Identification of genes and metabolic pathways involved in wounding-induced kiwifruit ripening

Fruit is constantly challenged by wounding events, inducing accelerated ripening and irreversible metabolic changes. However, cognate mechanisms that regulate this process are little known. To expand our knowledge of ripening metabolism induced by wounding, an artificial-wound global transcriptome investigation combined with metabolite profiling study was conducted in postharvest kiwifruit (Actinidia chinensis var. deliciosa (A. Chev.) A. Chev. ‘Hayward’). Wounding treatment promoted fruit ripening, as demonstrated by changes in fruit firmness, ethylene production and respiration activity determined periodically during a ripening period of 8 d at room temperature. Calcium imaging using fluorescent probe Fluo-3 AM revealed spatial dynamics of Ca2+ signaling in the wounding area following 8d ripening. Several sugars including fructose, glucose, and sucrose as well as organic acids such as citric, succinic and galacturonic acid were increased by wounding. Changes of various amino acids in wounded-treated fruit, especially 5-oxoproline and valine along with alternations of soluble alcohols, like myo-inositol were detected. Gene expression analysis of the wounded fruit showed increased expression of genes that are mainly involved in defense response (e.g., AdTLP.1-3, AdPP2C.1-2, AdMALD1), calcium ion binding (e.g., AdCbEFh, AdCLR, AdANX), TCA cycle (e.g., AdMDH.1, AdMDH.2, AdCS), sugars (e.g., AdSUSA.1, AdSPS4, AdABFr), secondary metabolism (e.g., AdPAL.1-3, AdCCR, AdHCT.1-2), lipid processing (e.g., AdGELP.1-4, AdGELP) and pectin degradation (e.g., AdPE.1-2, AdPAE.1-2, AdPG.1-2) as well as in ethylene (AdERF7, AdERF1B, AdACO.1-4) and auxin (AdICE, AdAEFc, AdASII) synthesis and perception. Moreover, genes related to aquaporins, such as AdAQP2, AdAQP4 and AdAQP7 were down-regulated in fruit exposed to wounding. These results demonstrate multiple metabolic points of wounding regulatory control during kiwifruit ripening and provide insights into the molecular basis of wounding-mediated ripening. © 2022 Elsevier Masson SA

Characterisation of protected denomination of origin cheeses: relationships between sensory texture and instrumental data

International audienc

Characterisation of protected denomination of origin cheeses:relationships between sensory texture and instrumental data

International audienc

Paving the Way towards 800 Gbps Quantum-Secured Optical Channel Deployment in Mission-Critical Environments

This article describes experimental research studies conducted towards understanding the implementation aspects of high-capacity quantum-secured optical channels in mission-critical metro-scale operational environments based on Quantum Key Distribution (QKD) technology. The test bed for this research study was carefully designed to mimic such environments. To the best of our knowledge, this is the first time that an 800 Gbps quantum-secured optical channel--along with several other Dense Wavelength Division Multiplexed (DWDM) channels on the C-band and multiplexed with the QKD channel on the O-band--was established at distances up to 100 km, with secure-key rates relevant for practical industry use cases. In addition, during the course of these trials, transporting a blockchain application over this established channel was utilized as a demonstration of securing a financial transaction in transit over a quantum-secured optical channel. In a real-world operational environment, deployment of such high-capacity quantum-secured optical channels multiplexed with the quantum channel will inevitably introduce challenges due to their strict requirements, such as high launch powers and polarization fluctuations. Therefore, in the course of this research, experimental studies were conducted on the impact on the system performance--and specifically on the quantum channel--of several degradation factors present in real-world operational environments, including inter-channel interference (due to Raman scattering and nonlinear effects), attenuation, polarization fluctuations and distance dependency. The findings of this research pave the way towards the deployment of QKD-secured optical channels in high-capacity, metro-scale, mission-critical operational environments, such as Inter-Data Center Interconnects.Comment: 11 pages, 9 figures, 2 table