CK EST Project
The goal of the CK library EST project aimed to characterize secreted and transmembrane proteins involved in intercellular communication during development. The project was conducted both at the BDGP and in the laboratory of Corey Goodman at U.C. Berkeley.
The CK library - named for its primary author Casey Kopczynski - consists of clones made from rough endoplasmic reticulum-bound mRNA, and is therefore enriched in clones encoding membrane and secreted proteins. To increase the representation of rare cDNAs in the library, the library was normalized using a novel method based on cDNA hybridization to genomic DNA-coated beads.
cDNAs were chosen for sequencing using a specialized screen that involves whole embryo in situ hybridization. A total of 2518 individual cDNAs from the normalized library were screened by in situ hybridization, and 917 of these cDNAs represent genes differentially expressed during embryonic development.
Sequence analysis of 1001 cDNAs revealed that 811 represent genes not previously described in Drosophila. Expression pattern photographs and partial DNA sequences have been assembled in a database and are publicly available from this web site. A total of 1691 CK ESTs have been submitted to dbEST.
The work of Kopczynski et al. is reported in PNAS 95(17):9973-8. You can read it [HERE].