People
Prof. Gerben van Ooijen
Chair in Chronobiology
Director of BBSRC EASTBIO DTP
Mental Health First Aider
After receiving a PhD for his work at the Molecular Plant Pathology group at the University of Amsterdam in 2008, Gerben joined Andrew Millar's lab at the Centre for Systems Biology at Edinburgh, where he contributed to the discovery of purely non-transcriptional circadian rhythms across eukaryotes. He then secured a University Research Fellowship from the Royal Society, London, to continue to study cellular timekeeping. Gerben's lab employ the model plant Arabidopsis and the unicellular alga Ostreococcus tauri. The latter is used as a starting point for comparative biology of clocks across all eukaryotes, in various collaborations.
Outside the lab, Gerben is a keen home brewer, plays the drums, enjoys running and spending time with his family.
Tel.: 0131 6 513 314 or Gerben.vanOoijen@ed.ac.uk
Dr. Uma Jayachandran (post-doc)
Uma joined as a post-doctoral researcher in the van Ooijen lab in 2023. She is elucidating the role of magnesium transport proteins in the picoplankton, Ostreococcus tauri and studying how they exert their control over the magnesium ion rhythms and thus effect the circadian clock.
In her free time, she likes to read, walk/hike and spend time with her family.
Dr. Ana Belen Romero-Losada (post-doc)
Ana Belén joined the van Ooijen lab as a postdoc in 2024. She completed her PhD in the Systems Biology and Biotechnology lab at the University of Seville, where she get the opportunity to work with different photosynthetic organisms and gain lots of experience in bioinformatics. However, she fell in love with rhythms and small eukaryotes, leading to her thesis titled "Multi-omics Characterization of the Responses to Seasonal Variations in Diel Cycles in the Marine. She has significantly contributed to the understanding of circadian and seasonal rhythms in eukaryotes and, in her new position in this lab, she plans to continue elucidating how rhythms work.
Outside the lab, Ana Belén enjoys exploring various artsy skills, from pottery and embroidery to different illustration methods. She always has a never-ending list of creative projects in progress.
Dr. Natalie Rogers (post-doc)
Natalie joined the van Ooijen lab as a postdoctoral researcher in 2025. At the University of Manchester, Natalie completed an MSci in Neuroscience and a PhD in circadian biology. During the PhD she investigated osmotic stress as a potential zeitgeber for cellular clocks and examined the effects of ablating Bmal1-mediated transcriptional rhythms in intervertebral disc cells. This work fostered her interest in the emerging and critical role of ion channels in regulating circadian rhythms. In the van Ooijen lab, Natalie will explore the role of circadian rhythms in potassium and magnesium in regulating key cellular processes such as glycolysis.
Outside of the lab, Natalie enjoys running, drawing, drinking coffee and chatting!
Irene Aldazabal (PhD student)
Irene is an interdisciplinary artist pursuing her PhD in Art at the University of Edinburgh. Her artistic methodologies involve botanical illustration, experimentation with organic materialities, and the creation of sculptures co-composed with plants and fungi. These practices have gradually expanded Irene’s attentiveness towards earthly living rhythms, bringing her work close to chronobiology. In association with the van Ooijen Lab, her doctoral research focuses on plants’ rhythmicity and circadian patterns to reimagine multispecies coexistence and wellbeing through art, considering the ecological dimensions of time.
Irene enjoys being outdoors, sharing with friends and family, and attending cultural events.
Do visit Irene's website and ECA profile!
Selen Dinge (PhD student)
In 2023, Selen completed her BSc in Molecular Biology and Genetics at Baskent University in Turkey and her MSc in Biotechnology in 2024 at the University of Glasgow. Her MSc project, conducted in Dr. Matt Jones's lab, focused on the circadian clock and temperature response. Outside of the lab, I enjoy playing piano, hiking, and dancing.
Selen worked as a Research assistant in the GvO lab for a year and will be starting her PhD in October 2025, funded by the Darwin Trust of Edinburgh.
Hanhan Zhang (PhD student)
Hanhan joined the van Ooijen lab in 2025 as a BBSRC EASTBIO-funded PhD candidate. She previously spent seven years at Beijing Normal University, where she earned both her B.Sc. and M.Sc. while specializing in calcium signalling. There she created a suite of genetically encoded Ca²⁺ indicators that illuminate sub-cellular calcium dynamics with high spatiotemporal precision. In Edinburgh she is extending this expertise to build fluorescent sensors for potassium and magnesium. Out of the lab, Hanhan is a big fan of musicals and detective novels. And she also enjoys traveling with her families and friends.
Dr. Yen Peng (Apple) Chew (post-doc)
Apple is a postdoctoral research associate with the van Ooijen lab focusing on improving CRISPR Cas9 editing efficiencies in microalgae Ostreococcus tauri. ORCiD and LinkedIn.
Outside of the lab, Apple enjoys dancing, crocheting and hiking.
PAST MEMBERS
Roman Barraud
Roman did his summer internship with the GvO lab in summer 2025, gratefully funded by iCM summer studentship. Roman investigated the use of two new antibiotic selection markers for Ostreococcus tauri.
Lukas Bengtsson
Lukas was a BSc Hons degree in Biochemistry in our lab. As part of his final year honours project, he joined the van Ooijen lab, where he worked under Uma’s supervision.
Katie Riccio
Katie did her bioinformatics Honours project with Dr Ana Belen and created a webtool called PROTAUR for the van Ooijen lab.
Dr. Olivia Fraser
Olivia completed her BSc in Biology at the University of Edinburgh, where her interest in plant biology first began and developed. Her fascination of plants was confirmed after her summer internship with the Halliday Lab in 2019 and continued by completing her honours project in the McCormick Lab. In her PhD, she was investigating the intricacies of the plant circadian clock and its interaction with the immune system. Olivia began her PhD research in 2020 and was funded by the BBSRC EASTBIO studentship.
Sami Luka Marcelino Benzaza
Sami was a BSc Hons degree in Biochemistry in our lab. As part of his final year honours project, he joined the van Ooijen lab, where he worked under Uma’s supervision.
Dr. Holly Kay
Holly completed her PhD in 2022 focusing on circadian biology using Ostreococcus tauri. Her thesis was titled Post-transcriptional regulation of the proteome in Ostreococcus tauri. She was funded by the Royal Society.
Dr. Sergio Gil
Sergio explored circadian rhythms in other eukaryotic organisms with the van Ooijen lab as a post-doc. Sergio found new and efficient methods to monitor circadian magnesium rhythms in vivo in the microalga Ostreococcus tauri. Sergio was funded by the Wellcome Trust.
Haomiao (Hermi) Cheng
Haomiao spent her early years in China before moving to Edinburgh to meet a different world. She started her PhD in 2021 and is funded by the Darwin Trust of Edinburgh. She is a microalgae enthusiast, and studied Chlorella physiology and diatom genetics during her undergraduate and masters research.
Dr. Helen Feord
Helen was funded by a BBSRC EASTBIO studentship, and worked on magnesium transport in Ostreococcus. She has graduated with a PhD with thesis titled: Circadian magnesium transport in eukaryotic cells. She started a postdoc job in the Benning lab in Potsdam, working on algae-dominated microbial communities in glacial environments in Greenland. Glaciers! Greenland!
Dr. Samantha Cargill
Samantha completed her PhD in 2021, following a first year at the Scottish Rural College and 2.5 years in our lab. Her thesis was named Crosstalk between the plant circadian clock and immunity, and Sam is currently re-training to be a financial adviser.
Babette Vlieger - Babatte joined us on an 8-month Erasmus+ studentship in 2019/2020. She worked with Holly on characterising the effects of methylation inhibition on the clock in Ostreococcus, and lend a helping hand on long proteomics timeseries. She is currently a PhD student at the Molecular Plant Pathology group of the University of Amsterdam.
Ellen Grünewald - Ellen joined the lab as a postdoc to identify regulators of cellular circadian timekeeping using proteomics approaches. Her experience with mammalian cell biology helped her to develop very useful research tools for Ostreococcus. Ellen now has her own highly successful Medical Writing company, Articulife.
Ísarr Nikulás Gunnarsson - Ísarr joined the lab for his Biotechnology Honours project in 2019. Supervised by Helen, he investigated proteins involved in circadian magnesium rhythms in Ostreococcus.
Dr. Louise Hansen - Louise came to our lab as our first PhD student in 2013, and after that stayed on as a post-doc. Louise was very successful in our lab and was involved in setting up many of the methodologies we employ. As a PhD student Louise identified a role for SUMOylation in the circadian system of Arabidopsis, resulting in her three first-author papers. As a post-doc she worked on cellular rhythms in Ostreococcus, generating a number of leads for new projects and contributing to the 2016 paper on magnesium rhythms. Louise is now back in her home town of Copenhagen, working for the pharmaceutical company Novo Nordisk.
Annabel Summerfield - Annabel joined our lab on a Sainsbury Undergraduate Studentship, funded by the Gatsby foundation in 2017. She made excellent progress on identifying a link between circadian potassium rhythms and plant growth. After finishing up her degree in plant biology at Bristol, she was accepted onto the Civil Service Fast Stream Programme.
Freddie Dear - Freddie joined our lab for his Biochemistry Honours project. He was working on the role of transmembrane ion transporters in the Ostreococcus clock. He is very talented on a skittles alley. After his degree Freddie joined the Wellcome Trust trainee scheme and is now a partner in the Trust's scientific investment management company, Syncona.
Sjoerd Smit - Sjoerd joined our lab on an Erasmus studentship, studying SUMOylation in the plant circadian clock in 2015. His brewing made a lasting impression. After finishing his degree, Sjoerd started a traineeship for young academics combining government and industrial placements with gaining teaching accreditation. He is also teaching biology in a college for adult students.
