DSCAM (Down syndrome adhesion molecule); structure and function in a crustacean.
2012 (English)Conference paper, Presentation (Other academic)
In invertebrates, the circulating blood cells (hemocytes) are crucial for protecting the animal against invading microorganisms, and they are directly involved in recognition, phagocytosis, melanization and cytotoxic reactions. Many microorganisms trigger hemocyte synthesis and release from the HPT, and this may be one way for the host to respond to an infection. Therefore we have studied hematopoiesis intensely and have now in detail deciphered the molecular mechanisms in hematopoietic stem cell proliferation and differentiation. Recently we have cloned Dscam proteins from P. leniusculus. The Down syndrome cell adhesion molecule (Dscam) is a member of the immunoglobulin super family of proteins. In vertebrates Dscam was first identified for its importance in developing neural tissue, and for its critical role in Down Syndrome.These cell adhesion molecules are large proteins containing ten Ig domains and six fibronectin type III domains, and this structure is conserved across animal phyla. There are two Dscam genes in humans (DSCAM), and there are evidences for a conserved essential role in neural wiring, in both vertebrate and insects. An intriguing difference in Dscam gene structure is the exon duplication that have occurred in arthropods and which give rise to an array of alternative spliced isoforms in insects and crustaceans. Alternative splicing of individual exon sequences occurs in a mutually exclusive manner and allows for expression of several thousands of isoforms.
We have now shown that hemocytes that express different spliced isoforms are induced by specific challenge, and moreover that these specific forms are important in clearing bacteria. This differential splicing may be one new area of research that may help to explain how crustaceans and insects as effectively can manage to distinguish between harmless and harmful microorganisms.
Place, publisher, year, edition, pages
IdentifiersURN: urn:nbn:se:uu:diva-189808OAI: oai:DiVA.org:uu-189808DiVA: diva2:582331
The 12th Congress of the International Society of Developmental and Comparative Immunology,Hilton Fukuoka Sea Hawk Hotel, Fukuoka city, Japan,9th to 13th July, 2012.