Picture  of Rachel McMullan

Dr Rachel McMullan

Senior Lecturer In Health Sciences

School of Life, Health & Chemical Sciences

rachel.mcmullan@open.ac.uk

Biography

Professional biography

I completed my PhD in Biosciences at The University of Birmingham in 2003, studying the role of Rho small GTPases in keratinocyte function. Following this I undertook a postdoc at the MRC Laboratory for Molecular Cell Biology investigating the function of Rho family small GTPases during neurotransmitter release in Caenorhabditis elegans.

In 2010 I became a Wellcome Trust Career Development Fellow at Imperial College using C. elegans to study the relationships between the nervous and immune systems the mediate responses to infection. 

I joined the School of Life, Health and Chemical Sciences in 2015 as a lecturer and am now a Senior Lecturer in Health Sciences. 

1999 BSc Biochemistry and Molecular Cell Biology The University of Birmingham 

2003 PhD Biosciences The University of Birmingham 

Research interests

Disgust and pathogen avoidance

The persistent threat posed by pathogens has driven the evolution of behavioural strategies that help free-living animals to reduce contact with infectious agents. These pathogen-avoidance behaviours are widespread across Animalia. In humans, the emotion that serves this function is disgust and strong associations between disgust elicitors and pathogen sources support the pathogen avoidance theory of disgust. 

The nematode Caenorhabditis elegans provides a powerful genetic model for understanding the biological basis of disgust-like behaviour. We and others have established C. elegans as system in which specific genes underlying pathogen avoidance behaviours can be identified and experimentally manipulated. This work opens the door to understanding the evolutionary role of disgust in host defence that may inform new approaches to conditions such as contamination-based OCD, specific phobias and other disgust-related pathologies.

Environmental Pollutants and Behaviour

My research examines how environmental pollutants—including agricultural chemicals and microplastics—affect behaviour, neural function and organismal health. Many of these pollutants occur at low but chronic levels in natural and occupational environments, yet their long‑term biological impact remains poorly characterised.

Using C. elegans as a tractable genetic and behavioural model, our work explores how different classes of pollutants influence avoidance behaviours, neural function and organismal health. This includes supervisory projects that investigate both chemical and particulate pollutants:

  • Neurotoxic Effects of Low‑level Organophosphate Exposure in C. elegans and UK Agricultural Workers (in collaboration with Dr Gini Harrison, Psychology) – examining how chronic, field‑relevant chemical exposures influence behavioural outcomes and neurobiological pathways relevant to stress and mood regulation.
  • A novel particulate‑avoidance behaviour and bacterial food availability reduce the risk of microplastic ingestion and retention in C. elegans (in collaboration with Dr Carl Boardman and Dr Simon Collinson) – characterising how nematodes detect and avoid microplastic particles, and how environmental context and food availability modify these avoidance strategies.

Tackling AMR through professional learning (Academic lead)

Understanding how healthcare professionals perceive, value and use antimicrobials, as well as the context in which they develop work practices related to AMR is central to research which centres on healthcare professionals involved in AMR-related activities and focuses on how they organise their work, how they adapt, change or develop new practices and how, through these processes, they may contribute to strengthening lab capacity, AMR stewardship and AMR surveillance systems to eventually reduce AMR.
In collaboration with the Fleming Fund the OU has designed flexible, contextually appropriate, technology-supported professional learning approaches that expand access to high  quality digital education on AMR surveillance for professionals working low resource settings. The OU has produced high  quality, interdisciplinary research on how technology - enhanced educational interventions can support learning across diverse healthcare related professional communities and geographies. A major outcome of this work is the Tackling AMR programme comprising a suite of freely accessible short online courses and an AMR practice toolkit hosted on OpenLearn Create, designed to strengthen AMR-related capabilities at scale. 

Teaching interests

Currently teaching on the following modules:

S291 Clinical laboratory diagnostics 

Previous teaching: 

S285 Investigative approaches in biology and chemistry 

SK298 Brain, mind and mental health 

SK320 Infectious disease and public health

S350 Evaluating contemporary science

 

Impact and engagement

I actively engage the public and wider stakeholder communities through a broad range of outreach, engagement and knowledge‑exchange activities. I have been a competitor in “I’m a Scientist, Get Me Out of Here” (2015) and have presented at major science festivals, including the 2018 Northern Ireland Science Festival (“Yuck, That’s Disgusting”) and the 2016 Cheltenham Science Festival (“The Disgust Instinct” with Valerie Curtis, LSHTM). I also run hands‑on primary‑school outreach activities such as “How clean are your hands?” and “Yuck, that’s disgusting” to help introduce children to microbiology, infection and health‑protective behaviours.

My engagement work also includes national‑level scientific communication. I contributed to RSC Science and the Assembly 2017, and in 2017 I organised the Royal Society meeting on the Evolution of Pathogen and Parasite Avoidance, which resulted in a themed issue of Philosophical Transactions of the Royal Society B in 2018.

Alongside public engagement, I contribute to institutional and societal impact through leadership roles. I have served as School Engagement and Enterprise Lead and as an Open Societal Challenges (OSC) Lead, supporting interdisciplinary work that translates research into societal benefit. I am currently the Impact Lead for REF UoA03, working to strengthen the visibility, quality and reach of impact arising from our research community.

 

 

Projects

Fleming Fund Grant Extension 2, to 31 Dec 2023

In October 2021 the Open University completed delivery of the second Global Learning Fleming Grant. It developed 25 online modules (OLCreate: Tackling antimicrobial resistance (open.edu)) and a toolkit (OLCreate: PUB_4849_1.0 Tackling antimicrobial resistance: the AMR surveillance toolkit (open.edu)). These are designed to promote greater understanding of AMR surveillance and the improvement and application of skills among AMR professionals, especially in Fleming Fund countries. The online modules and toolkit remain available on the Open University Open Learn platform beyond the end of the grant. Mott MacDonald and the Department of Health and Social Care asked OU to deliver this project's cost extention to provide monitoring data and associated analysis to monitor uptake of the modules and the toolkit. The data is to be disaggregated by module, pathway, AMR Toolkit and survey data. New contract Outputs: 1. Agree data reporting format with Mott MacDonald 2. Supply monitoring information and analysis throughout the contract period 3. Run quarterly data reports and carry out essential analysis as needed 4. Provide the data on a quarterly basis, by the 10th of the month following the end of the quarter. Simple table formats will suffice 5. Be prepared to have a brief phone call about the data each quarter in case of any queries 6. Take part in a review meeting in Q4 (Oct-Dec 2022) to discuss findings from the data and next steps

Fleming Fund Phase 2

Phase II of the Fleming Fund is further support to Fleming Fund countries to build-upon and advance the achievements of Phase I. Investing in similar areas, the programme focusses on four outcomes: 1. Production of quality AMR/U/C and burden data 2. Quality analyses of data 3. Sharing analyses and data with decision-makers 4. Promoting sustainable investment to counter AMR Phase II includes a programme of four grant streams: 1. Country Grants - To support implementation of quality assured national surveillance programmes for AMR/U/C and burden using a One Health approach and in line with Fleming Fund principles and National Action Plans; to provide coordination with other grant streams and with Government and other stakeholders; to work towards data and evidence use in policy and practice in human health, animal health and food production, food safety, and the environment; and to promote sustainability, primarily through resource mobilisation. 2. Fleming Fellowship Scheme Grants - To provide continual professional development and leadership opportunities for fellows to improve capabilities for production, analysis and use of data within the surveillance system. 3. Regional Grants – To provide technical assistance at a multi-country level to support and improve key technical functions for AMR surveillance systems in the production, analysis and use of data. 4. Strategic Alignment Grants – Grants that are used to take advantage of opportunities as they arise during the Phase II programme, under the principles of adaptive management.

Genetic analysis of post-developmental Rho GTPase signaling: identification and characterization of Rho signaling pathways required during the C. elegans immune response. (Transfer In)

Rho signaling has been extensively studied using biochemistry and cell-based assays that have demonstrated roles for Rho in many basic cell functions. These studies have told us a lot about the functions of Rho, however little about their importance in a whole animal. Rho signaling is essential during development making it difficult to study Rho’s role in adult animals. Analysis of adult Rho signaling pathways is important because aberrant signaling by these pathways has been implicated in human disease. In this study I aim to define the Rho pathways that act in adult animals. In particular I will identify those pathways that trigger changes in cell morphology as part of the C. elegans innate immune response. By identifying effectors important for this phenotype we will better understand Rho’s role in controlling cell morphology in adult animals. The innate immune system is evolutionarily conserved, for example, both Rho and MAPKinase function in the mammalian immune system and this is also true in C. elegans. In addition cross talk between Rho and MAPKinase pathways has been suggested to contribute to the action of oncogenic Ras. The molecular interactions that mediate this cross talk and Rho’s activation during the immune response remain poorly described and this phenotype provides a genetic model to dissect them. Defining these pathways and the relationships between them in C. elegans is likely to tell us more about how they are involved in innate immunity and misregulated in diseases such as cancer.

Publications

Digital Artefact

Tackling antimicrobial resistance programme: Fleming Fund online learning (2025)

Journal Article

Effectiveness of work-based educational interventions for antimicrobial stewardship: a systematic review (2024)

Addressing Global Challenges By Contextualising Learning At Scale: Future Professional Learning For The Health Sector (2024)

Addressing the persistent disconnect between learning and work: Using a Logic Model to support negotiations of diverse actors during the design of digital learning systems (2023)

The effect of the COVID-19 pandemic on disgust sensitivity in a sample of UK adults (2022)

Identification of a conserved, orphan G-protein coupled receptor required for efficient pathogen clearance in C. elegans (2019)

Activation of RHO-1 in cholinergic motor neurons competes with dopamine signalling to control locomotion (2018)

Evolution of pathogen and parasite avoidance behaviours (2018)

Neuronal and non-neuronal signals regulate Caernorhabditis elegans avoidance of contaminated food (2018)

From head to tail it's a 2 way street for neuro-immune communication (2014)

Serotonergic chemosensory neurons modify the C. elegans immune response by regulating G-protein signaling in epithelial cells (2013)

G-proteins: fighting infection on two fronts. (2012)

Behavioral and immune responses to infection require Gαq - RhoA signaling in C. elegans. (2012)

The Pseudomonas aeruginosa reference strain PA14 displays increased virulence due to a mutation in ladS. (2011)

The RHO-1 RhoGTPase modulates fertility and multiple behaviors in adult C. elegans. (2011)

Rho deep in thought. (2007)

The Gα12-RGS RhoGEF-RhoA signalling pathway regulates neurotransmitter release in C. elegans (2006)

Rho is a presynaptic activator of neurotransmitter release at pre-existing synapses in C. elegans. (2006)

Keratinocyte differentiation is regulated by the Rho and ROCK signaling pathway (2003)

Other

Work-based learning interventions for antimicrobial stewardship: a systematic review (2023)

Presentation / Conference

A putative C. elegans melatonin receptor is required for efficient pathogen clearance (2016)

Report

Tackling Antimicrobial Resistance through Professional Learning: The Development and Evaluation of the Global AMR Curriculum (2021)