Julia Grassl

University of Western Australia | UWA · ARC Centre of Excellence in Plant Energy Biology

The societies of ants, bees and wasps are genetically closed systems where queens only mate during a brief mating episode prior to their eusocial life and males therefore provide queens with a lifetime supply of high-quality sperm. These ejaculates also contain a number of defence proteins that have been detected in the seminal fluid but their func...

Honey bee ( Apis mellifera ) males are highly susceptible to infections with the fungal pathogen Nosema apis . However, they are able to suppress this parasite in the seminal fluid using immune molecules. We predicted that infected males would respond to infections by altering the seminal fluid proteome in order to minimize the risk to sexually tra...

Honey bees (Apis mellifera) host a wide range of parasites, some being known contributors towards dramatic colony losses as reported over recent years. To counter parasitic threats, honey bees possess effective immune systems. Because immune responses are predicted to cause substantial physiological costs for infected individuals, they are expected...

Honey bee nutritional health depends on nectar and pollen, which provide the main source of carbohydrates, proteins and lipids to individual bees. During malnutrition, insect metabolism accesses fat body reserves. However, this process in bees and its repercussions at the colony level are poorly understood. Using untargeted lipidomics and gene expr...

Honey bees provide essential environmental services, pollinating both agricultural and natural ecosystems that are crucial for human health. However, these pollination services are under threat by outbreaks of the bacterial honey bee disease American foulbrood (AFB). Caused by the bacterium, Paenibacillus larvae, AFB kills honey bee larvae, convert...

Honey bees can host a remarkably large number of different parasites and pathogens, and some are known drivers of recent declines in wild and managed bee populations. Here, we studied the interactions between the fungal pathogen Nosema apis and seminal fluid of the Western honey bee (Apis mellifera). Honey bee seminal fluid contains multiple antimi...

Poster presented at the 46th Apimondia International Apicultural Congress, Montreal Sept 8-12 2019

All social insects with obligate reproductive division of labour evolved from strictly monogamous ancestors, but multiple queen-mating (polyandry) arose de novo in several evolutionarily derived lineages. Polyandrous ant queens are inseminated soon after hatching and store sperm mixtures for a potential reproductive life of decades. However, they c...

Declines in native insect pollinator populations and substantial losses in managed honey bees have been reported on a global scale and become a widespread concern because of the importance of these insects for human food production and ecosystem stability. Several potential factors have been studied as possible causes of declining pollinator health...

A poster of my PhD project that I presented at the 2018 European Congress of Apidology (EurBee) in Ghent, Belgium

Significance Management of oxidative stress in plant chloroplasts involves signaling pathways to the nucleus that trigger stress response mechanisms. Yet, how oxidative stress is initially sensed in the chloroplast to activate accumulation of a stress signal remains enigmatic. We show that inactivation of a phosphatase, SAL1, by oxidative stress in...

Glutaredoxins (Grxs) are small proteins that function as oxidoreductases with roles in deglutathionylation of proteins, reduction of antioxidants and assembly of iron-sulphur (Fe-S) cluster-containing enzymes. Which of the 33 Grxs in Arabidopsis perform roles in Fe-S assembly in mitochondria is unknown. We have examined in detail the function of th...

An individually darkened leaf model was used to study protein changes in the Arabidopsis mutant stay-green1 (sgr1) to partially mimic the process of leaf covering senescence that occurs naturally in the shaded rosettes of Arabidopsis plants. Utilizing this controlled and predictable induced senescence model has allowed the direct comparison of sgr1...

Cyclotides are a large family of plant peptides that are structurally defined by their cyclic backbone and a trifecta of disulfide bonds, collectively known as the cyclic cystine knot (CCK) motif. Structurally similar cyclotides have been isolated from plants within the Rubiaceae, Violaceae, and Fabaceae families and share the CCK motif with trypsi...

ABSTRACT: Matrix-Assisted Laser Desorption/Ionisation (MALDI) mass spectrometry imaging (MSI) uses the power of high mass resolution time of flight (ToF) mass spectrometry coupled to the raster of lasers shots across the cut surface of tissues to provide new insights into the spatial distribution of biomolecules within biological tissues. The histo...

Supplementary Protocol: A Beginner's Guide to MALDI-MS Imaging of Proteins in Plant Tissue. A step-by-step experimental protocol for MALDI-MS imaging of plant tissue. The protocol starts with tissue collection, preparation and storage; covers section preparation for MALDI-imaging and analysis and concludes with data processing. The protocol further...

Meiosis is the cell division that generates haploid gametes from diploid precursors. To provide insight into the functional proteome of budding yeast during meiosis, a 2-D DIGE kinetic approach was used to study proteins in the pH 6-11 range. Nearly 600 protein spots were visualised and 79 spots exhibited statistically significant changes in abunda...

Meiosis, the developmental programme generating haploid gametes from diploid precursors, requires two cell divisions and many innovations. In budding yeast, a large number of genes are expressed exclusively during meiosis while others are repressed compared to vegetative growth. Microarray analysis has shown that gene expression during meiosis is h...

Psychiatric disorders such as Alzheimer's disease, schizophrenia and mood disorders are severe and disabling conditions of largely unknown origin and poorly understood pathophysiology. An accurate diagnosis and treatment of these disorders is often complicated by their aetiological and clinical heterogeneity. In recent years proteomic technologies...

Sample degradation is a common problem in all types of proteomic analyses as it generates protein and peptide fragments that can interfere with analytical results. An important step in preventing such artefacts is to preserve the native, intact proteome as early as possible during sample preparation prior to proteomic analysis. Using the budding ye...

The pathophysiology of autistic spectrum disorder (ASD) is not fully understood and there are no diagnostic or predictive biomarkers. Proteomic profiling has been used in the past for biomarker research in several non-psychiatric and psychiatric disorders and could provide new insights, potentially presenting a useful tool for generating such bioma...

Over the last decade, genomics research in psychiatry and neuroscience has provided important insights into genes expressed under different physiological and pathophysiological conditions. Contrary to the great expectations regarding a clinical use of these datasets, genomics failed to improve markedly the diagnostic and therapeutic options in brai...

Durch die Genforschung („Genomics”) konnten in den letzten Jahrzehnten wichtige Erkenntnisse zu grundlegenden physiologischen und pathophysiologischen Prozessen gewonnen werden, die für die Psychiatrie relevant sind. Dadurch entstanden auch Hoffnungen für baldige klinische Anwendungsmöglichkeiten. Leider konnte die Genforschung jedoch bisher diesen...