Biology subjects

Amiri, E.

Publications and source records attributed to Amiri, E..

4 recordsLinked to original sources

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

Genomic Resources for the Scuttle Fly Megaselia abdita: A Model Organism for Comparative Developmental Studies in Flies

The order Diptera (true flies) holds promise as a model taxon in evolutionary developmental biology due to the inclusion of the model organism, Drosophila melanogaster, and the ability to cost-effectively rear many species in laboratories. One of them, the scuttle fly Megaselia abdita (Phoridae) has been used in evolutionary developmental biology for 30 years and is an excellent phylogenetic intermediate between fruit flies and mosquitoes but remains underdeveloped in genomic resources. Here, we present a de novo chromosome-level assembly and annotation of M. abdita and transcriptomes of 9 embryonic and 4 postembryonic stages. We also compare 9 stage-matched embryonic transcriptomes between M. abdita and D. melanogaster. Our analysis of these resources reveals extensive chromosomal synteny with D. melanogaster, 28 orphan genes with embryo-specific expression including a novel F-box LRR gene in M. abdita, and conserved and diverged features of gene expression dynamics between M. abdita and D. melanogaster. Collectively, our results provide a new reference for studying the diversification of developmental processes in flies.

developmental biology↗

bioRxiv2022

Social Regulation of Egg Size Plasticity in the Honey Bee is Mediated by Cytoskeleton Organizer Rho1

Egg size plasticity represents an adaptive reproductive strategy in numerous organisms, including the honey bee, Apis mellifera. However, the proximate causation of this plasticity and egg size in general is unknown. We show that honey bee queens predictably and reversibly adjust egg size in response to their colony size and that this plasticity is an active response to the queens perception of colony size instead of a consequence of egg laying rate. The egg size increase involves changes of 290 ovarian proteins, mostly related to increased energy metabolism, protein transport, and cytoskeleton functions. Spatio-temporal expression analysis of the small GTPase Rho1 indicates its central role in egg size regulation, which we confirm by RNAi-mediated gene knock-down and expression analyses. The molecular adjustments that promote maternal investment of honey bee queens in response to their social environment thus reveal a novel mechanism of egg size regulation.

evolutionary biology↗

bioRxiv2021

Cryptic costs of viral infection in a model social insect

Declining insect populations emphasize the importance of understanding the drivers underlying reductions in insect fitness. Here, we investigated viruses as a threat to social insect reproduction, using honey bees as a model species. We report that in a sample of N = 93 honey bee (Apis mellifera) queens from nine beekeeping operations across a wide geographic range, high levels of natural viral infection are associated with decreased ovary mass. We confirmed this finding in an independent sample of N = 54 queens. Failed (poor quality) queens displayed higher levels of viral infection, reduced sperm viability, smaller ovaries, and altered ovary protein composition compared to healthy queens. We experimentally infected queens with Israeli acute paralysis virus (IAPV) and found that the ovary masses of IAPV-injected queens were significantly smaller than control queens, demonstrating a causal relationship between viral infection and ovary size. Queens injected with IAPV also had significantly lower expression of vitellogenin, the main source of nutrition deposited into developing oocytes, and higher levels of heat-shock proteins (HSPs), which are part of the honey bees antiviral response. This work together shows that viral infections occurring naturally in the field are compromising queen reproductive success.

systems biology↗