The Experts below are selected from a list of 87 Experts worldwide ranked by ideXlab platform
Rujin Chen - One of the best experts on this subject based on the ideXlab platform.
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Functional Genomics and Genetic Control of Compound Leaf Development in Medicago truncatula : An Overview
Methods in molecular biology (Clifton N.J.), 2018Co-Authors: Rujin ChenAbstract:Diverse forms of leaves are present in nature. However, the regulatory mechanisms that underpin the development of diverse leaf forms remain enigmatic. The initiation of leaf primordia from the periphery of shoot apical meristem (SAM) requires downregulation of the class 1 knotted-like homeobox KNOXI proteins. In plants with simple leaves, this downregulation is permanent, consistent with leaves being determinant organs. In most of plants with Compound leaves, the KNOXI proteins are reactivated in developing leaf primordia, and this reactivation is required for the development of Compound leaves in these plants. Surprisingly, in Medicago truncatula and pea (Pisum sativum) that belong to the so-called inverted repeat-lacking clade (IRLC) of legume plants, the KNOXI proteins are not reactivated in leaf primordia and therefore not likely involved in the development of Compound leaves in these plants. Instead, the legume FLORICAULA/LEAFY orthologues, UNIFOLIATA (UNI) and SINGLE LEAFLET1 (SGL1), are required for the initiation and development of lateral leaflet primordia in pea and M. truncatula plants, respectively. On the other hand, PALMATE-LIKE PENTAFOLIATA1 (PALM1) encoding a novel Cys(2)His(2) zinc finger transcription factor is required to suppress a morphogenetic activity at the leaf margin by negatively regulating SGL1 gene expression, and Fused Compound LEAF1 (FCL1) encoding a class M KNOX protein is required for the development of the leaf proximo-distal axis and organ boundary separation in M. truncatula. Thus, these recent studies have shown that SGL1/UNI, FCL1, and PALM1 provide a genetic framework for our understanding of Compound leaf development in the legume plants.
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Regulation of Compound Leaf Development in Medicago truncatula by Fused Compound Leaf1, a Class M KNOX Gene
The Plant cell, 2011Co-Authors: Jianling Peng, Hongliang Wang, Yingqing Guo, Guihua Bai, Rujin ChenAbstract:Medicago truncatula is a legume species belonging to the inverted repeat lacking clade (IRLC) with trifoliolate Compound leaves. However, the regulatory mechanisms underlying development of trifoliolate leaves in legumes remain largely unknown. Here, we report isolation and characterization of Fused Compound leaf1 (fcl1) mutants of M. truncatula. Phenotypic analysis suggests that FCL1 plays a positive role in boundary separation and proximal-distal axis development of Compound leaves. Map-based cloning indicates that FCL1 encodes a class M KNOX protein that harbors the MEINOX domain but lacks the homeodomain. Yeast two-hybrid assays show that FCL1 interacts with a subset of Arabidopsis thaliana BEL1-like proteins with slightly different substrate specificities from the Arabidopsis homolog KNATM-B. Double mutant analyses with M. truncatula single leaflet1 (sgl1) and palmate-like pentafoliata1 (palm1) leaf mutants show that fcl1 is epistatic to palm1 and sgl1 is epistatic to fcl1 in terms of leaf complexity and that SGL1 and FCL1 act additively and are required for petiole development. Previous studies have shown that the canonical KNOX proteins are not involved in Compound leaf development in IRLC legumes. The identification of FCL1 supports the role of a truncated KNOX protein in Compound leaf development in M. truncatula.
W. Grant Mcgimpsey - One of the best experts on this subject based on the ideXlab platform.
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Photochemistry of Aryl Vinyl Sulfides and Aryl Vinyl Ethers: Evidence for the Formation of Thiocarbonyl and Carbonyl Ylides
The Journal of organic chemistry, 1996Co-Authors: James P. Dittami, Yalin Luo, David B. Moss, W. Grant McgimpseyAbstract:Aryl vinyl thioethers 5a and 9a and aryl vinyl ethers 5b and 9b form ylide intermediates following laser irradiation at 308 nm. In benzene, the ylides possess long-lived absorption bands in the 600-800 nm region with a second weaker band at approximately 460 nm. In methanol, a known quencher of zwitterionic species, the lifetimes are reduced significantly. The decay kinetics measured within the long wavelength absorption envelope vary with wavelength, indicating the presence of more than one ylide species. Formation of the ylides occurs via a naphthalene-like triplet state in the case of aryl vinyl ethers, while for the thioethers the multiplicity of the ylide precursor could be either singlet or triplet. Product formation in benzene for 5a and 5b involves ring closure of the ylide to produce dihydrothiophene and dihydrofuran products, respectively. For short periods of irradiation (either lamps or laser) a mixture of cis- and trans-Fused products is observed, while for prolonged irradiation only the cis-Fused Compound is detected, suggesting a photoenolization mechanism for conversion of trans to cis. In addition to products derived from ring closure, 9a provides intramolecular addition product 12. Conversely, the ylide derived from 9b gives rise to the [3 + 2] cycloaddition product 13.
James P. Dittami - One of the best experts on this subject based on the ideXlab platform.
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Photochemistry of Aryl Vinyl Sulfides and Aryl Vinyl Ethers: Evidence for the Formation of Thiocarbonyl and Carbonyl Ylides
The Journal of organic chemistry, 1996Co-Authors: James P. Dittami, Yalin Luo, David B. Moss, W. Grant McgimpseyAbstract:Aryl vinyl thioethers 5a and 9a and aryl vinyl ethers 5b and 9b form ylide intermediates following laser irradiation at 308 nm. In benzene, the ylides possess long-lived absorption bands in the 600-800 nm region with a second weaker band at approximately 460 nm. In methanol, a known quencher of zwitterionic species, the lifetimes are reduced significantly. The decay kinetics measured within the long wavelength absorption envelope vary with wavelength, indicating the presence of more than one ylide species. Formation of the ylides occurs via a naphthalene-like triplet state in the case of aryl vinyl ethers, while for the thioethers the multiplicity of the ylide precursor could be either singlet or triplet. Product formation in benzene for 5a and 5b involves ring closure of the ylide to produce dihydrothiophene and dihydrofuran products, respectively. For short periods of irradiation (either lamps or laser) a mixture of cis- and trans-Fused products is observed, while for prolonged irradiation only the cis-Fused Compound is detected, suggesting a photoenolization mechanism for conversion of trans to cis. In addition to products derived from ring closure, 9a provides intramolecular addition product 12. Conversely, the ylide derived from 9b gives rise to the [3 + 2] cycloaddition product 13.
Guozhu Zhang - One of the best experts on this subject based on the ideXlab platform.
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Gold(I)-Catalyzed Tandem Transformation with Diynes: Rapid Access to Linear Cyclopentenone-Fused Polycyclic Molecules.
Angewandte Chemie (International ed. in English), 2015Co-Authors: Bin Chen, Tian Zhou, Qingshan Tian, Guozhu ZhangAbstract:An efficient and convenient synthesis of useful linear cyclopentenone-Fused polycyclic Compounds has been achieved through a novel gold(I)-catalyzed transformation of diynes. The method demonstrates high product yields and tolerates of a wide variety of important functional groups. Gold-vinylidene formation, methoxy group migration, and Nazarov-type cyclization are proposed to be the key steps in the reaction pathway. The synthetic utility of this method is demonstrated by converting the product to eight-membered-ring-Fused Compound.
Jianling Peng - One of the best experts on this subject based on the ideXlab platform.
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Regulation of Compound Leaf Development in Medicago truncatula by Fused Compound Leaf1, a Class M KNOX Gene
The Plant cell, 2011Co-Authors: Jianling Peng, Hongliang Wang, Yingqing Guo, Guihua Bai, Rujin ChenAbstract:Medicago truncatula is a legume species belonging to the inverted repeat lacking clade (IRLC) with trifoliolate Compound leaves. However, the regulatory mechanisms underlying development of trifoliolate leaves in legumes remain largely unknown. Here, we report isolation and characterization of Fused Compound leaf1 (fcl1) mutants of M. truncatula. Phenotypic analysis suggests that FCL1 plays a positive role in boundary separation and proximal-distal axis development of Compound leaves. Map-based cloning indicates that FCL1 encodes a class M KNOX protein that harbors the MEINOX domain but lacks the homeodomain. Yeast two-hybrid assays show that FCL1 interacts with a subset of Arabidopsis thaliana BEL1-like proteins with slightly different substrate specificities from the Arabidopsis homolog KNATM-B. Double mutant analyses with M. truncatula single leaflet1 (sgl1) and palmate-like pentafoliata1 (palm1) leaf mutants show that fcl1 is epistatic to palm1 and sgl1 is epistatic to fcl1 in terms of leaf complexity and that SGL1 and FCL1 act additively and are required for petiole development. Previous studies have shown that the canonical KNOX proteins are not involved in Compound leaf development in IRLC legumes. The identification of FCL1 supports the role of a truncated KNOX protein in Compound leaf development in M. truncatula.
