New DNA modification ‘signature’ discovered in zebrafish — ScienceDaily

Researchers at the Garvan Institute of Medical Research have uncovered a new form of DNA modification in the genome of zebrafish, a vertebrate animal that shares an evolutionary ancestor with humans ~400 million years ago.

Dr Ozren Bogdanovic and his team discovered that unusually high levels of DNA repeats of the sequence ‘TGCT’ in the zebrafish genome undergo a modification called methylation, which may change the shape or activity of the surrounding DNA. The study, published in Nucleic Acids Research and conducted in collaboration with Queen Mary University of London, could lead to the development of new experimental models for studying how DNA modifications impact human development and disease.

“We’ve revealed a new form of DNA methylation in zebrafish at TGCT repeats, and crucially, the enzyme that makes the modification,” says Dr Bogdanovic, who heads the Developmental Epigenomics Lab at Garvan and Senior Research Fellow at the School of Biotechnology

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Learning how a zebrafish moves will aid understanding of human movement and disorders — ScienceDaily

Movement in animals is complex, especially in human beings. A variety of neurons coordinate the activity and inactivity of our muscles, and without that coordination we’d fall flat on our face when we went for a walk.

Scientists have known for quite some time how motor neurons in the spinal cord that activate muscles are organized to generate more forceful output, to transition from walking to jogging to running, for example. Little is known, however, about how spinal inhibitory interneurons work to inhibit, or silence, other neurons and related muscle groups in coordination with the active muscle groups across changing speeds.

Now a Northwestern University research team has discovered in a study of zebrafish that there is a very orderly relationship between when these critical inhibitory neurons are born, their participation in different speeds of movement and what part of a motor neuron they innervate. As a result of this

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