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In this study, the complete mitogenome sequence of the Goniopora lobata has been sequenced using next-generation sequence method. The overall of G. lobata mitogenome is 25.72% for A, 13.59% for C, 23.42% for G, and 37.27% for T, as well as 37.01% for low GC. The assembled mitogenome, consisting of 18770 bp, has 13 unique protein-coding genes (PCGs), three transfer RNA genes, and two ribosomal RNA genes. The complete mitogenome of G. lobata provides essential and important DNA molecular data for further phylogenetic and evolutionary analysis of stony coral phylogeny.

Coral has strong regeneration ability, which has been applied for coral production and biodiversity protection via tissue ball (TB) culture. However, the architecture, morphological processes, and effects of environmental factors on TB formation have not been well investigated. In this study, we first observed TB formation from the cutting tentacle of scleractinia coral Goniopora lobata and uncovered its inner organization and architecture by confocal microscopy. We then found that the cutting tentacle TB could self-organize and reform a solid TB (sTB) in the culture media. Using chemical drug treatment and dissection manipulation approaches, we demonstrated that the mechanical forces for bending and rounding of the cutting fragments came from the epithelial cells, and the cilia of epithelial cell played indispensable roles for the rounding process. Environmental stress experiments showed that high temperature, not CO-induced acidification, affected TB and sTB formation. However, the combination of high temperature and acidification caused additional severe effects on sTB reformation. Our studies indicate that coral TB has strong regeneration ability and therefore could serve as a new model to further explore the molecular mechanism of TB formation and the effects of environmental stresses on coral survival and regeneration. [ABSTRACT FROM AUTHOR]

A simple, non-destructive and objective method is developed and evaluated to quantify bleaching or colour change in coral in terms of its percent whiteness. Digital photos of coral colony were taken with a photoquadrat marked with black and white bands around a metal frame to serve as colour references. Photos taken were then converted to a black and white grey-scale and intensities of the coral colour were determined with reference to this grey-scale using computer image analytical technique. A completely bleached coral gave an estimated percent whiteness that is close to 100%, an estimate that agrees well with the visual image of a bleached coral. The percent whiteness estimates were found not to be significantly affected by different levels of irradiance and turbidites under simulated conditions. Colour change in seven common Hong Kong coral species were further evaluated in situ and shown to exhibit an increasing trend of percent whiteness from January (winter) to April 2012 (spring), reflecting an increasing degree of bleaching. Using Goniopora lobata as an experimental species, estimated percent whiteness was shown to be negatively correlated with its zooxanthellae density and chlorophyll a concentration. This suggests that this method could allow repeated monitoring of individual coral colony over time to detect subtle variations in its colour as a general assessment of its health. Furthermore, reference percent whiteness of different coral species can be standardized for comparison of colour change over time to identify the critical level of percent whiteness that is associated with bleaching. Thus, this method should prove to be an easy and objective tool for rapid field assessment of coral health. [ABSTRACT FROM AUTHOR]

In this study, the complete mitogenome sequence of the Goniopora lobata has been sequenced using next-generation sequence method. The overall of G. lobata mitogenome is 25.72% for A, 13.59% for C, 23.42% for G, and 37.27% for T, as well as 37.01% for low GC. The assembled mitogenome, consisting of 18770 bp, has 13 unique protein-coding genes (PCGs), three transfer RNA genes, and two ribosomal RNA genes. The complete mitogenome of G. lobata provides essential and important DNA molecular data for further phylogenetic and evolutionary analysis of stony coral phylogeny. [ABSTRACT FROM AUTHOR]

Hermatypic-zooxanthellate corals track the diel patterns of the main environmental parameters - temperature, UV and visible light - by acclimation processes that include biochemical responses. The diel course of solar radiation is followed by photosynthesis rates and thereby elicits simultaneous changes in tissue oxygen tension due to the shift in photosynthesis/respiration balance. The recurrent patterns of sunlight are reflected in fluorescence yields, photosynthetic pigment content and activity of the two protective enzymes superoxide dismutase (SOD) and catalase (CAT), enzymes that are among the universal defenses against free radical damage in living tissue. All of these were investigated in three scleractinian corals: Favia favus, Plerogyra sinuosa and Goniopora lobata. The activity of SOD and CAT in the animal host followed the course of solar radiation, increased with the rates of photosynthetic oxygen production and was correlated with a decrease in the maximum quantum yield of photochemistry in Photosystem II (PSII) (ΔF′/Fm′). SOD and CAT activity in the symbiotic algae also exhibited a light intensity correlated pattern, albeit a less pronounced one. The observed rise of the free-radical-scavenger enzymes, with a time scale of minutes to several hours, is an important protective mechanism for the existence and remarkable success of the unique cnidarian-dinoflagellate associations, in which photosynthetic oxygen production takes place within animal cells. This represents a facet of the precarious act of balancing the photosynthetic production of oxygen by the algal symbionts with their destructive action on all living cells, especially those of the animal host. [ABSTRACT FROM AUTHOR]