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Current Biology – Chitin in cartilaginous fishes

Our new work in collaboration with Chris Amemiya’s lab at UC Merced demonstrates the presence of Chitin in an unexpected place – the electro sensory organs of cartilaginous fishes.

Molly Phillips, W. Joyce Tang, Matthew Robinson, Daniel Ocampo Daza, Khan Hassan, Valerie Leppert, Linda S. Hirst, Chris T. Amemiya,
“Evidence of chitin in the ampullae of Lorenzini of chondrichthyan fishes”, Current Biology, Volume 30, Issue 20, 2020, Pages R1254-R1255,
https://doi.org/10.1016/j.cub.2020.08.014.

Read a news article here

https://news.ucmerced.edu/news/2020/hard-shells-and-electrosensory-gels-lab-makes-surprising-discovery

Abstract,We previously reported that the polysaccharide chitin, a key component of arthropod exoskeletons and fungal cell walls, is endogenously produced by fishes and amphibians in spite of the widely held view that it was not synthesized by vertebrates [1]. Genes encoding chitin synthase enzymes were found in the genomes of a number of fishes and amphibians and shown to be correspondingly expressed at the sites where chitin was localized [1,2]. In this report, we present evidence suggesting that chitin is prevalent within the specialized electrosensory organs of cartilaginous fishes (Chondrichthyes). These organs, the Ampullae of Lorenzini (AoL), are widely distributed and comprise a series of gel-filled canals emanating from pores in the skin ( Figure 1A). The canals extend into bulbous structures called alveoli that contain sensory cells capable of detecting subtle changes in electric fields ( Figure 1B) [3,4]. The findings described here extend the number of vertebrate taxa where endogenous chitin production has been detected and raise questions regarding chitin’s potential function in chondrichthyan fishes and other aquatic vertebrates.

Fundamentals of soft matter science

Professor Hirst is the author of “Fundamentals of soft matter science” (Taylor and Francis, CRC Press) 2012

About the book

Soft materials such as liquid crystals, polymers, biomaterials, and colloidal systems touch every aspect of our lives. Not 9781439827758surprisingly, the rapid growth of these fields over the past few decades has resulted in an explosion of soft matter research groups worldwide. Fundamentals of Soft Matter Science introduces and explores the scientific study of soft matter and molecular self-assembly, covering the major classifications of materials, their structure and characteristics, and everyday applications.

Designed for beginners to the field with a basic scientific background, this readable book emphasizes conceptual understanding, minimizing detailed mathematical derivations. Each chapter is dedicated to a different group of soft materials, including liquid crystals, surfactants, polymers, colloids, and soft biomaterials. Each subject is broken down into the essential concepts: material structures and physical characteristics, some simple theoretical ideas, and important experimental methods. The book emphasizes commonly used experimental techniques and practical applications. Full color illustrations and photographs are incorporated throughout to help describe the systems and key concepts.

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