Harris, J. W. | bioRxiv Science

bioRxiv2025

Honey Bee Queen Susceptibility to Viral Infection Varies Across Developmental Stages in Queen Rearing Operations

Viruses are a large class of honey bee pathogens that negatively affect colony health, yet their prevalence and transmission dynamics in commercial queen production operations remain poorly understood. To address this gap, we conducted a series of controlled queen monitoring experiments and surveys to understand the prevalence and viral loads of seven viruses across developmental stages of queens, drones, royal jelly, and workers from associated colonies. All viruses except SBV were detected, with BQCV, DWV-B, and LSVs showing consistently high prevalence. Eggs were frequently infected with LSVs, DWV-B, and CBPV, suggesting vertical virus transmission, and highlighting the importance of selecting healthy breeder queens. BQCV, on the other hand, dominated in queen larvae, pupae, and adult stages. Mated queens, particularly those maintained in bank colonies, exhibited higher prevalence and viral loads than virgin queens, with DWV-B and BQCV being most abundant. Worker bees from bank colonies also showed slightly higher viral loads compared to other colonies, indicating potential risks associated with queen banking. Drone samples revealed high BQCV and DWV-B prevalence, indicative of their potential role in venereal transmission. The results from hierarchical clustering and correlation analyses provided evidence that viral profiles of queens did not necessarily match those of their resident colonies, highlighting complex viral transmission dynamics. Collectively, these findings provide novel insights into virus transmission dynamics during queen production and emphasize the need to improve queen health. Author summaryHoney bee queen failure is a frequent challenge in beekeeping operations, and viral infections are increasingly recognized as an important contributor. Since no chemical therapeutics are available for managing viral diseases in honey bees, understanding routes of viral transmission is critical for developing strategies to minimize infections. However, the diversity of viruses infecting queens, their prevalence, and their main transmission routes have not been systematically investigated within the queen production industry. Therefore, in this study we investigated viral prevalence, loads, and transmission dynamics in commercial queen production operations, using a diverse array of samples, including queens at different developmental stages, worker bees from associated colonies, drones, and Varroa mites. Our analysis consistently indicates that vertical transmission from infected breeder queens, natural mating, and bank colonies with high Varroa infestations are key points where queens are most vulnerable and become infected with viruses. These findings offer novel insights into virus transmission dynamics in queens, emphasizing the importance of selecting healthy breeder queens and controlling Varroa infestations in drone source and bank colonies.

pathology↗

bioRxiv2025

Live-cell NanoBRET assay to measure AKT inhibitor binding to conformational states of AKT

AKT is the main protein kinase of the PI3K-AKT pathway, interacting with over one hundred protein partners to facilitate cellular processes that allow cancer cells to survive and proliferate. It is an attractive target due to its control over many cellular outputs. However, ATP-competitive and allosteric AKT inhibitors have performed poorly in clinical trials. AKT inhibitor interactions with AKT are multi-faceted and influence the catalytic activity of AKT, its conformation, its ability to interact with binding partners, and its phosphorylation state. Therefore, a better understanding of how these inhibitors influence these parameters is needed, especially in a cellular context. Using a live-cell NanoBRET target engagement assay to query the binding of AKT inhibitors to all isoforms of AKT, we found that ATP-competitive inhibitors bind similarly across all three isoforms, and allosteric inhibitors bind more heterogeneously. Further, assaying gain-of-function pathological mutants and myristoylated active versions of all AKT isoforms revealed that T308 phosphorylation enhances the binding of ATP-competitive inhibitors. We found that this phosphorylation is a good indicator of cell viability sensitivity to ATP-competitive inhibitors when comparing effects on known resistant and sensitive triple-negative breast cancer cell lines. Taken together, this assay is useful for screening new AKT inhibitors, and these findings represent important considerations in developing the next generation of AKT inhibitors.

biochemistry↗

bioRxiv2019

A rectal cancer model establishes a platform to study individual responses to chemoradiation

Rectal cancer (RC) is a challenging disease to treat that requires chemotherapy, radiation, and surgery to optimize outcomes for individual patients. No accurate model of RC exists to answer fundamental research questions relevant to individual patients. We established a biorepository of 32 patient-derived RC organoid cultures (tumoroids) from patients with primary, metastatic, or recurrent disease. RC tumoroids retained molecular features of the tumors from which they were derived, and their ex vivo responses to clinically relevant chemotherapy and radiation treatment correlate well with responses noted in individual patients tumors. Upon engraftment into murine rectal mucosa, human RC tumoroids gave rise to invasive rectal cancer followed by metastasis to lung and liver. Importantly, engrafted tumors closely reflected the heterogenous sensitivity to chemotherapy observed clinically. Thus, the biology and drug sensitivity of RC clinical isolates can be efficiently interrogated using an organoid-based, in vitro platform coupled with endoluminal propagation in animals.

cancer biology↗