Translation elongation factor-1α is pivotal for plant heat tolerance despite its pronounced heat-induced aggregation.

The translation elongation factor 1α (EF1α) protein is a highly conserved G protein that is crucial for protein translation in all eukaryotic organisms. EF1α quickly became insoluble at temperatures 42 °C treatment for 2h in vitro, but generally remained soluble in vivo even after being exposed to temperatures as high as 45 °C for an extended period, which suggests that protective mechanisms exist for keeping EF1α soluble in plant cells under heat stress. EF1α had fast in vivo insolubilization when exposed to 45 °C, resulting in about 40% of the protein aggregating after 9 h. Given its established role in protein translation, heat-induced aggregation is most likely to impact the function of the elongation factor. Overexpression of constitutive mutants in both GTP-bound and GDP-bound forms of EF1α resulted in significantly decreased heat tolerance. These findings provide evidence to support the critical role of EF1α, a thermosensitive protein, in the heat tolerance of plants.

Assisted quantum simulation of open quantum systems.

Universal quantum algorithms (UQA) implemented on fault-tolerant quantum computers are expected to achieve an exponential speedup over classical counterparts. However, the deep quantum circuits make the UQA implausible in the current era. With only the noisy intermediate-scale quantum (NISQ) devices in hand, we introduce the quantum-assisted quantum algorithm, which reduces the circuit depth of UQA via NISQ technology. Based on this framework, we present two quantum-assisted quantum algorithms for simulating open quantum systems, which utilize two parameterized quantum circuits to achieve a short-time evolution. We propose a variational quantum state preparation method, as a subroutine to prepare the ancillary state, for loading a classical vector into a quantum state with a shallow quantum circuit and logarithmic number of qubits. We demonstrate numerically our approaches for a two-level system with an amplitude damping channel and an open version of the dissipative transverse field Ising model on two sites.

Electroacupuncture alleviates multifidus muscle injury by modulating mitochondrial function and Ca2+ uptake.

Multifidus muscles maintain the stability of the lumbar spine and play a crucial role in the pathogenesis of nonspecific lower back pain. Previous studies have shown that electroacupuncture (EA) can relieve the symptoms of low back pain and reduce injury to the lumbar multifidus muscles. In this study, a rat model of lumbar multifidus muscle injury was established by 0.05% bupivacaine injection and subsequently treated with EA at bilateral "Weizhong" (BL40) acupoints. Disruption of the function and structure of multifidus muscles, increased cytosolic Ca2+ in multifidus myocytes, and reduced mitochondrial fission and ATP production were observed in the model group. Additionally, increased expression of the mitochondrial calcium uniporter (MCU) promoted mitochondrial reuptake of Ca2+ , reversing the excessive increase in cytoplasmic Ca2+ . However, the excessive increase in MCU not only aggravated the increased cytoplasmic Ca2+ but also decreased the expression of the mitochondrial division proteins dynamin-related protein 1 (Drp1) and mitochondrial fission factor (MFF). EA inhibited the overexpression of MCU, promoted mitochondrial reuptake of Ca2+ , and reversed cytosolic Ca2+ overload. Furthermore, EA regulated the expression of the mitochondrial fission proteins Drp1 and MFF and promoted the production of ATP, helping the recovery of mitochondrial function after multifidus injury. Therefore, EA can protect against bupivacaine-induced mitochondrial dysfunction, possibly by attenuating MCU overexpression in the inner mitochondrial membrane and reducing Ca2+ overloading in muscle cells, thereby protecting mitochondrial function and maintaining the normal energy demand of muscle cells.

The Cellular and Subcellular Organization of the Glucosinolate-Myrosinase System against Herbivores and Pathogens.

Glucosinolates are an important class of secondary metabolites in Brassicales plants with a critical role in chemical defense. Glucosinolates are chemically inactive but can be hydrolyzed by myrosinases to produce a range of chemically active compounds toxic to herbivores and pathogens, thereby constituting the glucosinolate-myrosinase defense system or the mustard oil bomb. During the evolution, Brassicales plants have developed not only complex biosynthetic pathways for production of a large number of glucosinolate structures but also different classes of myrosinases that differ in catalytic mechanisms and substrate specificity. Studies over the past several decades have made important progress in the understanding of the cellular and subcellular organization of the glucosinolate-myrosinase system for rapid and timely detonation of the mustard oil bomb upon tissue damage after herbivore feeding and pathogen infection. Progress has also been made in understanding the mechanisms that herbivores and pathogens have evolved to counter the mustard oil bomb. In this review, we summarize our current understanding of the function and organization of the glucosinolate-myrosinase system in Brassicales plants and discuss both the progresses and future challenges in addressing this complex defense system as an excellent model for analyzing plant chemical defense.

A tissue atlas of cadmium accumulation and the correlation with thiol-containing chelates in zucchini provide insights into cadmium partitioning and food safety.

Widespread heavy metal pollution in soils has posed serious threat to vegetable production and food security, yet little is still known about heavy metal accumulation and distribution in the majority of vegetable crops. Here, we report the generation of a tissue atlas of cadmium accumulation in zucchini (Cucurbita pepo var. Giromontial), a globally important cucurbit crop, based on two-season experiment with six genotypes grown under cadmium contaminated soils. Plant growth and development as manifested by biomass, flowering time and plant architecture were unaffected by 10 mg/kg cadmium treatment, but high level of cadmium enrichment was detected in all genotypes. Roots accumulated the largest amount of cadmium, whereas the cadmium concentrations in fruits was also considerable. The exocarps of fruits possessed nearly half of the total cadmium in fruits, rendering it a "hotspot" of safety risk. Measurement of the thiol-containing chelates revealed that concentration of GSH but not PCs was correlated with the cadmium concentration in subdivided fruit tissues, suggesting a mechanism of phloem-specific transportation of cadmium in the form of Cd-GSH. Based on the collective data, a tentative model describing the relationship between long-distance phloem transport and cadmium distribution in sink organs is proposed. The implications for food safety are discussed.