Biology subjects

Tang, J. J.

Publications and source records attributed to Tang, J. J..

3 recordsLinked to original sources

bioRxiv2026

Drosophila Heat Shock Factor (HSF) Regulates Developmental Growth by Maintaining the Basal Expression of HSP83/HSP90

The heat shock transcription factor HSF1 is best known as a master regulator of the proteotoxic stress response, yet its functions in animal development remain incompletely defined. In Drosophila melanogaster, heat shock factor (HSF) is essential for viability, but the mechanisms by which it promotes development are unclear. Here, we show that Hsf null larvae arrest at the early 2nd instar stage and exhibit a significant reduction in basal levels of the chaperone HSP83/HSP90. Tissue-specific knockdown of Hsf revealed widespread and organ-specific requirements, including defects in endoreplication and cell growth in larval prothoracic and salivary glands, adult wing defects following larval imaginal disc perturbation, follicle degeneration in the ovary, and melanotic tumor upon hemocyte depletion. In these tissues, loss of HSF typically leads to reduced HSP83 levels, and restoration of HSP83 expression partially or fully rescues these defects. These findings identify HSP83 as a critical downstream effector of HSF and demonstrate that HSF promotes development largely by maintaining basal chaperone expression. Together, our results establish HSF as a key regulator of developmental progression and highlight a central role for proteostasis in supporting tissue growth under non-stress conditions.

developmental biology↗

bioRxiv2025

C. elegans astrocytes mature in two phases from lineally distinct progenitors through CEH-43/DLX-mediated convergent transcription

Mammalian radial glia can remodel to become astrocytes, which acquire common transcriptional states despite spatially and lineally distinct origins. To uncover molecular programs driving convergent radial-glia-to-astrocyte transformation, we investigated development of C. elegans CEPsh astrocytes, which also arise from distinct progenitors without cell division. Using lineage-restricted single-cell RNA sequencing, we delineate a two-phase program for CEPsh astrocyte formation. Transcriptionally disparate nascent CEPsh glia rapidly acquire a common radial-glia-like state, facilitating nerve ring (brain) assembly. Subsequently, convergent CEPsh glia upregulate astrocyte-specific gene expression. Both phases require the distal-less transcription factor CEH-43, expressed in CEPsh glia and their progenitors. CEH-43 binds conserved astrocyte-expressed genes, cell-autonomously activating both early and late CEPsh glia-specific gene expression. CEH-43 misexpression is sufficient to induce CEPsh astrocyte reporter expression. We demonstrate that CEH-43 homologs, DLX1/2, are expressed in mouse astrocytes, and comparative transcriptomics reveal additional parallels. Our findings provide a molecular foundation for understanding cell-division-independent radial-glia-to-astrocyte transformation.

neuroscience↗

bioRxiv2020

Canopy parkour: movement ecology of post-hatch dispersal in a gliding nymphal stick insect (Extatosoma tiaratum)

For flightless arboreal arthropods, moving from the understory into tree canopies is cognitively and energetically challenging because vegetational structures present complex three-dimensional landscapes with substantial gaps. Predation risk and wind-induced perturbations in the canopy may further impede the movement process. In the Australian stick insect Extatosoma tiaratum, first-instar nymphs hatch on the forest floor and disperse toward tree canopies in the daytime. Here, we address such vertical movements and associated sensory cues in E. tiaratum nymphs. Newly hatched nymphs ascend with high endurance, travelling >100 m within 60 minutes. Navigation toward open canopies is underpinned by negative gravitaxis, positive phototaxis, and visual responses to vertically oriented contrast patterns. Nymphal E. tiaratum also use directed jumping to cross air gaps, and respond to tactile stimulation and potential threat with a self-dropping reflex, resulting aerial descent. Post-hatch dispersal in E. tiaratum thus consists of visually mediated displacement both on vegetational structures and in the air; within the latter context, gliding is then an effective mechanism enabling recovery after predator- and perturbation-induced descent. These results further support the importance of a diurnal niche, in addition to the arboreal spatial niche, in the evolution of gliding in wingless arboreal invertebrates. Summary statementTo effectively disperse into canopies, ground-hatched stick insects use gravity and visual cues to navigate during midday, jump to cross air gaps and respond to threat or perturbation with self-dropping.

animal behavior and cognition↗