The co-expression of visual pigments in a single photoreceptor: environmental regulation and spectral tuning. The light sensitive cells (photoreceptors) in the vertebrate retina contain filters (oil droplets) and visual pigments (opsins). These structures tune the incoming light and initiate the visual process, respectively. Exciting new research reveals that some vertebrates express more than one opsin within a single photoreceptor. We plan to examine the regulation of single and two co-express ....The co-expression of visual pigments in a single photoreceptor: environmental regulation and spectral tuning. The light sensitive cells (photoreceptors) in the vertebrate retina contain filters (oil droplets) and visual pigments (opsins). These structures tune the incoming light and initiate the visual process, respectively. Exciting new research reveals that some vertebrates express more than one opsin within a single photoreceptor. We plan to examine the regulation of single and two co-expressed opsin genes by manipulating the light environment. We expect to determine the environmental triggers for visual pigment tuning and the effects of co-expression on colour vision.Read moreRead less
Environmental regulation of opsin expression and spectral tuning in the vertebrate retina. Exciting new evidence shows that the vertebrate visual system is extraordinarily plastic and that the colour and brightness of the ambient light regulates both the spatial and temporal expression of visual pigments (opsin) genes and the degree of spectral filtering in the retina. Based on findings that more than one visual pigment can be co-expressed in a single photoreceptor type, we plan to manipulate th ....Environmental regulation of opsin expression and spectral tuning in the vertebrate retina. Exciting new evidence shows that the vertebrate visual system is extraordinarily plastic and that the colour and brightness of the ambient light regulates both the spatial and temporal expression of visual pigments (opsin) genes and the degree of spectral filtering in the retina. Based on findings that more than one visual pigment can be co-expressed in a single photoreceptor type, we plan to manipulate the light environment in order to identify and quantify the effect of different lighting regimes by morphological, spectral and molecular techniques in a concerted effort to understand the regulation of opsin expression.Read moreRead less
The evolution of colour vision in vertebrates. Colour vision plays a crucial role in the lives of many animals including vertebrates. However, very little is known about the origins of colour vision and we aim to fill this gap. Photoreceptors (cone cells) with sensitivities to different colours mediate colour vision (humans possess blue, green and red cones). This study will examine the structure, physiological responses and molecular biology of these cells in the closest living relatives of the ....The evolution of colour vision in vertebrates. Colour vision plays a crucial role in the lives of many animals including vertebrates. However, very little is known about the origins of colour vision and we aim to fill this gap. Photoreceptors (cone cells) with sensitivities to different colours mediate colour vision (humans possess blue, green and red cones). This study will examine the structure, physiological responses and molecular biology of these cells in the closest living relatives of the early vertebrates. The underlying mechanisms for spectral tuning, the genetic rate of evolutionary change and the importance of colour in visual ecology will also be examined.Read moreRead less
The development and evolution of the pelvic girdle in basal gnathostomes. Comparing the development of muscles, cartilage and bone in representatives of all three major groups of fish will provide information as to how structures evolved but also how the adult morphology is distributed in phylogeny. Because so little is known about the genetic mechanisms underlying the formation of the pelvic girdle in fish, it is important to start studying a model animal such as the zebrafish. The pathways unc ....The development and evolution of the pelvic girdle in basal gnathostomes. Comparing the development of muscles, cartilage and bone in representatives of all three major groups of fish will provide information as to how structures evolved but also how the adult morphology is distributed in phylogeny. Because so little is known about the genetic mechanisms underlying the formation of the pelvic girdle in fish, it is important to start studying a model animal such as the zebrafish. The pathways uncovered have the potential to describe mechanisms common to all jawed vertebrates, not only common to fish. Understanding the mechanisms that generate major morphological transition in the vertebrate lineage necessarily informs us about our own evolutionRead moreRead less
Specification and evolution of vertebrate appendicular muscle. Previously we have determined that two different developmental mechanisms are utilised to make the muscles present within the fins and limbs of distinct vertebrate species. This proposal is concerned with determining the morphogenetic, evolutionary and molecular basis for these two different developmental modes. To do this we will to extend our observations more widely to examine muscle formation in both the paired fins in a phyloge ....Specification and evolution of vertebrate appendicular muscle. Previously we have determined that two different developmental mechanisms are utilised to make the muscles present within the fins and limbs of distinct vertebrate species. This proposal is concerned with determining the morphogenetic, evolutionary and molecular basis for these two different developmental modes. To do this we will to extend our observations more widely to examine muscle formation in both the paired fins in a phylogenetically diverse context. We further hope to determine the underlying genetic basis for these different morphologies by developing techniques to examine their formation in a number of embryonic contexts.Read moreRead less