43 research outputs found
BIOCHEMICAL STUDIES OF MICROELEMENTS IN GREEN PLANTS II. THE CHEMICAL COMPOSITION OF RICE PLANT AND BARLEY AFFECTED BY IRON DEFICIENCY
BIOCHEMICAL STUDIES OF MICROELEMENTS IN GREEN PLANTS V. EFFECTS OF MICROELEMENT DEFICIENCIES ON THE RATES OF PHOTOSYNTHESIS AND RESPIRATION OF RICE AND BARLEY PLANTS
BIOCHEMICAL STUDIES OF MICROELEMENTS IN GREEN PLANTS 1. DEFICIENCY SYMPTOMS OF MICROELEMENTS ON BARLEY PLANTS AND CHANGES OF INDOLACETIC ACID OXIDASE ACTIVITY
BIOCHEMICAL STUDIES OF MICROELEMENTS IN GREEN PLANTS VI. EFFECTS OF MICROELEMENT DEFICIENCIES ON THE STATUS OF PHOSPHORUS FRACTIONS IN BARLEY PLANTS
BIOCHEIMICAL STUDIES OF MICROELEMENTS IN GREEN PLANTS IV. STATUS OF CHLOROPLASTS AND RATE OF PHOTOSYNTHESIS IN MICROELEMENT DEFICIENT BARLEY LEAVES
BIOCHEMICAL STUDIES OF MICROELEMENTS IN GREEN PLANTS III. ON THE COMPOSITION OF NITROGENOUS CONSTITUENTS OF THE ZINC DEFICIENT BARLEY LEAVES AND THE MATERIAL EXUDATED FROM THEM
Cryo-EM structures of human zinc transporter ZnT7 reveal the mechanism of Zn²⁺ uptake into the Golgi apparatus
クライオ電子顕微鏡により、ゴルジ体の亜鉛輸送体による亜鉛輸送機構の全容を解明 細胞の亜鉛恒常性維持機構の理解に大きな進展. 京都大学プレスリリース. 2023-08-29.Zinc ions (Zn²⁺) are vital to most cells, with the intracellular concentrations of Zn²⁺ being tightly regulated by multiple zinc transporters located at the plasma and organelle membranes. We herein present the 2.2-3.1 Å-resolution cryo-EM structures of a Golgi-localized human Zn²⁺/H+ antiporter ZnT7 (hZnT7) in Zn²⁺-bound and unbound forms. Cryo-EM analyses show that hZnT7 exists as a dimer via tight interactions in both the cytosolic and transmembrane (TM) domains of two protomers, each of which contains a single Zn²⁺-binding site in its TM domain. hZnT7 undergoes a TM-helix rearrangement to create a negatively charged cytosolic cavity for Zn²⁺ entry in the inward-facing conformation and widens the luminal cavity for Zn²⁺ release in the outward-facing conformation. An exceptionally long cytosolic histidine-rich loop characteristic of hZnT7 binds two Zn²⁺ ions, seemingly facilitating Zn²⁺ recruitment to the TM metal transport pathway. These structures permit mechanisms of hZnT7-mediated Zn²⁺ uptake into the Golgi to be proposed
A randomized phase II trial of intra-arterial chemotherapy using SM-11355 (Miriplatin) for hepatocellular carcinoma
Gene Expression and Accumulation of Rubisco in Bundle Sheath and Mesophyll Cells during Leaf Development and Senescence in Rice, a C3 Plant
Gene expression of ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) large subunit (rbcL) and small subunit (rbcS) in bundle sheath and mesophyll cells of rice, a C3 plant, was examined during leaf development and senescence by in situ hybridization. Localization of Rubisco protein in both cells was also examined by immuno-electron microscopy. Gene expression and accumulation of Rubisco were related with the chlorophyll fluorescence parameters. The chlorophyll fluorescence parameters, such as Fv/Fm and Φpsii, gradually increased during leaf development with the increase in the accumulation of Rubisco. However, the chlorophyll fluorescence parameters decreased earlier than the Rubisco content during leaf senescence. The expression of rbcS decreased earlier in bundle sheath cells than in mesophyll cells during leaf development, whereas the expression of rbcL in both cells was retained during leaf development and decreased during leaf senescence. On the other hand, Rubisco content of bundle sheath and mesophyll cells increased during leaf development and decreased during leaf senescence. Rubisco was retained even after the disappearance of the expression of rbcS and rbcL detectable by in situ hybridization. The present results suggest that the expression pattern of rbcS in bundle sheath cells was somewhat different from that in mesophyll cells, but this difference was not reflected in Rubisco content