Screening from a subtracted embryonic chick hindbrain cDNA library: identification of genes expressed during hindbrain, midbrain and cranial neural crest development

The vertebrate hindbrain is segmented into a series of transient structures called rhombomeres. Despite knowing several factors that are responsible f or the segmentation and maintenance of the rhombomeres, there are still lar ge gaps in understanding the genetic pathways that govern their development . To find previously unknown genes that are expressed within the embryonic hindbrain, a subtracted chick hindbrain cDNA library has been made and 445 randomly picked clones from this library have been analysed using whole mou nt in situ hybridisation. Thirty-six of these clones (8%) display restricte d expression patterns within the hindbrain, midbrain or cranial neural cres t and of these, twenty-two are novel and eleven encode peptides that corres pond to or are highly related to proteins with previously uncharacterised r oles during early neural development. The large proportion of genes with re stricted expression patterns and previously unknown functions in the embryo nic brain identified during this screen provides insights into the differen t types of molecules that have spatially regulated expression patterns in c ranial neural tissue. Published by Elsevier Science Ireland Ltd.