Periodic Reporting for period 1 - MEL-ROD (MELANOPSIN CONTRIBUTION TO PATTERNS DISCIRMINATION IN DIURNAL AND NOCTURNAL RODENTS)
Reporting period: 2020-09-02 to 2022-09-01
The main goal of the project ‘Melanopsin contribution to patterns discrimination in diurnal and nocturnal rodents’ (MEL-ROD) was to compare different aspects of visual and circadian systems between nocturnal and diurnal animals with the emphasis put on melanopsin contribution to their functioning. Most of our knowledge about image and non-image forming vision comes from studies performed on mice and rats, which are nocturnal animals and its direct translation to humans is difficult, if not impossible. Thus, to better understand how vision and circadian clock work, we decided to use a diurnal murid rodent closely related to mouse called Rhabdomys pumilio or four-stripped African mouse. By using R. pumilio as an experimental animal we were aiming to fill the gap in our understanding of day-time vision and mechanisms behind day-night changes in neuronal activity. It is an important project for a society as it provides a more complete view on the visual and circadian systems across different ecological types of rodents and enables more straightforward comparison with humane vision.
The specific scientific objectives of the MEL-ROD project were: 1) to compare the characteristic of the ‘melanopic image’ between nocturnal, diurnal and melanopsin knockout animals, 2) to compare different aspects of vison such as colour, contrast, etc. between nocturnal mouse and diurnal R. pumilio but also to answer the question how does diurnality influence the way the biological clock responds to different visual stimuli and 3) to develop a method allowing simultaneous neuronal brain activity recordings and 3D tracking of freely moving animals performing different visual tasks. Additionally, MEL-ROD aimed at providing sufficient training activities that will enable MSCA Fellow to develop technical, scientific, and transferable skills in order to become an independent scientist.
The specific scientific objectives of the MEL-ROD project were: 1) to compare the characteristic of the ‘melanopic image’ between nocturnal, diurnal and melanopsin knockout animals, 2) to compare different aspects of vison such as colour, contrast, etc. between nocturnal mouse and diurnal R. pumilio but also to answer the question how does diurnality influence the way the biological clock responds to different visual stimuli and 3) to develop a method allowing simultaneous neuronal brain activity recordings and 3D tracking of freely moving animals performing different visual tasks. Additionally, MEL-ROD aimed at providing sufficient training activities that will enable MSCA Fellow to develop technical, scientific, and transferable skills in order to become an independent scientist.
Work performed during this fellowship was broadly divided into six work packages, where packages 1-4 where strictly connected to the scientific question asked and thus animal and laboratory work, whereas work packages 5-6 were ascribed to project management and dissemination. The MSCA Research Fellow worked at the University of Manchester under the supervision of Professor Rob Lucas between 2nd September 2020 and 1st September 2022. Experiments performed during WP1 has shown that melanopsin contributes to visual responses, enhances contrast sensitivity and contributes to spatio-temporal frequency tuning at the level of neuronal activity in the dorsal lateral geniculate nucleus (dLGN, part of the visual thalamus). These results confirm melanopsin role in image-forming vision. Results acquired during WP2 and WP3 show that regardless of the temporal niche, neurons within the biological clock (hypothalamic suprachiasmatic nucleus, SCN) not only respond to light stimuli in a similar way but also sufficiently well code irradiance in their maintained firing rate even when more naturalistic stimuli are co-applied. On the other hand, the high percentage and sensory diversity of light-responsive neurons outside the SCN in R. pumilio suggest widespread processing of more sophisticated visual information in the peri-SCN region suggesting enlargement of the visual hypothalamus in this diurnal rodent. Work performed during WP4 resulted in developing a method allowing simultaneous neuronal brain activity recordings and 3D tracking of freely moving animals. The main results showed a widespread coupling between neuronal activity in the visual thalamus and select behavioural parameters. In particular, postures associated with the animal looking up (“look up” neurons) or when the animal was looking down (“look-down” neurons). Developed method can be applied to various behavioural experiments where animal perform specific tasks or are freely moving. WP5 was devoted to project management and MSCA Fellow training activities which were mostly focus on improving her laboratory and analytical skills and research productivity, as well as learning new tools, methods, and techniques. All of it was implemented and successfully achieved. In WP6, the Fellow has participated in eight scientific conferences and meetings in the UK and outside as an active participant so giving talks and presenting scientific posters showing MEL-ROD project results. She has also delivered ten public engagement activities spanning from meetings with high school pupils, to talk about carrier in science, to being active in social media and post about MEL-ROD results and updates.
Datasets acquired by implementing WP1-WP4 are reported in 1) two scientific papers published in high impact factor journals (Current Biology and Scientific Reports), 2) three upcoming manuscripts which are under development, 3) four talks and 4) four scientific posters presented during conferences in and outside the UK. The Fellow was awarded the best poster award twice for the result acquired during implementation of MEL-ROD project.
Datasets acquired by implementing WP1-WP4 are reported in 1) two scientific papers published in high impact factor journals (Current Biology and Scientific Reports), 2) three upcoming manuscripts which are under development, 3) four talks and 4) four scientific posters presented during conferences in and outside the UK. The Fellow was awarded the best poster award twice for the result acquired during implementation of MEL-ROD project.
MEL-ROD project has generated new and exciting knowledge about the visual and circadian systems of nocturnal and diurnal animals. It is a comprehensive comparative study investigating differences and similarities between light-responsive neurons in the visual thalamus and hypothalamus in nocturnal mice and diurnal Rhabdomys pumilio. Introduction of this new laboratory rodent has taken the project to the next level of our understanding of visual and circadian systems and has made a direct translation to humans more straightforward. Moreover, MEL-ROD project has used a bunch of new technologies, such as CRISPER-Cas9 genetic manipulations, genetically modified animals, chronic electrophysiological experiments combined with 3D video tracking, silent substitution method of light stimuli design, to best test its hypothesis and achieve planned goals. Recently published manuscript in Current Biology (26th Sep 2022) has already gained a lot of attention and was commented in. The Fellow was awarded twice the best poster award for the acquired results what confirms big interest in the project and its potential for further high impact factor publications. All of it confirms that project implementation was performed well. It has opened a new direction for not only animal’s and human’s research but also visual engineering and industry. Project results have potential to be used by clinicians to better understand mechanisms behind day- and night-time vison and lightening industry and visual engineering to better design day-time lightening which is very important for humans’ best performance at schools and work places. With no doubt MEL-ROD project has taken the career of the Fellow at the stage of independent scientist by enriching her experience as a neurobiologist, improving her research productivity and extensively broaden her scientific and analytical knowledge.