Sequencing of EST libraries from the European eel (Anguilla anguilla)

Summary, The evolutionary success of aquatic organisms in many diverse freshwater (FW) and sea water (SW) habitats has been made possible by the development of complex inter-related ion and water transport systems which allow them to osmoregulate and survive in extreme hypotonic and hypertonic environments. Well-studied examples of this are the euryhaline teleosts, such as the European eel, which exhibit the genetic plasticity to enable survival in both FW and SW environments with only minimal changes in the osmolality and ionic composition of their body fluids. The European eel has proved to be an excellent model species for the study of osmoregulation in euryhaline teleosts and recently, work funded by the NERC has enabled the production of EST libraries from the gill, intestine, kidney, gonad and brain which together comprise over 12,000 tissue-specific clones. This eel clone set has been used to produce two separate 18,000 feature microarrays which are produced and currently available for use by the Liverpool Microarray Facility, School of Biological Sciences, The University of Liverpool. However, only less than 1200 of the clones which serve as features on the arrays have been sequenced. This application requests support for the sequencing of the remaining clones and the general housekeeping of the libraries which will involve re-plating all clones to reduce redundancy to below 5%. The re-formulated library will be fully annotated and ESTs characterised in terms of sequence homologies with other teleost genomes (zebrafish, fugu) and to genes deposited within other gene banks. The sequence information will not only be useful for array feature annotation but will also have wide-ranging implications for many research groups working on different aspects of teleost osmoregulation and toxicology as well as the many groups investigating the population genetics and dynamics of various eel sub-species.