Nanocarrier-based chemotherapy is one of the most efficient approaches for the treatment of cancer, and hence, the design of new nanocarriers is very important. Herein, the design of a new class of physically cross-linked nanoparticles (nanogel) solely made of biomolecules including DNA, protein, and biotin as a nanocarrier for the targeted cancer therapy is reported. A specific molecular recognition interaction between biotin and streptavidin is explored for the cross-linking of a DNA nanostructure for the crafting of a nanogel. The most unique structural features of nanogels include the following: (i) excellent biocompatibility, (ii) decoration of the nanogel surface with biotin and streptavidin randomly that allowed the integration of aptamer DNA onto the surface of the nanostructure through the biotin–streptavidin interaction, (iii) high doxorubicin encapsulation efficacy through the intercalation of doxorubicin inside the DNA duplex, and (iv) stimuli responsiveness. The selective uptake of a doxorubicin-loaded nanogel by aptamer-receptor-positive cell lines (CCRF-CEM and HeLa) and its delivery inside the target cells are demonstrated. The selective uptake of the nanogel by CCRF-CEM and HeLa cells is attributed to the specific interaction between the aptamer DNA decorated on the surface of the nanogel with the PTK7 receptor overexpressed on CCRF-CEM and HeLa cell lines. These results imply that the nanogel obtained from the self-assembly of biomolecules would be ideal for the crafting of nanocarriers for targeted cargo delivery applications.

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We discovered nocturnal colour vision in the Asian giant honeybee Apis dorsata— a facultatively nocturnal species — at mesopic light intensities, down to half-moon light levels (approx. 10 −2 cd m −2 ). The visual threshold of nocturnality aligns with their reported nocturnal activity down to the same light levels. Nocturnal colour vision in A. dorsata is interesting because, despite being primarily diurnal, its colour vision capabilities extend into dim light, while the ‘model’ European honeybee Apis mellifera is reported to be colour-blind at twilight. By employing behavioural experiments with naturally nesting A. dorsata colonies, we show discrimination of the trained colour from other stimuli during the day, and significantly, even at night. Nocturnal colour vision in bees has so far only been reported in the obligately nocturnal carpenter bee Xylocopa tranquebarica. The discovery of colour vision in these two bee species, despite differences in the extent of their nocturnality and the limitations of their apposition compound eye optics, opens avenues for future studies on visual adaptations for dim-light colour vision, their role in pollination of flowers at night, and the effect of light pollution on nocturnal activity in A. dorsata, a ubiquitous pollinator in natural, agricultural and urban habitats in the Asian tropics and sub-tropics.

Ants, being ubiquitous, aggressive, and top predators, play a predominant role in terrestrial ecosystems. Jumping spiders are another prominent invertebrate predator that are present in similar habitats as that of ants. Most jumping spiders are thought to avoid ants, yet little is known if they discriminate among them. In this study we examined the response of jumping spider genus Plexippus towards three different ant species (Oecophylla smaragdina, the weaver ants;Camponotus sericeus the golden-back carpenter ants, and Leptogenys processionalis, the procession ants). In a behavioral assay that excluded tactile and chemical cues, we tested if spiders distinguish the three ants by visual cues alone. We recorded and analysed behaviors such as 'look', 'approach', 'stalk', 'attack', and 'avoidance' by spiders towards ants. Our results show that the three ants differ in their color, movement and aggressive behavior. Spiders gave 'short looks' to live ants, suggesting movement is important in detecting ants. Furthermore, spiders gave significantly more 'long looks' to procession and golden-back ants compared to weaver ants. Spiders approached, stalked and attacked procession ants more compared to weaver ants.Numerous jumping spiders and ants overlap in their habitat, and it is advantageous to selectively avoid some ants over others. Our results suggests that jumping spiders can indeed distinguish ants that co-occur in their habitat by visual cues alone, however, the precise nature of visual cues warrants further studies.