scholarly journals A Talk between Flavonoids and Hormones to Reorient the Growth of Gymnosperms

2021 ◽  
Vol 22 (23) ◽  
pp. 12630
Author(s):  
Luis Morales-Quintana ◽  
Patricio Ramos
Keyword(s):  
Wood Quality ◽  
Wood Formation ◽  
Differential Growth ◽  
Gravitropic Response ◽  
Auxin Distribution ◽  
Key Factor ◽  
Genetic Mechanisms ◽  
Forestry Industry ◽  
Auxin Flux ◽  
Molecular Aspects

Plants reorient the growth of affected organs in response to the loss of gravity vector. In trees, this phenomenon has received special attention due to its importance for the forestry industry of conifer species. Sustainable management is a key factor in improving wood quality. It is of paramount importance to understand the molecular and genetic mechanisms underlying wood formation, together with the hormonal and environmental factors that affect wood formation and quality. Hormones are related to the modulation of vertical growth rectification. Many studies have resulted in a model that proposes differential growth in the stem due to unequal auxin and jasmonate allocation. Furthermore, many studies have suggested that in auxin distribution, flavonoids act as molecular controllers. It is well known that flavonoids affect auxin flux, and this is a new area of study to understand the intracellular concentrations and how these compounds can control the gravitropic response. In this review, we focused on different molecular aspects related to the hormonal role in flavonoid homeostasis and what has been done in conifer trees to identify molecular players that could take part during the gravitropic response and reduce low-quality wood formation.

scholarly journals Auxin methylation is required for differential growth inArabidopsis

2018 ◽  
Vol 115 (26) ◽  
pp. 6864-6869 ◽  
Author(s):  
Mohamad Abbas ◽  
Jorge Hernández-García ◽  
Stephan Pollmann ◽  
Sophia L. Samodelov ◽  
Martina Kolb ◽  
...  
Keyword(s):  
Gene Expression ◽  
Auxin Transport ◽  
Polar Auxin Transport ◽  
Asymmetric Distribution ◽  
Loss Of Function ◽  
Differential Growth ◽  
Specific Expression ◽  
Auxin Homeostasis ◽  
Auxin Distribution ◽  
Gene Expression Levels

Asymmetric auxin distribution is instrumental for the differential growth that causes organ bending on tropic stimuli and curvatures during plant development. Local differences in auxin concentrations are achieved mainly by polarized cellular distribution of PIN auxin transporters, but whether other mechanisms involving auxin homeostasis are also relevant for the formation of auxin gradients is not clear. Here we show that auxin methylation is required for asymmetric auxin distribution across the hypocotyl, particularly during its response to gravity. We found that loss-of-function mutants inArabidopsis IAA CARBOXYL METHYLTRANSFERASE1(IAMT1) prematurely unfold the apical hook, and that their hypocotyls are impaired in gravitropic reorientation. This defect is linked to an auxin-dependent increase inPINgene expression, leading to an increased polar auxin transport and lack of asymmetric distribution of PIN3 in theiamt1mutant. Gravitropic reorientation in theiamt1mutant could be restored with either endodermis-specific expression ofIAMT1or partial inhibition of polar auxin transport, which also results in normalPINgene expression levels. We propose that IAA methylation is necessary in gravity-sensing cells to restrict polar auxin transport within the range of auxin levels that allow for differential responses.

NeuroD-null mice are deaf due to a severe loss of the inner ear sensory neurons during development

Development ◽  
2001 ◽  
Vol 128 (3) ◽  
pp. 417-426 ◽  
Author(s):  
W.Y. Kim ◽  
B. Fritzsch ◽  
A. Serls ◽  
L.A. Bakel ◽  
E.J. Huang ◽  
...  
Keyword(s):  
Inner Ear ◽  
Sensory Neurons ◽  
Auditory Evoked Potentials ◽  
Neurotrophin Receptors ◽  
Basic Helix Loop Helix ◽  
Helix Loop Helix ◽  
Developmental Neuroscience ◽  
Profound Deafness ◽  
Key Factor ◽  
Genetic Mechanisms

A key factor in the genetically programmed development of the nervous system is the death of massive numbers of neurons. Therefore, genetic mechanisms governing cell survival are of fundamental importance to developmental neuroscience. We report that inner ear sensory neurons are dependent on a basic helix-loop-helix transcription factor called NeuroD for survival during differentiation. Mice lacking NeuroD protein exhibit no auditory evoked potentials, reflecting a profound deafness. DiI fiber staining, immunostaining and cell death assays reveal that the deafness is due to the failure of inner ear sensory neuron survival during development. The affected inner ear sensory neurons fail to express neurotrophin receptors, TrkB and TrkC, suggesting that the ability of NeuroD to support neuronal survival may be directly mediated through regulation of responsiveness to the neurotrophins.

scholarly journals Developmental and Evolutionary Allometry of the Mammalian Limb Skeleton

2019 ◽  
Vol 59 (5) ◽  
pp. 1356-1368 ◽  
Author(s):  
Kimberly L Cooper
Keyword(s):  
Biological Organization ◽  
Differential Growth ◽  
Cartilage Growth ◽  
Putative Gene ◽  
Evolutionary Allometry ◽  
Order Of Magnitude ◽  
Genetic Mechanisms ◽  
Leg Bones ◽  
Development And Evolution ◽  
Cartilage Growth Plate

Abstract The variety of limb skeletal proportions enables a remarkable diversity of behaviors that include powered flight in bats and flipper-propelled swimming in whales using extremes of a range of homologous limb architectures. Even within human limbs, bone lengths span more than an order of magnitude from the short finger and toe bones to the long arm and leg bones. Yet all of this diversity arises from embryonic skeletal elements that are each a very similar size at formation. In this review article, I survey what is and is not yet known of the development and evolution of skeletal proportion at multiple hierarchical levels of biological organization. These include the cellular parameters of skeletal elongation in the cartilage growth plate, genes associated with differential growth, and putative gene regulatory mechanisms that would allow both covariant and independent evolution of the forelimbs and hindlimbs and of individual limb segments. Although the genetic mechanisms that shape skeletal proportion are still largely unknown, and most of what is known is limited to mammals, it is becoming increasingly apparent that the diversity of bone lengths is an emergent property of a complex system that controls elongation of individual skeletal elements using a genetic toolkit shared by all.

scholarly journals Antagonistic and auxin-dependent phosphoregulation of columella PIN proteins controls lateral root gravitropic setpoint angle in Arabidopsis

2019 ◽  
Author(s):  
Suruchi Roychoudhry ◽  
Katelyn Sageman-Furnas ◽  
Chris Wolverton ◽  
Heather L. Goodman ◽  
Peter Grones ◽  
...  
Keyword(s):  
Molecular Basis ◽  
Lateral Root ◽  
Auxin Transport ◽  
Lateral Roots ◽  
Gravity Vector ◽  
Independent Manner ◽  
Gravitropic Response ◽  
Auxin Distribution ◽  
Columella Cells ◽  
Molecular Framework

AbstractLateral roots of many species are maintained at non-vertical angles with respect to gravity. These gravitropic setpoint angles (GSAs) are intriguing because their maintenance requires that roots are able to effect gravitropic response both with and against the gravity vector. Here we have used the Arabidopsis lateral root in order to investigate the molecular basis of the maintenance of non-vertical GSAs. We show that gravitropism in the lateral root is angle-dependent and that both upward and downward graviresponse requires auxin transport and the generation of auxin asymmetries consistent with the Cholodny-Went model. We show that the symmetry in auxin distribution in lateral roots growing at GSA can be traced back to a net, balanced polarization of PIN3 and PIN7 auxin transporters in the columella cells. Further, upward and downward graviresponse in lateral roots correlates with corresponding changes in PIN3 and PIN7 polar localisation. Finally, we show that auxin, in addition to driving tropic growth in the lateral root, acts within the columella to regulate GSA via the PIN phosphatase subunit RCN1 in a PIN3-dependent and PIN7-independent manner. Together, these findings provide a molecular framework for understanding gravity-dependent nonvertical growth in Arabidopsis lateral roots.

Anatomical changes induced by fire-damaged cambium in two native tree species of the Chaco Region, Argentina

IAWA Journal ◽  
2010 ◽  
Vol 31 (3) ◽  
pp. 283-292 ◽  
Author(s):  
Sandra Bravo
Keyword(s):  
Cross Sections ◽  
Wood Quality ◽  
Cambial Activity ◽  
Wood Formation ◽  
Vessel Diameter ◽  
Fire Damage ◽  
Fire Scars ◽  
Fire Scar ◽  
Chaco Region ◽  
Altered Zone

This study examined anatomical responses to fire damage of the cambium in Schinopsis lorentzii and Aspidosperma quebracho-blanco. Bole cross sections were extracted from specimens with external signs of fire damage. Samples were taken from zones designated normal, discoloured and wound altered. The vessel, fibre, axial and ray parenchyma percentages, tangential vessel diameter, vessels per mm2, rays per mm, and ray width and height of these zones were compared. Fire scars and fire marks were identified on cross sections of S. lorentzii and A. quebracho-blanco. The fire marks reflect minor wounds that did not affect wood formation. The fire scars, on the other hand, are the result of wounds that interrupted cambial activity thus affecting the shape of the bole and causing discolouration of pre-existing wood adjacent to wounds. The wood formed after fire damage included callus, barrier zones at fire scar edges and the formation of ribs of wound wood. The wound altered zone was characterised by a decrease in the percentage of vessels and fibres, an increase in the percentage of axial parenchyma, the formation of grouped rays, a decrease in vessel tangential diameter, and occurrence of fibres with atypical structure. Disorientation in the axial xylem system was observed in the barrier zone. The anatomical responses to cambium damage and formation of discoloured wood and woundwood ribs suggest that wood quality and utilisable volume of bole in the studied species is affected by fire.

Sinuous stem growth in a Douglas-fir (Pseudotsuga menziesii) plantation: growth patterns and wood-quality effects

2000 ◽  
Vol 30 (5) ◽  
pp. 761-768 ◽  
Author(s):  
R Spicer ◽  
B L Gartner ◽  
R L Darbyshire
Keyword(s):  
Pseudotsuga Menziesii ◽  
Compression Wood ◽  
Wood Quality ◽  
Radial Distance ◽  
Wood Properties ◽  
Wood Formation ◽  
Douglas Fir ◽  
Growth Patterns ◽  
Internode Length ◽  
Tree Biomechanics

Stem sinuosity is thought to negatively impact wood quality, but no studies have characterized its vertical and radial effects on wood properties. Here we study wood quality along the entire stem in 25-year-old plantation-grown Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) trees (32 trees total) that had been scored for sinuosity at age 12. We also study compression wood formation in the radial direction for one internode that had been scored for sinuosity at age 12 and subsequently produced 13 more annual rings. Trees with highly sinuous leaders at age 12 were more likely to be sinuous in other years, and developed more slope of grain defect (approximately 15% log volume) than less sinuous trees, but did not differ in the size of the pith-containing core. Leaders originally scored as highly sinuous developed more compression wood than control trees but only near the pith. Internode length did not differ among sinuosity classes. The size of the pith deviations (radial distance from centreline) remained constant up the stem despite a decline in internode length. However, the frequency of pith deviations was highest at 10-15 years, when internode length reached a peak. The relationship between temporal patterns of growth rate, sinuosity, and tree biomechanics deserves further attention.

scholarly journals A Comparative Analysis of Transcription Networks Active in Juvenile and Mature Wood in Populus

2020 ◽  
Author(s):  
Laifu Luo ◽  
Yingying Zhu ◽  
Jinshan Gui ◽  
Tongmin Yin ◽  
Wenchun Luo ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Cell Expansion ◽  
Gene Networks ◽  
Wood Properties ◽  
Wood Formation ◽  
Mature Wood ◽  
Molecular Networks ◽  
Auxin Distribution ◽  
Genome Bisulfite Sequencing ◽  
Chemical Characters

Abstract Background: Juvenile wood (JW) and mature wood (MW) have distinct physical and chemical characters, reflecting the different wood formation over the tree life-span. However, the regulatory mechanisms that distinguish or modulate the characteristics of JW and MW in relation to each other have not been mapped. Using RNA sequencing (RNA-seq) and whole genome bisulfite sequencing (WGBS), we analyzed wood properties associated with JW and MW forming tissue from Populus trees with an identical genetic background.Results: JW and MW of Populus displayed different wood properties as the result of significant differences in transcriptional programs and patterns of DNA methylation. Differences were concentrated in gene networks involved in regulating hormonal signaling pathways responsible for auxin distribution and brassinosteroids biosynthesis as well as genes active in regulating cell expansion and secondary cell wall biosynthesis. An observed correlation between gene expression profiling and DNA methylation indicated that DNA methylation affected expression of the genes related to auxin distribution and brassinosteroids signal transduction, cell expansion in JW and MW formation. Conclusions: Auxin distribution, brassinosteroids biosynthesis and signaling play critical roles in formation of JW and MW. DNA methylation is involved in formatting the transcriptional programs in different development phases which contribute to JW and MW formation. The study sheds light to better understand the molecular networks underlying regulation of wood properties which could inform improvement of wood formation.

scholarly journals Genome-Wide Identification of Long Non-Coding RNAs and Their Potential Functions in Poplar Growth and Phenylalanine Biosynthesis

2021 ◽  
Vol 12 ◽  
Author(s):  
Lei Zhang ◽  
Xiaolan Ge ◽  
Jiujun Du ◽  
Xingqi Cheng ◽  
Xiaopeng Peng ◽  
...  
Keyword(s):  
Target Genes ◽  
Expression Patterns ◽  
Wood Quality ◽  
Target Prediction ◽  
Wood Formation ◽  
Sequencing Analysis ◽  
Oxidoreductase Activity ◽  
Regulatory Processes ◽  
Genome Wide ◽  
Phenylpropanoid Biosynthesis

Poplar is an important bioenergy tree species. lncRNAs play important roles in various biological regulatory processes, and their expression pattern is more tissue-specific than mRNAs. In this study, P. deltoides “Danhong” (Pd) and P. simonii “Tongliao1” (Ps) with different growth rates and wood quality were used as experimental materials, and the transcriptomes of their shoot apical meristem, xylem, and phloem were sequenced. Furthermore, high-throughput RNA sequencing analysis revealed that the expression patterns of genes and lncRNAs are different between the two genotypes. 6,355 lncRNAs were identified. Based on target prediction, lncRNAs and target genes were involved in ADP binding, oxidoreductase activity, phenylpropanoid biosynthesis, and cyanoamino acid metabolism. The DElncRNAs in two poplars were co-expressed with transcription factors and structural genes of lignin and flavonoid pathways. In addition, we found the potential target lncRNAs of miRNA. This result provides basic evidence for a better understanding of the regulatory role of lncRNAs in regulating phenylalanine molecular pathways and wood formation.

scholarly journals Prospects of Genetics and Breeding for Low Phosphate Tolerance: an Integrated Approach from Soil to Cell

2021 ◽  
Author(s):  
Jonathan Odilón Ojeda-Rivera ◽  
Gerardo Alejo-Jacuinde ◽  
Héctor-Rogelio Nájera-González ◽  
Damar López-Arredondo
Keyword(s):  
Food Security ◽  
Production Systems ◽  
Integrated Approach ◽  
Adaptive Responses ◽  
Global Food Security ◽  
Effective Strategies ◽  
Key Factor ◽  
Genetic Mechanisms ◽  
Use Efficiency ◽  
Global Food

Abstract Due to the importance of Phosphorus (P) on plant development and reproduction, global P security has emerged as a key factor towards global food security. Together with multiple agrochemicals, P-based fertilizers have become the pillars that sustain our food production systems. Therefore, improving the genetics and biology of key crops such as maize, rice, wheat and soybean to develop varieties better adapted to thrive under environments that present low phosphate (Pi) availability and that possess higher Pi-fertilizer use efficiency is imperative. In this review, we summarize the current understanding of Pi nutrition in plants, with particular focus on crops, and provide new perspectives on how to harness the ample repertoire of genetic mechanisms behind plant low-Pi adaptive responses that can be utilized to design smart low-Pi tolerant plants. We discuss on the potential of implementing more integrative, versatile and effective strategies by incorporating genome editing and synthetic biology approaches to reduce Pi-fertilizer input and enable global food security in a more sustainable way.

scholarly journals Parkinson’s Disease Associated with GBA Gene Mutations: Molecular Aspects and Potential Treatment Approaches

Acta Naturae ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 70-78
Author(s):  
Konstantin A. Senkevich ◽  
Alena E. Kopytova ◽  
Tatiana S. Usenko ◽  
Anton K. Emelyanov ◽  
Sofya N. Pchelina
Keyword(s):  
Association Studies ◽  
Gene Mutations ◽  
Genome Wide Association Studies ◽  
Gene Encoding ◽  
Parkinsons Disease ◽  
Genome Wide ◽  
Genetic Mechanisms ◽  
Gba Gene ◽  
Intensive Investigation ◽  
Molecular Aspects

Parkinsons disease (PD) is a multifactorial neurodegenerative disease. To date, genome-wide association studies have identified more than 70 loci associated with the risk of PD. Variants in the GBA gene encoding glucocerebrosidase are quite often found in PD patients in all populations across the world, which justifies intensive investigation of this gene. A number of biochemical features have been identified in patients with GBA-associated Parkinsons disease (GBA-PD). In particular, these include decreased activity of glucocerebrosidase and accumulation of the glucosylceramide substrate. These features were the basis for putting forward a hypothesis about treatment of GBA-PD using new strategies aimed at restoring glucocerebrosidase activity and reducing the substrate concentration. This paper discusses the molecular and genetic mechanisms of GBA-PD pathogenesis and potential approaches to the treatment of this form of the disease.

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