RAPID IDENTIFICATION AND ISOLATION OF ZEBRAFISH CDNA CLONES

A fast and economical approach, referred to as cDNA clone tagging, was adapted to identify and isolate zebrafish cDNA clones. The basic appr oach was to partially sequence the coding region of size selected cDNA clones and the partial sequences were then used as tags for identifyi ng the clones through homology search. To benefit maximally from the t agging approach, two cDNA libraries, derived from embryonic and adult fish poly(A)(+) RNAs, respectively, were constructed by unidirectional cloning; conceptually, they have the potential to represent all expre ssed zebrafish genes. A total of 1084 clones were sequenced from the t wo libraries, and 511 clones were identified, based on sequence homolo gy. These identified clones were derived from at least 261 genes, enco ding 48 translational machinery proteins, 47 cytosolic proteins, 43 cy toskeletal proteins, 41 nuclear proteins, 32 membrane proteins, 22 sec reted proteins, 20 mitochondrial proteins and 8 proteins with an unkno wn location. Of the 261 distinct cDNA clones identified, 254 were isol ated for the first time in the zebrafish. These tagged cDNA clones, id entified and unidentified, provide rich resources for developmental an alysis as well as mapping of zebrafish genome. The long-term objective of this study is to establish a tagged zebrafish gene library that ca n be accessed both by hybridization screening against the plasmid DNAs and by electronic screening using the sequence information. (C) 1997 Elsevier Science B.V.