MicroRNAs （miRNAs） are -21-nucleotide noncoding RNAs that play critical roles in regulating plant growth and development through directing the degradation of target mRNAs. Axillary meristem activity, and hence shoot...MicroRNAs （miRNAs） are -21-nucleotide noncoding RNAs that play critical roles in regulating plant growth and development through directing the degradation of target mRNAs. Axillary meristem activity, and hence shoot branching, is influenced by a complicated network that involves phytohormones such as auxin, cytokinin, and strigolactone. GAI, RGA, and SCR （GRAS） family members take part in a variety of developmental processes, including axillary bud growth. Here, we show that the Arabidopsis thaliana microRNA171c （miR171c） acts to negatively regulate shoot branching through targeting GRAS gene family members SCARECROW-LIKE6-Ⅱ （SCL6-Ⅱ）, SCL6-Ⅲ, and SCL6-Ⅳ for cleavage. Transgenic plants overexpressing MIR171c （35Spro-MIR171c） and sd6-Ⅱ scl6-Ⅲ scl6-Ⅳ triple mutant plants exhibit a similar reduced shoot branching phenotype. Expression of any one of the miR171c-resistant versions of SCL6-Ⅱ, SCL6-Ⅲ, and SCL6-Ⅳ in 35Spro- MIR171c plants rescues the reduced shoot branching phenotype. Scl6-Ⅱ scl6-Ⅲ scl6-Ⅳ mutant plants exhibit pleiotropic phenotypes such as increased chlorophyll accumulation, decreased primary root elongation, and abnormal leaf and flower patterning. SCL6-Ⅱ, SCL6-Ⅲ, and SCL6-Ⅳ are located to the nucleus, and show transcriptional activation activity. Our results suggest that miR171c-targeted SCL6-Ⅱ, SCL6-Ⅲ, and SCL6-Ⅳ play an important role in the regulation of shoot branch production.展开更多
In this paper, we consider a bisexual Galton-Watson branching process whose offspring probability distribution is controlled by a random environment proccss. Some results for the probability generating functions assoc...In this paper, we consider a bisexual Galton-Watson branching process whose offspring probability distribution is controlled by a random environment proccss. Some results for the probability generating functions associated with the process are obtained and sufficient conditions for certain extinction and for non-certain extinction are established.展开更多
Polar transport of the phytohormone auxin and the establishment of localized auxin maxima regulate em- bryonic development, stem cell maintenance, root and shoot architecture, and tropic growth responses. The past dec...Polar transport of the phytohormone auxin and the establishment of localized auxin maxima regulate em- bryonic development, stem cell maintenance, root and shoot architecture, and tropic growth responses. The past decade has been marked by dramatic progress in efforts to elucidate the complex mechanisms by which auxin transport regulates plant growth. As the understanding of auxin transport regulation has been increasingly elaborated, it has become clear that this process is involved in almost all plant growth and environmental responses in some way. However, we still lack information about some basic aspects of this fundamental regulatory mechanism. In this review, we present what we know （or what we think we know） and what we do not know about seven auxin-regulated processes. We discuss the role of auxin transport in gravitropism in primary and lateral roots, phototropism, shoot branching, leaf expansion, and venation. We also discuss the auxin reflux/fountain model at the root tip, flavonoid modulation of auxin transport processes, and outstanding aspects of post-translational regulation of auxin transporters. This discussion is not meant to be exhaustive, but highlights areas in which generally held assumptions require more substantive validation.展开更多
With the discovery of strigolactones as root exudate signals that trigger parasitic weed seed germination, and then as a branching inhibitor and plant hormone, the next phase of strigolactone research has quickly reve...With the discovery of strigolactones as root exudate signals that trigger parasitic weed seed germination, and then as a branching inhibitor and plant hormone, the next phase of strigolactone research has quickly revealed this hormone class as a major player in optimizing plant growth and development. From the early stages of plant evolution, it seems that strigolactones were involved in enabling plants to modify growth in order to gain advantage in competi- tion with neighboring organisms for limited resources. For example, a moss plant can alter its growth in response to strigolactones emanating from a neighbor. Within a higher plant, strigolactones appear to be involved in controlling the balance of resource distribution via strategic modification of growth and development. Most notably, higher plants that encounter phosphate deficiency increase strigolactone production, which changes root growth and promotes fungal symbiosis to enhance phosphate intake. The shoot also changes by channeling resources away from unessential leaves and branches and into the main stem and root system. This hormonal response is a key adaption that radically alters whole-plant architecture in order to optimize growth and development under diverse environmental conditions.展开更多
The product of the ∧0/b （-B/0） differential production cross-section and the branching fraction of the decay ∧0/b→ J/ψ pK-（-B/0→ J/ψ-K＊（892）0）is measured as a function of the beauty hadron transverse mome...The product of the ∧0/b （-B/0） differential production cross-section and the branching fraction of the decay ∧0/b→ J/ψ pK-（-B/0→ J/ψ-K＊（892）0）is measured as a function of the beauty hadron transverse momentum, PT, and rapidity, y. The kinematic region of the measurements is pT〈20 GeV/c and 2.0 〈g〈4.5.The measurements use a data sample corresponding to an integrated luminosity of 3fb-1 collected by the LHCb detector in pp collisions at centre-of-mass energies √s=7 TeV in 2011 and √s=8 TeV in 2012. Based on previous LHCb results of the fragmentation fraction ratio,f∧0/b/fd,the branching fraction of the decay ∧0/b→ J/ψ pK-is measured to be B（∧0/b→ J/ψ pK-）=（3.17±0.04±0.07±0.34＋0.45/-0.28）×10-4,where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay -B/0 →J/ψ-K＊（892）0,and the fourth is due to the knowledge of f∧0/b/fd.The sum of the asymmetries in the production and decay between ∧0/b and ∧0/bis also measured as a function of PT and y.The previously published branching fraction of ∧0/b→ J/ψ pπ-,relative to that of ∧0/b→ J/ψ pK-,is updated. The branching fractions of ∧0/b→P＋c（→ J/ψp）K-are determined.展开更多
The concepts of branching chain in random environmnet and canonical branching chain in random environment are introduced. Moreover the existence of these chains is proved. Finally the exact formulas of mathematical ex...The concepts of branching chain in random environmnet and canonical branching chain in random environment are introduced. Moreover the existence of these chains is proved. Finally the exact formulas of mathematical expectation and variance of branching chain in random environment are also given.展开更多
The shapes of trees are complex and fractal-like, and they have a set of physical, mechanical and biological functions. The relation between them always draws attention of human beings throughout history and, focusing...The shapes of trees are complex and fractal-like, and they have a set of physical, mechanical and biological functions. The relation between them always draws attention of human beings throughout history and, focusing on the relation between shape and structural strength, architects have designed a number of treelike structures, referred as dendriforms. The replication and adoption of the treelike patterns for constructing architectural structures have been varied in different time periods based on the existing and advanced knowledge and available technologies. This paper, by briefly discussing the biological functions and the mechanical properties of trees with regard to their shapes, overviews and investigates the chronological evolution and advancements of dendriform and arboreal structures in architec- ture referring to some important historical as well as contemporary examples.展开更多
Shoot branching,determining plant architecture and crop yield,is critically controlled by strigolactones(SLs).However,how SLs inhibit shoot branching after its perception by the receptor complex remains largely obscur...Shoot branching,determining plant architecture and crop yield,is critically controlled by strigolactones(SLs).However,how SLs inhibit shoot branching after its perception by the receptor complex remains largely obscure.In this study,using the transcriptomic and genetic analyss as well as biochemical studies,we reveal the key role of BES1 in the SL-regulated shoot branching.Wedemonstrate that BES1 and D53-like SMXLs,the substrates of SL receptor complex D14–MAX2,interact with each other to inhibit BRC1 expression,which specifically triggers the SL-regulated transcriptional network in shoot branching.BES1 directly binds the BRC1 promoter and recruits SMXLs to inhibit BRC1 expression.Interestingly,despite being the shared component by SL and brassinosteroid(BR)signaling,BES1 gains signal specificity through different mechanisms in response to BR and SL signals.展开更多
We consider a branching random walk in random environments, where the particles are reproduced as a branching process with a random environment (in time), and move independently as a random walk on ? with a random env...We consider a branching random walk in random environments, where the particles are reproduced as a branching process with a random environment (in time), and move independently as a random walk on ? with a random environment (in locations). We obtain the asymptotic properties on the position of the rightmost particle at time n, revealing a phase transition phenomenon of the system.展开更多
Because plants are sessile organisms,the ability to adapt to a wide range of environmental conditions is critical for their survival.As a consequence,plants use hormones to regulate growth,mitigate biotic and abiotic ...Because plants are sessile organisms,the ability to adapt to a wide range of environmental conditions is critical for their survival.As a consequence,plants use hormones to regulate growth,mitigate biotic and abiotic stresses,and to communicate with other organisms.Many plant hormones function plei-otropically in vivo,and often work in tandem with other hormones that are chemically distinct.A newly-defined class of plant hormones,the strigolactones,cooperate with auxins and cytokinins to control shoot branching and the outgrowth of lateral buds.Strigolactones were originally identified as compounds that stimulated the germination of parasitic plant seeds,and were also demonstrated to induce hyphal branching in arbuscular mycorrhizal(AM) fungi.AM fungi form symbioses with higher plant roots and mainly facilitate the absorption of phosphate from the soil.Conforming to the classical definition of a plant hormone,strigolactones are produced in the roots and translocated to the shoots where they inhibit shoot outgrowth and branching.The biosynthesis of this class of compounds is regulated by soil nutrient availability,i.e.the plant will increase its production of strigolactones when the soil phosphate concentration is limited,and decrease production when phosphates are in ample supply.Strigolactones that affect plant shoot branching,AM fungal hyphal branching,and seed germination in parasitic plants facilitate chemical synthesis of similar compounds to control these and other biological processes by exogenous application.展开更多
文摘MicroRNAs （miRNAs） are -21-nucleotide noncoding RNAs that play critical roles in regulating plant growth and development through directing the degradation of target mRNAs. Axillary meristem activity, and hence shoot branching, is influenced by a complicated network that involves phytohormones such as auxin, cytokinin, and strigolactone. GAI, RGA, and SCR （GRAS） family members take part in a variety of developmental processes, including axillary bud growth. Here, we show that the Arabidopsis thaliana microRNA171c （miR171c） acts to negatively regulate shoot branching through targeting GRAS gene family members SCARECROW-LIKE6-Ⅱ （SCL6-Ⅱ）, SCL6-Ⅲ, and SCL6-Ⅳ for cleavage. Transgenic plants overexpressing MIR171c （35Spro-MIR171c） and sd6-Ⅱ scl6-Ⅲ scl6-Ⅳ triple mutant plants exhibit a similar reduced shoot branching phenotype. Expression of any one of the miR171c-resistant versions of SCL6-Ⅱ, SCL6-Ⅲ, and SCL6-Ⅳ in 35Spro- MIR171c plants rescues the reduced shoot branching phenotype. Scl6-Ⅱ scl6-Ⅲ scl6-Ⅳ mutant plants exhibit pleiotropic phenotypes such as increased chlorophyll accumulation, decreased primary root elongation, and abnormal leaf and flower patterning. SCL6-Ⅱ, SCL6-Ⅲ, and SCL6-Ⅳ are located to the nucleus, and show transcriptional activation activity. Our results suggest that miR171c-targeted SCL6-Ⅱ, SCL6-Ⅲ, and SCL6-Ⅳ play an important role in the regulation of shoot branch production.
文摘In this paper, we consider a bisexual Galton-Watson branching process whose offspring probability distribution is controlled by a random environment proccss. Some results for the probability generating functions associated with the process are obtained and sufficient conditions for certain extinction and for non-certain extinction are established.
基金This work was funded by the National Science Foundation，A.S.M.and Purdue Agriculture Research Foundation grant to W.A.P
文摘Polar transport of the phytohormone auxin and the establishment of localized auxin maxima regulate em- bryonic development, stem cell maintenance, root and shoot architecture, and tropic growth responses. The past decade has been marked by dramatic progress in efforts to elucidate the complex mechanisms by which auxin transport regulates plant growth. As the understanding of auxin transport regulation has been increasingly elaborated, it has become clear that this process is involved in almost all plant growth and environmental responses in some way. However, we still lack information about some basic aspects of this fundamental regulatory mechanism. In this review, we present what we know （or what we think we know） and what we do not know about seven auxin-regulated processes. We discuss the role of auxin transport in gravitropism in primary and lateral roots, phototropism, shoot branching, leaf expansion, and venation. We also discuss the auxin reflux/fountain model at the root tip, flavonoid modulation of auxin transport processes, and outstanding aspects of post-translational regulation of auxin transporters. This discussion is not meant to be exhaustive, but highlights areas in which generally held assumptions require more substantive validation.
文摘With the discovery of strigolactones as root exudate signals that trigger parasitic weed seed germination, and then as a branching inhibitor and plant hormone, the next phase of strigolactone research has quickly revealed this hormone class as a major player in optimizing plant growth and development. From the early stages of plant evolution, it seems that strigolactones were involved in enabling plants to modify growth in order to gain advantage in competi- tion with neighboring organisms for limited resources. For example, a moss plant can alter its growth in response to strigolactones emanating from a neighbor. Within a higher plant, strigolactones appear to be involved in controlling the balance of resource distribution via strategic modification of growth and development. Most notably, higher plants that encounter phosphate deficiency increase strigolactone production, which changes root growth and promotes fungal symbiosis to enhance phosphate intake. The shoot also changes by channeling resources away from unessential leaves and branches and into the main stem and root system. This hormonal response is a key adaption that radically alters whole-plant architecture in order to optimize growth and development under diverse environmental conditions.
基金Supported by CERN and national agencies:CAPES,CNPq,FAPERJ and FINEP(Brazil)NSFC(China)+17 种基金CNRS/IN2P3(France)BMBF,DFG,HGF and MPG(Germany)INFN(Italy)FOM and NWO(The Netherlands)MNi SW and NCN(Poland)MEN/IFA(Romania)Min ES and FANO(Russia)Min ECo(Spain)SNSF and SER(Switzerland)NASU(Ukraine)STFC(United Kingdom)NSF(USA)supported by IN2P3(France),KIT and BMBF(Germany),INFN(Italy),NWOSURF(The Netherlands),PIC(Spain),Grid PP(United Kingdom)support from EPLANET,Marie Sk lodowska-Curie ActionsERC(European Union),Conseil général de Haute-Savoie,Labex ENIGMASS and OCEVU,RégionAuvergne(France),RFBR(Russia),Xunta GalGENCAT(Spain),Royal Society and Royal Commission for the Exhibition of 1851(United Kingdom)
文摘The product of the ∧0/b （-B/0） differential production cross-section and the branching fraction of the decay ∧0/b→ J/ψ pK-（-B/0→ J/ψ-K＊（892）0）is measured as a function of the beauty hadron transverse momentum, PT, and rapidity, y. The kinematic region of the measurements is pT〈20 GeV/c and 2.0 〈g〈4.5.The measurements use a data sample corresponding to an integrated luminosity of 3fb-1 collected by the LHCb detector in pp collisions at centre-of-mass energies √s=7 TeV in 2011 and √s=8 TeV in 2012. Based on previous LHCb results of the fragmentation fraction ratio,f∧0/b/fd,the branching fraction of the decay ∧0/b→ J/ψ pK-is measured to be B（∧0/b→ J/ψ pK-）=（3.17±0.04±0.07±0.34＋0.45/-0.28）×10-4,where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay -B/0 →J/ψ-K＊（892）0,and the fourth is due to the knowledge of f∧0/b/fd.The sum of the asymmetries in the production and decay between ∧0/b and ∧0/bis also measured as a function of PT and y.The previously published branching fraction of ∧0/b→ J/ψ pπ-,relative to that of ∧0/b→ J/ψ pK-,is updated. The branching fractions of ∧0/b→P＋c（→ J/ψp）K-are determined.
文摘The concepts of branching chain in random environmnet and canonical branching chain in random environment are introduced. Moreover the existence of these chains is proved. Finally the exact formulas of mathematical expectation and variance of branching chain in random environment are also given.
文摘The shapes of trees are complex and fractal-like, and they have a set of physical, mechanical and biological functions. The relation between them always draws attention of human beings throughout history and, focusing on the relation between shape and structural strength, architects have designed a number of treelike structures, referred as dendriforms. The replication and adoption of the treelike patterns for constructing architectural structures have been varied in different time periods based on the existing and advanced knowledge and available technologies. This paper, by briefly discussing the biological functions and the mechanical properties of trees with regard to their shapes, overviews and investigates the chronological evolution and advancements of dendriform and arboreal structures in architec- ture referring to some important historical as well as contemporary examples.
基金Supported by NSFC 31430046(to X.W),31661143024(to X.W.)National Key Research and Development Plan 2016YFD0100403(to S.S.)+1 种基金the Ministry of Agriculture Innovation team plan(0120150092 to X.W.)the School Independent Scientific and Technological Innovation Foundation and Research Startup Foundation of Huazhong Agricultural University(2662015PY020 and 2014RC002 to X.W.).
文摘Shoot branching,determining plant architecture and crop yield,is critically controlled by strigolactones(SLs).However,how SLs inhibit shoot branching after its perception by the receptor complex remains largely obscure.In this study,using the transcriptomic and genetic analyss as well as biochemical studies,we reveal the key role of BES1 in the SL-regulated shoot branching.Wedemonstrate that BES1 and D53-like SMXLs,the substrates of SL receptor complex D14–MAX2,interact with each other to inhibit BRC1 expression,which specifically triggers the SL-regulated transcriptional network in shoot branching.BES1 directly binds the BRC1 promoter and recruits SMXLs to inhibit BRC1 expression.Interestingly,despite being the shared component by SL and brassinosteroid(BR)signaling,BES1 gains signal specificity through different mechanisms in response to BR and SL signals.
基金the National Natural Science Foundation of China (Grant Nos. 10271020,10471012)SRF for ROCS, SEM (Grant No. [2005]564)
文摘We consider a branching random walk in random environments, where the particles are reproduced as a branching process with a random environment (in time), and move independently as a random walk on ? with a random environment (in locations). We obtain the asymptotic properties on the position of the rightmost particle at time n, revealing a phase transition phenomenon of the system.
基金Supported by the National Natural Science Foundation of China (Grant No. 30623011)
文摘Because plants are sessile organisms,the ability to adapt to a wide range of environmental conditions is critical for their survival.As a consequence,plants use hormones to regulate growth,mitigate biotic and abiotic stresses,and to communicate with other organisms.Many plant hormones function plei-otropically in vivo,and often work in tandem with other hormones that are chemically distinct.A newly-defined class of plant hormones,the strigolactones,cooperate with auxins and cytokinins to control shoot branching and the outgrowth of lateral buds.Strigolactones were originally identified as compounds that stimulated the germination of parasitic plant seeds,and were also demonstrated to induce hyphal branching in arbuscular mycorrhizal(AM) fungi.AM fungi form symbioses with higher plant roots and mainly facilitate the absorption of phosphate from the soil.Conforming to the classical definition of a plant hormone,strigolactones are produced in the roots and translocated to the shoots where they inhibit shoot outgrowth and branching.The biosynthesis of this class of compounds is regulated by soil nutrient availability,i.e.the plant will increase its production of strigolactones when the soil phosphate concentration is limited,and decrease production when phosphates are in ample supply.Strigolactones that affect plant shoot branching,AM fungal hyphal branching,and seed germination in parasitic plants facilitate chemical synthesis of similar compounds to control these and other biological processes by exogenous application.
