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Highlights: [•] Mutant line bcs is isolated in the F3 generation of chemically mutagenized zebrafish. [•] Calcein and alcian blue staining is effective to detect bone development defects. [•] Bcs delays axial skeletal calcification, but does not affect cartilage development. [Copyright &y& Elsevier]

Abstract: The zebrafish exhibits an enhanced capability of regenerating most of its adult tissues. In this study, we examine the roles of light illumination and functional expression of mitosis-specific gene wee1 on adult zebrafish caudal fin regeneration after amputation. During the first 3days post-amputation (dpa), the caudal fin regenerate rapidly in the day but slowly at night when the fish are kept in a normal light–dark cycle (LD) condition. However, this day–night rhythm of fin regeneration is not seen when the fish are kept in constant dark (DD), constant light (LL), or in fish in which the circadian rhythms are disrupted by random light (RL) exposures. The rate of fin growth reaches the peak levels at 2.5dpa in LD, but is delayed when the fish are kept in DD, LL or RL conditions. In zebrafish in which the expression of wee1 is blocked by morpholinos, regeneration of the caudal fin is affected. Interestingly, the expression of wee1 also displays robust circadian rhythms. Together, the data suggests that fin regeneration in zebrafish is regulated by both environmental cues and functional gene expressions. Alterations in lighting conditions or inhibition of wee1 expression result in decreases in fin regeneration after injury. [Copyright &y& Elsevier]

In this study, the role of soaking beans in a sodium citrate solution (a cation chelator) at pH = 4.4 and 41 °C in directing/improving the cooking behaviour of common beans was explored. The cooking behaviour of the pre-soaked red kidney beans was determined and the corresponding changes of phytate, minerals, starch, protein and pectin were quantified. Soaking beans in citrate buffer could accelerate softening of the beans during cooking in deionised water while subsequent cooking of beans in this buffer had a limited additional effect on softening compared to cooking in deionised water. Phytate hydrolysis during soaking in citrate buffer results in a release of Mg2+ and Ca2+. Both cations were leached into the soaking medium, higher amounts being observed for Mg2+ release to the soaking media because of the lower affinity of Mg2+ for pectin. It was observed that the pectin solubilisation rate in beans treated by sodium citrate buffer was positively correlated to bean softening. All of these results point out that soaking in a citrate buffer prohibits pectin Ca2+ cross linking therefore enhancing pectin solubilisation and thus increasing the bean softening rate constants during cooking, while starch and protein were not responsible for texture evolution. • Soaking beans in sodium citrate buffer improved cookability of beans. • Mg2+/Ca2+ in cotyledons and seed coats released to the soaking/cooking medium. • Citrate buffer (pH 4.4) increased pectin solubilisation promoting bean softening. • Starch gelatinisation and protein denaturation did not play a major role in bean softening. [ABSTRACT FROM AUTHOR]