(4,5)P2 and heparan sulfates on opposing sides of the membrane. Based on atomistic molecular dynamics simulations, we propose a mechanism that drives PI(4,5)P2 dependent oligomerization of FGF2. Our combined findings establish a novel type of self-sustained protein translocation across membranes revealing the molecular basis of the unconventional secretory pathway of FGF2.

• Klíčová slova
• Fibroblast Growth Factor 2, Unconventional protein secretion, biochemistry, biophysics, human, oligomerization, phosphoinositide, protein translocation across membranes, reconstitution with purified components, structural biology,
• MeSH
• fibroblastový růstový faktor 2 metabolismus   MeSH
• fosfatidylinositol-4,5-difosfát metabolismus   MeSH
• heparitinsulfát metabolismus   MeSH
• membránové transportní proteiny metabolismus   MeSH
• multimerizace proteinu * MeSH
• sekreční vezikuly metabolismus   MeSH
• simulace molekulární dynamiky MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fibroblastový růstový faktor 2 MeSH
• fosfatidylinositol-4,5-difosfát MeSH
• heparitinsulfát MeSH
• membránové transportní proteiny MeSH

A growing bacterial colony is not an amorphous mass but is a dynamic and differentiated system. It may appear chaotic in the details of its structure but it can be accurately described by simple models for fractal geometry. As Benoit Mandelbrot said: 'Surprise, simple rules can generate rich structures'.

• MeSH
• Bacillus růst a vývoj   ultrastruktura   MeSH
• biologické modely MeSH
• buněčné dělení MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH