Developmental regulation and primary structure of murine cellular nucleic acid‐binding protein, a zinc finger‐containing protein whose general structure is present in evolutionarily diverse eukaryotes

Abstract

Murine cellular nucleic acid binding protein (CNBP) cDNA was cloned during a differential screen of messages expressed in early postimplantation extraembryonic tissues. Sequence analysis indicates that CNBP belongs to a family of proteins that contains retroviral‐type zinc fingers (CCHC) and glycine‐rich domains and whose general structure is similar in Leishmania, the yeast Schizosaccharomyces pombe and in mammals. Transcripts representing four different CNBP proteins were detected during murine embryogenesis. Spatial analysis indicated that CNBP messages accumulated in a regulated pattern during postimplantation development. Most tissues expressed the CNBP message at E9.5 of embryonic development, with the exception of neural epithelia, developing gut and otic placode. By E12.5, the spatial pattern had become more restricted, but now included ependymal and mantal layers of the developing nervous system and differentiating lamina propria of the intestine. By E14.5, CNBP levels had decreased throughout all regions of the embryo. While the overall structure of CNBP‐like proteins is conserved in eukaryotes, the CNBP expression pattern is not consistent with a simple housekeeping role.