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This document is a special issue of the journal "Life" titled "Advances in Space Biology." It discusses the importance of space biology in both robotic and human space programs, particularly in relation to the exploration of Venus, Jupiter's icy moons, the Moon, and Mars. The document highlights the challenges posed by the space environment, such as altered gravity, radiation, and isolation, and the need for comprehensive risk models and countermeasures. It also explores the effects of microgravity on the musculo-skeletal system, the parallels between space and age-related health issues, the impact of space on the skin microbiome, and the search for life beyond Earth. The articles in this special issue contribute to our understanding of space biology. [Extracted from the article]

Human Space exploration has created new challenges and new opportunities for science. Reaching beyond the Earth's surface has raised the issue of the importance of gravity for the development and the physiology of biological systems, while giving scientists the tools to study the mechanisms of response and adaptation to the microgravity environment. As life has evolved under the constant influence of gravity, gravity affects biological systems at a very fundamental level. Owing to limited access to spaceflight platforms, scientists rely heavily on on-ground facilities that reproduce, to a different extent, microgravity or its effects. However, the technical constraints of counterbalancing the gravitational force on Earth add complexity to data interpretation. In-flight experiments are also not without their challenges, including additional stressors, such as cosmic radiation and lack of convection. It is thus extremely important in Space biology to design experiments in a way that maximizes the scientific return and takes into consideration all the variables of the chosen setup, both on-ground or on orbit. This review provides a critical analysis of current ground-based and spaceflight facilities. In particular, the focus was given to experimental design to offer the reader the tools to select the appropriate setup and to appropriately interpret the results. [ABSTRACT FROM AUTHOR]

Plants evolved several strategies to cope with the ever-changing environment. One example of this is given by seed germination, which must occur when environmental conditions are suitable for plant life. In the model system Arabidopsis thaliana seed germination is induced by light; however in nature, seeds of several plant species can germinate regardless of this stimulus. Whereas the molecular mechanisms triggered by light for seed germination are well understood, the ones permitting plants to germinate in the dark are still vague mostly due to the lack of suitable model systems. Here we employ Cardamine hirsuta, a close Arabidopsis relative, as a powerful model system to uncover the molecular mechanisms underlying light-independent germination. Comparing Cardamine and Arabidopsis we show that the maintenance of the pro-germination hormone Gibberellin (GA) levels prompt Cardamine seeds to germinate in dark and light conditions. Via genetic and molecular biology experiments, we show that the Cardamine DOF transcriptional repressor DOF AFFECTING GERMINATION 1 (ChDAG1), homologous to the Arabidopsis DAG1 transcription factor, is involved in this process functioning to mitigate GA levels via negative regulation of ChGA3OX1 and ChGA3OX2 gibberellin biosynthetic genes, independently of light conditions. We also demonstrate that this mechanism is likely to be conserved in other Brassica species capable of germinating in dark conditions, such as Lepidium sativum and Camelina sativa. Our data support the proposal that Cardamine is a new model system suitable for light-independent germination studies. Exploiting this system we also resolved a long-time question about the mechanisms controlling the light-independent germination in plants, opening new frontiers for future studies., (Copyright © 2025 The Author(s). Published by Elsevier Inc. All rights reserved.)

This study investigates the effect of continuous blue light (CBL) treatment on quality-related metabolites, focusing on ascorbic acid (AsA) accumulation in hydroponically grown Eruca vesicaria (L.). Plants were subjected to CBL treatment, consisting of 24-h exposure to constant-intensity blue light (48 μmol m -2 s -1 ) and 12-h exposure to the remaining spectrum (192 μmol m -2 s -1 ). The activities of key enzymes in AsA biosynthesis and recycling were analyzed, including L-galactono-1,4-lactone dehydrogenase (GalLDh), monodehydroascorbate reductase (MDhAR), dehydroascorbate reductase (DhAR), and ascorbate peroxidase (APX). The results showed a significant increase in AsA accumulation of 65.9% during the "day" and 69.1% during the "night" phases under CBL compared to controls. GalLDh activity increased by 20% during the "day phase" in CBL-treated plants. APX activity also rose significantly under CBL conditions, by 101% during the "day" and 75.6% during the "night". However, this did not affect dehydroascorbic acid levels or the activities of MDhAR and DhAR. These findings highlight the potential of tailored light treatments to enhance the nutraceutical content of horticultural species, offering valuable insights for sustainably improving food quality in controlled-environment agriculture (CEA) systems and understanding the roles of blue light in ascorbic acid biosynthesis.

The history of research on gravitropism has been largely confined to the primary root-shoot axis and to understanding how the typically vertical orientation observed there is maintained. Many lateral organs are gravitropic too and are often held at specific non-vertical angles relative to gravity. These so-called gravitropic setpoint angles (GSAs) are intriguing because their maintenance requires that root and shoot lateral organs are able to effect tropic growth both with and against the gravity vector. This chapter describes methods and considerations relevant to the investigation of mechanisms underlying GSA control., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.)

Auxin is a simple molecule with a remarkable ability to control plant growth, differentiation, and morphogenesis. The mechanistic basis for this versatility appears to stem from the highly complex nature of the networks regulating auxin metabolism, transport and response. These heavily feedback-regulated and inter-dependent mechanisms are complicated in structure and complex in operation giving rise to a system with self-organizing properties capable of generating highly context-specific responses to auxin as a single, generic signal.