Gaohong Wang

Chinese Academy of Sciences, Institute of Hydrobiology

Chroococcidiopsis spp. can withstand extremely harsh environments, including a Mars-like environment. However, studies are lacking on the molecular mechanisms of Chroococcidiopsis sp. surviving in Mars-like environments. In the HH-21-5 mission, the desert cyanobacterium Chroococcidiopsis sp. was exposed to a Mars-like environment (near space; 35 km...

The protective ozone layer is continually depleting owing to an increase in the levels of solar UV-B radiation, which has harmful effects on organisms. Algae in desert soil can resist UV-B radiation, but most research on the radiation resistance of desert algae has focused on cyanobacteria. In this study, we found that desert green algae, Chlorella...

During the HH-19-2 flight mission of the Chinese Scientific Experimental System, dried Nostoc sp. cells were exposed to the stratosphere environment (32,508 m altitude) for 3 h and 22 min. The atmospheric pressure, temperature, relative humidity, and ionizing and non-ionizing radiation levels at that altitude are similar to those on the surface of...

Desert was considered terrestrial analogues of Mars. In this study, dried cells of desert green algae Chlorella were exposed to Mars-like near-space environment using high-altitude scientific balloons. We found that while a majority of Chlorella cells survived, they exhibited considerable damage, such as low photosynthetic activity, reduced cell gr...

The regeneration of induced biological soil crusts (IBSCs) is regarded as an effective strategy for combating desertification. Three types of BSCs, namely, cyanobacterial, lichen and moss, are well-accepted as the main succession phases and are hypothesized to represent a continuous process. Herein, natural BSCs (NBSCs) and IBSCs with accurate ages...

UV radiation is a serious threat to life, and algae have developed highly efficient adaptations to UV radiation through the course of evolution. To date, studies investigating the mechanisms of UV adaptation in algae have focused on physiological regulation and associated protein coding genes, with only a few reports on associated protein non-codin...

Aim: Heat shock is a common stress for life, while algae develops high efficient adaptation ability to heat shock during longtime evolution. Up to date, the researches about the mechanism of heat shock adaptation in algae focus just on physiological regulation and related coding genes, while there are few reports about non-coding genes on it. In th...

Long- term spaceflight needs reliable Biological life support systems (BLSS) to supply astronauts with enough food, fresh air and recycle wasters, but the knowledge about the operation pattern and controlling strategy is rear. For this purpose, a miniaturized enclosed aquatic ecosystem was developed and flown on the Chinese spaceship Shenzhou-8. Th...

Stimulus dependence is a general feature of developing animal sensory systems. In this respect, it has extensively been shown earlier that fish inner ear otoliths can act as test masses as their growth is strongly affected by altered gravity such as hypergravity obtained using centrifuges, by (real) microgravity achieved during spaceflight or by si...

MicroRNAs play an important role in abiotic stress responses in higher plants and animals, but their role in stress adaptation in algae remains unknown. In this study, the expression of identified and putative miRNAs in Chlamydomonas reinhardtii was assessed using quantitative polymerase chain reaction; some of the miRNAs (Cre-miR906-3p) were up-re...

UV radiation of sunlight is one of harmful factors for earth organisms, especially for photoautotrophs because they require light for energy and biomass production. A number of works have already been done regarding the effects of UV-B radiation at biochemical and molecular level, which showed that UV-B radiation could inhibit photosynthesis activi...

The effects of 17-day spaceflight microgravity on the photosynthetic activity of Euglena gracilis were investigated during the SIMBOX mission on board the Chinese Shenzhou-8 spacecraft. We found that microgravity decreased Fv/Fm, while chlorophyll a and carotenoid contents were increased. The fluorescence yields were clearly reduced by microgravity...

In this study model organism Chlamydomonas reinhardtii was used to investigate changes in growth, photosystem II (PSII) activity, pigments and neutral lipids accumulation under different levels of salinity. It was found that the inhibition of salinity on cell growth was depended on salinity levels. The growth rates and the content of chlorophyll a...

The development of Biological Soil Crusts (BSCs) is widely recognized as beneficial to soil fertility due to their contribution to the stabilization of soils and to the increase in their carbon and moisture content. An important role in these processes is played by the extracellular polysaccharidic (EPS) matrix embedding microbial cells and soil pa...

The unicellular green algae Chlamydomonas reinhardtii is a classic model for the study of flagella/cilia and photosynthesis and recently it also has been exploited for producing biopharmaceuticals and biofuel. Due to the low frequency of homologous recombination, reverse genetic manipulation in Chlamydomonas relies mainly on miRNA and siRNA-based k...

Artificial biological soil crusts (ABSCs), formed by inoculating Microcoleus vaginatus Gom. and Scytonema javanicum Born. et Flah. onto the topsoil of desert dunes, proved to be effective tools for the stabilization of moving dunes and promotion of soil fertility. As dominant driving forces in arid habitats, the abiotic environmental conditions of...

The present study investigated the physiological and biochemical characteristics of Scytonema javanicum, a pioneer species isolated from desert biological crusts, under salinity stress. Pigment analysis showed that salinity decreased chlorophyll a and phycocyanin content, while low salinity increased carotenoid concentration and high salinity decre...

Abstract Reproduction and locomotion are essential features of animals that help to facilitate their interaction with the surrounding environment. Previous studies have produced inconsistent results on behavioral response to spaceflight by the model animal Caenorhabditis elegans (C. elegans) in liquid culture. Using standard agar-based nematode gro...

Aphanizomenon flos-aquae (A. flos-aquae), a cyanobacterium frequently encountered in water blooms worldwide, is source of neurotoxins known as PSPs or aphantoxins that present a major threat to the environment and to human health. Although the molecular mechanism of PSP action is well known, many unresolved questions remain concerning its mechanism...

Photosystem efficiency and the characteristic on oxidative stress were examined to elucidate the metabolic responses of Synechocystis sp. PCC 6803 to short-term clinorotation. Results compiled when using clinostat to simulate microgravity for 60 h, showed that clinorotation clearly prohibited the photochemical quantum yield, but promoted the synthe...

The toxicological effects of nanometer titanium dioxide (nano-TiO2) on a unicellular green alga Chlamydomonas reinhardtii were assessed by investigating the changes of the physiology and cyto-ultrastructure of this species under treatment. We found that nano-TiO2 inhibited photosynthetic efficiency and cell growth, but the content of chlorophyll a...

Otolith is the vestibular endorgan that takes part in gravitational signal initiation. Environmental change can leave mark on otolith microstructure. In this study, we use zebrafish from embryo stage of 10hpf to middle larval stage of 12dpf to investigate the effect of microgravity on otolith development. It was found that otoliths size of microgra...

Aquatic ecosystem is a useful means to explore complex interaction among different species, and data got from this kind of system can be used to re-constructer or bio-remedy damaged ecosystem or explore other planet, such as Mars. To deeply investigate interactions of different species in space environment, we established a closed aquatic ecosystem...

We had investigated the colonization of soils in Mars-like environments in Chinese deserts by phototrophs. Some extreme cyanobacteria and algae strains were collected and mass-cultured in desert regions to investigated their ability to artificially form desert crusts. These crusts had the capacity to resist sand storm erosion after just 15 days of...

A lab mini-module of Closed Aquatic Ecosystem consisting of Chlorella pyrenoidosa and Bulinus australianus was constructed to study the effect of nutrient limitation on long term operation. A series of tests were taken, the first introduced was consumer part Bulinus australianus, the second nutrient introduced was inorganic carbon source, organic c...

Simulated microgravity (SMG) can inhibit proliferation and enhance microcystin production of Microcystis aeruginosa. We investigated the role of nitric oxide (NO) in regulating the SMG induced changes of proliferation, photochemical system II photochemical activity, pigment, soluble protein and microcystin production in M. aeruginosa. M. aeruginosa...

The effects of 20 days clinorotation on cellular struc-ture, photosynthetic activity, and the carbohydrate and astaxanthin metabolism of Haematococcus pluvialis pro-vide insights in algal cell adaption. Light micrographs showed the cell shape appeared abnormal and the volume became smaller than the ground control. Ultrastructure analysis revealed t...

Some phytoplankton can be regarded as possible candidates in the establishment of Controlled Ecological Life Support System (CELSS) for some intrinsic characteristics, the first characteristic is that they should grow rapidly, secondly, they should be able to endure some stress factors and develop some corresponding adaptive strategies; also it is...

Stimulus dependence is a general feature of developing sensory sytems. It has been shown earlier that the growth of otoliths of late-stage Cichlid fish (Oreochromis mossambicus) and Zebrafish (Danio rerio) was slowed down by hypergravity, whereas microgravity during spaceflight yielded an opposite effect, i.e., larger than 1 g otoliths, in Swordtai...

In the present study, we investigated the effects of sa-linity stress, one of the main stress in polluted water bodies, on the photosynthetic activity of Wolffia arrhiza. High salinity stress (1-4%) significantly decreased photo-synthetic CO 2 assimilation activity, while the chlorophyll a, chlorophyll b and carotenoid contents were not affected af...

Phytoplankton samples were taken weekly from September 2009 to November 2010 in Lake Erhai. The purpose was to obtain detailed information about the composition variations in the phytoplankton community during the serious drought in 2009 - 2010 and to determine the driving force for the succession of the dominant genera. A total of 147 phytoplankto...

Cyanobacteria are capable of tolerating environmental extremes. To survive in extreme environments, cyanobacteria have developed the capability to adapt to a variety of stresses. For example, cyanobacteria have adopted a number of strategies with which to survive UV stress, including expression of UV-screening pigments and antioxidant systems. We h...

Stimulus dependence is a general feature of all developing sensory systems. Concerning the vestibular organ of fish, it has been shown earlier that the growth of inner ear otoliths of developing Cichlid fish (Oreochromis mossambicus) and Zebrafish (Danio rerio) is slowed down by increased gravity (hypergravity) as an adaptation. Several studies pro...

The higher plant Wolffia arrhiza is regarded to be well suited concerning the provision of photosynthetic products in the cycle of matter of a Controlled Ecological Life Support System (CELSS) to be established in the context of extraterrestrial, human-based colonization and long-term space flight. Since UV radiation is one major extraterrestrial e...

Recent researches indicated that microgravity can increase pathogenic bacteria virulence. We presumed that microgravity might affect the toxin production of toxic cyanobacteria too. Microcystis aeruginosa PCC7806 was chosen as the model organism to investigate the effects of simulated microgravity (SMG) on the growth and toxin production of toxic c...

A lot of aquatic organisms could be regarded as suitable candidates par excellence in the establishment of CELSS, since they are relatively easy and fast to grow and resistant to changes in environmental condition as well as providing nutritious, protein-and vitamin-rich foods for the crew, which can fulfill the main functions of CELSS, including s...

Cyanobacteria are renowned for tolerating extremes of desiccation, UV radiation, freezethaw cycles, hypersalinity and oligotrophy, which make them as candidate par excellence for terraforming in extraterrestrial planet. Recently Raman spectrum was applied to study the biochemical information changes in different field of life science. In this study...

UV-B-induced oxidative damage and the protective effect of exopolysaccharides (EPS) in Microcoleus vaginatus, a cyanobacterium isolated from desert crust, were investigated. After being irradiated with UV-B radiation, photosynthetic activity (Fv/Fm), cellular total carbohydrates, EPS and sucrose production of irradiated cells decreased, while reduc...

A closed aquatic ecosystem (CAES) was developed to study the effects of microgravity on the function of closed ecosystems aboard the Chinese retrieved satellite and on the spacecraft SHENZHOU-II. These systems housed a small freshwater snail (Bulinus australianus) and an autotrophic green algae (Chlorella pyrenoidosa). The results of the test on th...

Studies on the colonization of environmentally extreme ground surfaces were conducted in a Mars-like desert area of Inner Mongolia, People's Republic of China, with microalgae and cyanobacteria. We collected and mass-cultured cyanobacterial strains from these regions and investigated their ability to form desert crusts artificially. These crusts ha...

In this study, we found that UV-B radiation decreased photosynthetic activity and boosted lipid peroxidation of desert Nostoc sp., and exogenous chemicals (ascorbate acid (ASC), N-acetylcysteine (NAC), and sodium nitroprusside (SNP)) had obvious protective effects on photosynthesis and membranes under UV-B radiation. High-concentration SNP boosted...

Fish has been proved to be a suitable vertebrate to study gravity effecting on body growth. When exposed to simulated microgravity, zebrafish embryos were found rapidly hatched with very small yolk-sac and pale color appearance from day 2. At hatch, the fish had larger body length (p¡0.001) and well developed swimming ability, it could floating fre...

Controlled Ecological Life Support Systems (CELSS) is very important for long-term manned space flight. Aquatic organism was regarded to be suitable for this study because of their great adaptation to the weightless condition which approximate to their wild condition in water. In order to study of operation of CELSS in space, the first step is to c...

UV radiation is one major environmental stress for growth of Wolffia arrhiza which is regarded as a good candidate producer for establishing CELSS during extraterrestrial colonization and spaceflight. In this study, we found that UVB radiation inhibited photosynthetic CO2 assimilation activity significantly, and the content of chlorophyll a, chloro...

A Closed Aquatic Ecosystem (CAES) was developed to study on performance of closed ecosystems for three month as a preparation for future spaceflight experiments. The system housed three small freshwater snails (Bulinus australianus) and autotrophic green algae (Chlorella pyrenoidosa) in a 500mL box with light and temperature control. The special se...

The different forms of cyanobacterial bio-substances on the growth and photosynthetic activity of submerged macrophyte Ceratophyllum oryzetorum Kom was investigated in present study. Results showed that all kinds of cyanobacterial bio2substances could enhance the growth of C. oryzetorum Kom. differently. Compared with the control , the plant length...

UV radiation is one of many harmful factors found in space that are detrimental to organisms on earth in space exploration. In the present work, we examined the role of antioxidant system in Nostoc sphaeroides Kütz (Cyanobacterium) and the effects of exogenously applied antioxidant molecules on its photosynthetic rate under UV-B radiation. It was f...

The effects of salt stress on carbohydrate metabolism in Microcoleus vaginatus Gom., a cyanobacterium isolated from desert algal crusts, were investigated in the present study. Extracellular total carbohydrates and exopolysaccharides (EPS) in the culture medium produced by M. vaginatus increased significantly during the growth phase and reached a m...

Man-made desert algal crusts were constructed on a large scale (3000m2) in Inner Mongolia, China. Microcoleus vaginatus was mass cultivated and inoculated directly onto unconsolidated sand dune and irrigated by automatic sprinkling micro-irrigation facilities. The crusts were formed in a short time and could resist the erosion of winds and rainfall...

A strain of microalgae (Anabaena siamensis) had been cultured in a miniaturized bioreactor during a retrievable satellite flight for 15 days. By means of remote sensing equipment installed in the satellite, we gained the growth curve of microalgae population in space every day in real time. The curve indicated that the growth of microalgae in space...

In order to study the effect of microgravity on the operation of Closed Ecosystem A two-element Closed Aquatic Ecosystem CAES were established by microalgae Chlorella pyrenoidosa and snail Bulinus australianus By remote sensing to investigate the two-element Closed Aquatic Ecosystem CAES on spacecraft SHENZHOU- the real-time data of operation of CA...

Zebrafish is an important model for vertebrate developmental biology In this study the zebrafish were exposed to normal gravity and 5 g at stages of 3dpf and 6dpf respectively to determine the damage of hyper-gravity to fish growth and morphological development of otoliths of larval zebrafish at different stages Fish growth was calculated by total...

Daily intake and accumulation of microcystins (MCYSTs, MCs) in silver carp (Hypophthalmichthys molitrix) were investigated under lab conditions by feeding the fish exclusively with fresh toxic Microcystis bloom at a density of 6×109 algal cells L-1. The medial lethal dose (LD50) of microcystin-LR to silver carp was estimated to be 270 μg kg-1 body-...

To study the effect of spaceflight and radiation on the photosynthetic system of microalgae. Nostoc sphaewides Kütz was brought on board retrievable satellite or irradiated with 5000 Gy γ ray from 60Co and cultured in dark as the control. Survival rate, photosynthetic activity, ration of photosynthetic pigment and ultrastructure of algal were obser...

Microcystins are cyclic heptapeptide hepatoxins produced by cyanobacteria. It has been shown that microcystins have adverse effects on animals and on plants as well. Previous researches also indicated that microcystins were capable of inducing oxidative damage in animals both in vivo and in vitro. In this study, tobacco BY-2 suspension cell line wa...

The photosynthetic activities between two main developmental stages, colony and hormogonium, of the edible cyanobacteriumNostoc sphaeroides Kützing, were compared. Hormogonia have a higher content of chlorophyll than that of colonies. It showed that the ratios of phycocyain (PC), allophycocyain (APC) and phycoerythrocyanin (PEC) in hormogonia and c...

Changing the ratio of light-harvesting pigments was regarded as an efficient way to improve the photosynthesis rate in microalgae, but the underlying mechanism is still unclear. In the present study, a mutant of Anabeana simensis (called SP) was selected from retrieved satellite cultures. Several parameters related with photosynthesis, such as the...

Hormogonium, which was thought to play an important role in the dispersal and survival of these microorganisms in their natural habitats, is a distinguishable developmental stage of heterocystous cyanobacteria. The present study examined the effects of different light conditions and sugars on the differentiation of Nostoc sphaeroides Kützing to the...

It was found that reactive oxygen species in Anabaena cells increased under simulated microgravity provided by clinostat. Activities of intracellular antioxidant enzymes, such as superoxide dismutase, catalase were higher than those in the controlled samples during the 7 days' experiment. However, the contents of glutathione [correction of gluathio...

Using remote sensing technique, we investigated real-time Nostoc sphaeroides Kütz (Cyanobacterium) in Closed System under microgravity by SHENZHOU-2 spacecraft in January 2001. The experiments had 1 g centrifuges in space for control and ground control group experiments were also carried out in the same equipments and under the same controlled cond...

A simple Closed Aquatic Ecosystem (CAES) consisting of single-celled green algae (Chlorella pyrenoidosa, producer), a spiral snail (Bulinus australianus, consumer) and a data acquisition and control unit was flown on the Chinese Spacecraft SHENZHOU-II in January 2001 for 7 days. In order to study the effect of microgravity on the operation of CAES,...

Objective. To provide direct evidences for effects of microgravity on structure and function of plasma membrane. Method. Malondialdehyde (MDA) content was examined on the basis of quantitative reaction of both MDA and thiobarbituric acid (TBA), and electrolyte leaking was determined with conductometer model DDS-11A. Result. Experiments showed that...